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Japan is an island in the Pacific Ocean with dense cities, thousands of shrines and temples and mountainous national parks. With a population of 127 million and the currency of the Japanese yen, Japan has a fascinating and multi-faced culture. It is steeped in traditions dating back thousands of years, but it's society is in a constant state of flux. Their continually changing fashion and technological advancements are forever expanding the boundaries of what is possible.
Sport/recreation/movement plays a significant part in Modern day Japan. From a young age, many kids join school teams thus instilling a sense of pride, hard work and dedication which reflects the 'traditional values' of the Japanese culture. Japan is highly successful in baseball, badminton, football and tennis although is more renowned for their sports with an ancient profile in such things as: sumo, kendo, judo karate and aikido.

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Home to the world's largest urban metropolis, rugged wilderness, and a culture steeped in ancient tradition, Japan is a travelers dream.

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Japan has one of the best public transport systems in the world. Especially in the metropolitan areas and between larger cities. It is characterised by its punctuality, high quality service and the amount of general public use proving the worth of Japan's modern and highly efficient transport systems. It's noted for its outstanding low energy use compared to other countries, because of the high levels of rail transportation and overall travel distances. There are also 1.2km of paved roads which provide the main means of transport. Japan has left-hand traffic, single network high speed and limited access toll roads which are run by toll-collecting enterprises. Japan has also branched out into helping/investing in several countries' public transport systems e.g investing in the high speed D.C. to Baltimore train system. Japan's public transport system is most famous for "Shinkansen" more commonly known as the bullet train which are the high speed trains that run across the country. These trains run on 8 seperate lines from their commuting train counterparts.

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The traditional Japanese diet has a strong emphasis on vegetables, seafood, soy, clear broth, rice, green tea and seaweed. Their diet is typically semi-vegetarian with less fat, less sugar and more antioxidants than Australians. Because of their diet and healthy lifestyle, the Japanese people are amongst the thinest in the world. Naomi Moriyama composed an autobiography about her upbringing in Japan and how her health changed when she moved to America. In her book she noted that for the first time, she began to gain extra weight whilst living in America due to the western diet and lack of exercise.
Japanese women are masters of simple home cooking with high credentials. The traditional  home cooked meal is a piece of grilled fish with steamed rice and simmered vegetables, accompanied by a bowl of hot miso soup, to be finished off with sliced fresh fruit and a cup of hot green tea. In Japan, dietary guidelines recommend the consumption of at least 30 different foods daily in order to maintain good health.

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The traditional Japanese diet, with its emphasis on vegetables, seafood, soy, clear broth, rice, green tea and seaweed, is a semi-vegetarian diet with less fat, less sugar and more antioxidants than ours. It has none of the rich desserts, pastries and sweets of European cuisines. And it's paying dividends for the people who eat it.

In the midst of a global obesity epidemic, the Japanese have the lowest obesity rates in the developed world - 3 per cent compared to over 20 percent for Australians as well as lower rates of diabetes, high blood pressure, heart disease and some (but not all) cancers.

The elders of Okinawa

The Japanese are the world champions of longevity with an average life expectancy of 85 years for women and almost 80 for men. And Japan boasts the highest number of centenarians (people who live to be over 100) of any country.

Many of these centenarians live on Okinawa, one of a large group of islands south-west of Japan. More than any other population, older Okinawans are fit and agile, and their minds are clear and lucid. Few suffer the lifestyle-related diseases like heart disease, hormone-dependent cancer, diabetes and dementia that are so common in their western counterparts.

The women have a natural menopause and both sexes show strong bones well into their 80s and 90s.

While their genes confer some protection, it's the healthy diet and active lifestyle (martial arts, dancing, gardening, walking everywhere) that helps the Okinawans live to extreme ages, as born out by the landmark Okinawa Centenarian Study which ran for 25 years. This has become a New York Times bestseller The Okinawa Program.

Living lean

The Japanese diet also works to keep you slim. In her book Japanese Women Don't Get Fat or Old, Naomi Moriyama reveals the secrets of both the Japanese diet and its culture that keep Japanese so slim and youthful. Having grown up in Japan, it was not until she moved to the US to study that Naomi first put on weight and realised how her Japanese meals kept her slim without working out.

Surprisingly, top of her list is home cooked meals - and not eating out. Japanese women are masters of simple home cooking which hold great appreciation. The classic home cooked meal is a piece of grilled fish with steamed rice and simmered vegetables, accompanied by a bowl of hot miso soup, to be finished off with sliced fresh fruit and a cup of hot green tea - considerably easier than the sushi and sashimi that leap into mind when westeners think of Japanese food!

Small portions of food are served on beautiful, small tableware - very important in Japan - and exercise forms a daily part of life - walking, bike riding and gardening.

Food variety

I n Japan, dietary guidelines recommend to consume at least 30 different foods daily, a ruling unique to Japan. While other countries stress variety (especially when it comes to vegetables and fruit), only Japan has gone so far as to quantify an actual number to aim for.

According to Nutrition Australia, people who eat a wide variety of foods are healthier, have a reduced risk of heart disease and diabetes and live longer. And they're more likely to meet their nutrient needs, particularly important for the over 50s.

They estimate the average Australian eats only 15 to 18 different foods per week, well below what the Japanese suggest.

The salt trap

The single bad aspect is the saltiness. Salty sauces such as soy sauce, teriyaki sauce or oyster sauce take the place of salt in Japan and impart a wonderful flavour. But don't overdo them as they can send your overall salt intake sky high which sets the scene for high blood pressure and stomach cancer - two health concerns in certain regions of Japan.

6 key foods in the Japanese diet and why they're good for you

FISH

F ish is the meat of Japan. Nearly 10 per cent of the world's fish is consumed by the Japanese, yet they make up only 2 per cent of the world's population. Salmon is the most sought after, followed closely by tuna. Both are excellent sources of omega-3 fats, essential for a healthy heart and mind.

VEGETABLES

Packed with vitamins, minerals and phyto-nutrients, vegetables are low fat, low kilojoule and high fibre. They fill you up and stop you eating too much.

RICE

Short grain white rice is the Japanese staple. Rich in carbohydrates, it has little sodium (salt), saturated fat, trans fat or cholesterol. Plain rice is a must-have food with every meal. It's filling and replaces many less nutritious alternatives in other cuisines - think creamy mash, bread with butter, or pasta in a heavy sauce. A tip for how you can eat even more healthily than the average Japanese is to capitalise on the expert advice to 'eat more whole grains': eat brown rice!

SOY BEANS

Miso soup, edamame, tofu, natto beans. The Japanese consume an average of 50 grams of soy per day compared to less than 5 grams for the average Westerner. Women in Japan have very low rates of breast cancer and men have lower rates of prostate cancer than women or men in Australia - thanks in part to the isoflavonoids plant hormones from soy. These are natural substances which mimic the action of the female hormone oestrogen and "block" its cancer-promoting ability.

A recent study found that Japanese men had much higher levels of isoflavonoid in their blood compared to Finnish men due to their liking for tofu.

NOODLES

Like rice, noodles are another staple. They are low in fat and full of filling carbohydrate. The Japanese cook noodles made from mung beans and buckwheat (soba), not just wheat.

TEA

The flavonoids from green tea help the Japanese avoid heart troubles and live longer.

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Lessons from Japan - Eat like a Japanese - Catherine Saxelby's Foodwatch

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The traditional Japanese diet comes close to the perfect diet - and it's delicious too. Sashimi, prawn tempura, chicken teriyaki, beef yakitori and seafood ramen noodle soup. There's lots to love about Japanese food. It's light, fresh and flavoursome. And here's the best reason of all - it's one of the healthiest cuisines to eat in the world.

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"Governmental authorities and institutions in developed countries have long recommended reductions in the intake of dietary fat. Recommendations are derived mainly from the associations of higher intakes of fat and its components with risks of cardiovascular disease, overweight, and cancer, although such associations have not necessarily been supported in subsequent studies. In recent years, greater emphasis has been placed on the reduction of saturated fatty acid and trans-fatty acid intakes rather than total fat..."

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¹From the Laboratory of Food Science, Kyushu University School of Agriculture, Fukuoka, Japan, and the Division of Food Science, National Institute of Health and Nutrition, Tokyo.

Abstract

The amount of polyunsaturated fatty acids (PUFAs) in the food chain in Japan is reviewed on the basis of the newest nutrition survey data. The Japanese are currently consuming, on average, ≈26% of energy as fats with ratios of polyunsaturated to saturated fats and n−6 to n−3 fatty acids of ≈1.2:1 and 4:1, respectively. The significant contributors to this relatively high n−3 PUFA intake are not only fish and shellfish but also edible vegetable oils, almost exclusively rapeseed and soybean oils. Thus, the dietary habits of the Japanese have made possible a high n−3 PUFA intake within a low-fat regimen. In this context, the gradual decline, particularly in younger persons, in fish consumption habits weighs on our minds. Analyses of health indexes, including the increased average life span, support the superiority of the current Japanese eating pattern that harmonizes with the Western regimens. However, at present it cannot be disregarded that food intake varies considerably in all age groups, and only a limited number of people are consuming the recommended allowance for dietary fats.

INTRODUCTION

Japan has one of the lowest intakes of fat in the world ( 1). The average current fat intake in Japan, just below 60 g/d or 26% of energy, approximates the upper limit of the recommended dietary allowance (RDA) for fat, which is 25% of energy ( 2). These intake levels are obviously lower than those of most Western countries. In addition, because the National Nutrition Survey is conducted in Japan every year ( 3), current information is always available on the nutrient intake at the national level. The RDAs are revised every 5 y ( 2), enabling up-to-date comparisons of fat intake with RDAs.

Although the physiologic significance of the current nutritional intake of the Japanese is difficult to evaluate, it seems likely that the nutrient intake pattern contributes at least in part to the life expectancy of the Japanese, which is the longest in the world ( 4). It is in turn true that the rapid westernization of Japanese eating habits after World War II also provided a health benefit. Thus, this review will start with an explanation of the current trend in health patterns and fat intake in Japan.

TRENDS IN FAT INTAKE AND CAUSES OF DEATH

During the 4 decades from 1950 to 1990 there were drastic changes in the major causes of death in Japan ( Figure 1) ( 5). The most dramatic change was the reduction in the rate of death from cerebrovascular disease, which was once overwhelmingly the leading cause of death in Japan; Cerebrovascular disease peaked during the 1960s, has decreased rapidly since, and is now the third leading cause of death. The rate of death from tuberculosis also decreased to a low level. In contrast, 2 Western-type diseases, neoplasms and heart disease, increased gradually, and these are now the first and second causes of death, respectively.

Rates of death from different types of cancer changed gradually over the same period ( Figure 2), and the rate of death from stomach cancer, which had been the most common cancer in Japan, decreased, whereas rates of death from cancers of the lung, liver, large intestine, and breast increased, possibly reflecting changes in nutrient intake ( 5). Thus, the types of cancers in the Japanese are becoming more Western. The type of cerebrovascular disease is also changing, from cerebral hemorrhage to cerebral infarction. About two-thirds of Japanese deaths at present are attributed to 3 diseases: cancer, heart disease, and cerebrovascular disease. Although the pattern became westernized, the standardized death rates from cancer and heart disease are low compared with those in other major developed countries ( 5). The rate of death from cerebrovascular disease in Japan ranks at the midpoint compared with other developed countries, but the difference among the countries is relatively small compared with the difference in rates of death from cancer and heart disease.

The change in nutrient intakes ( Figure 3) is considered to be closely related to the observed change in the pattern of death rates (Figure 1). Analyses of nutrient intakes during 1950-1990 showed that there was a significant increase in fat intake during this period, from <20 to nearly 60 g/d. This dietary change appears to have been at the expense of carbohydrates, mainly rice, consumption of which fell from >400 to <300 g/d. However, fat consumption reached a plateau between 1980 and 1990.

With the increase in fat consumption came a significant change in its composition. The consumption of animal fat increased from 30% to 50% of total fats consumed, whereas that of vegetable fat decreased from 70% to 50% between 1950 and 1970; since then, the proportion of animal to vegetable fats has remained almost constant at ≈1:1. From these data, it is apparent that fat intake by Japanese has been relatively stable, at least during these 20 y. Therefore, it seems appropriate to focus on fat intake in these periods to understand polyunsaturated fatty acids (PUFAs) in the food chain in Japan.

TRENDS IN POLYUNSATURATED FATTY ACID INTAKE

The major food sources of fat in Japan are shown in Figure 4. Reflecting the trend of the fat intake pattern, the contribution of individual food groups was apparently constant from 1975 to 1994. Among dietary fat sources, edible fats and oils are the largest, contributing >25% of total dietary fats. Meats are also important fat sources, providing ≈20% of total fats. It is quite characteristic that in the Japanese diet fish and shellfish contribute ≈10% of the total fat intake. Intake of fats from milk, dairy products, and eggs is relatively low compared with that in Western countries.

Consequently, for the past 2 decades the proportion of fats in the Japanese diet from animals, vegetables, and fish has been 4:5:1. This proportion was the basis of the recommended balance of n−6 and n−3 PUFA intake in the recent RDA for fat in Japan ( 3). The proportion of dietary PUFAs showed a marked change before 1975. Since then, intake from each fatty acid group, ie, saturated, monounsaturated, and polyunsaturated, has remained constant ( Figure 5). The analyses based on the National Nutrition Survey data indicate the constancy of PUFA intake from 1975 to 1994 ( 6). The ratio of n−6 to n−3 PUFAs was essentially constant at ≈4:1 throughout this period and the ratio polyunsaturated to saturated fatty acids was ≈1:1.2. A similar trend in the PUFA intake pattern was reported earlier ( 1).

Advances in knowledge concerning physiologic functions of dietary PUFAs, in particular n−3 PUFAs, have led to deep concern about the decrease in fish consumption in Japan, although its significance is not necessarily well understood. Fish is not the "almighty" food, but it appears to provide a variety of health benefits compared with meats. For example, fish may reduce the risk of so-called adult diseases in a dose-dependent manner ( 7- 9).

Food sources of n−3 PUFAs are limited, even in Japan. Fish, shellfish, and edible fats and oils are the most important sources of n−3 PUFAs ( Figure 6). Pulses and cereals also contribute a significant portion of n−3 PUFAs. In contrast, the sources of n−6 PUFAs are more diverse. Although edible fats and oils contribute far more n−6 PUFAs than does any other food source, pulses, cereals, fish and shellfish, meats, and eggs also provide meaningful amounts of these fatty acids.

Fish and shellfish now provide 5-6 g fat and ≈1-2 g n−3 PUFA per person per day in Japan. About 60% of these fats are from fresh fish: horse mackerels, sardines, and tuna are quantitatively the most important sources. These fish are usually rich in n−3 PUFAs, in particular docosahexaenoic acid (DHA; 22:6n−3) and eicosapentaenoic acid (EPA; 20:5n−3), which constitute 15-35% of total fatty acids by weight. Not all fish are consumed raw in Japan; a considerable portion is eaten after cooking. In addition to salted and dried fish, shellfish are also good sources of n−3 PUFAs.

As mentioned previously, another aspect of the Japanese diet that contributes to the relatively high level of consumption of n−3 PUFAs is that, almost exclusively, only 2 edible vegetable oils, soybean and rapeseed oils, are consumed. These oils represent a total of 65-70% of the vegetable oils consumed ( 10) and contain α-linolenic acid.

Although the Japanese are currently eating ≈80 g fish and shellfish/d, consumption is gradually decreasing, particularly in younger persons in keeping with the westernization of their diets. The fish intake of the young is less than half that of the adult or aged population ( 2). As a result, serum lipids of young people have a higher ratio of n−6 to n−3 PUFAs, and this ratio decreases with age ( Figure 7; 11). Consequently, the ratio of EPA to arachidonic acid (AA; 20:4n−6) is the reverse of the ratio of n−6 to n−3 PUFAs. A similar pattern also was reported by Nakamura et al ( 12). The ratio of n−6 to n−3 PUFAs in dietary fat also differs depending on location within Japan and, in some cases, with one's occupation ( 10).

In the 1994 National Nutrition Survey ( 2), a question about fish intake was included. The survey found that >50% of young adults ate fish regularly. However, >60% were satisfied with their current low level of fish consumption (less than once a week).

It is possible that the fish-eating habits of the Japanese will change to an appreciable extent in the near future as a result of small but cumulative changes. Because of this, and for other reasons, we must develop a new national fish menu that appeals to the younger generation and prevents further loss of n−3 PUFAs. In this context, the report of Vatten et al ( 13) is of interest. In an epidemiologic analysis in Norwegian women, they showed no association between the overall frequency of fish for dinner and breast cancer incidence, although fish was more effective than meat in reducing breast cancer risk. However, and interestingly, they observed a borderline negative association between breast cancer incidence and the frequency of main meals containing "fish in a poached form." In contrast, no association was observed with fried fish or minced fish combined with milk and starch, ie, balls and puddings. This observation may indicate the importance of the way fish is prepared and served. The Japanese have a custom of eating raw fish, but boiled fish may be more preferable to affect certain aspects of human physiologic functions. The elucidation of the mechanisms underlying this interesting phenomenon deserves future study.

However, irrespective of this situation, the average net n−3 PUFA intake has not changed demonstrably, as described above. This is mainly due to the current preference for cultured fish over wild fish. At present, more of the fish consumed is from cultured than from wild sources; cultured fish are in general more fatty and less expensive, whereas the content of n−3 PUFAs in cultured fish is generally comparable with those of wild fish ( Table 1) ( 14). Consequently, cultured fish as a whole can provide more n−3 PUFAs than wild fish per gram consumed. Although the variety of cultured fish is increasing, the fat content of cultured fish is unfortunately gradually being reduced to the amounts contained in wild fish to give the cultured fish natural taste and texture.

DIETARY PUFA AND BLOOD FATTY ACID COMPOSITION

Reflecting these fat consumption patterns, the Japanese have higher concentrations of plasma lipid n−3 PUFAs than do the inhabitants of Western countries. An example is shown in Table 2, in which the comparisons were made between Japanese, Japanese Americans, and white Americans ( 15); n−3 PUFA concentrations were >3 times higher in the Japanese living in Japan than in the Americans. It is interesting that the proportion of n−6 PUFAs is higher in Americans than in Japanese, reflecting the difference in the ratio of n−6 to n−3 dietary fats. Similarly, breast milk from Japanese mothers contains more n−3 PUFAs, in particular DHA, than that from mothers in Western countries ( 16, 17).

RECOMMENDED DIETARY RATIO OF n−3 TO n−6 PUFAS

Several countries have recommend allowances not only for the absolute amount of PUFAs, but also the balanced intake of n−6 and n−3 PUFA. These recommendations are summarized in Table 3 ( 3, 18, 19). Although fish is an excellent source of n−3 PUFAs, fish consumption is limited in the world, and only a few countries eat fish regularly by custom. The ratio of n−6 to n−3 PUFAs of 4-10:1, which is now recommended for some Western countries, however, is without a firm theoretical basis. It may be difficult to reduce the ratio below 10:1 in these countries.

In contrast, it is not difficult to develop a menu with a ratio of n−6 to n−3 PUFAs of 3-4:1 in Japanese homes. By using a model menu, diets that contain reasonable amounts of total PUFAs (15-17 g/d) and have a ratio of n−6 to n−3 PUFAs of 3.5-4.2:1 can be prepared, even in areas in which dietary habits are considerably different ( 20).

However, this model menu cannot be generalized and the deviations from this goal are numerous. It is curious, for example, that not all students in women's nutrition colleges in Japan understand what the RDA means. Thus, as shown in Table 4, many undergraduate students in these colleges are eating more n−6 PUFAs and less n−3 PUFAs than is recommended ( 21- 25). This finding suggests a sizable diversity of PUFA intake in Japan, particularly among younger Japanese. The variation is also observed in total fat consumption. It is surprising that only 45% of Japanese families are consuming the recommended amount of fat, which is 20-25% of energy. In this sense, only a limited number of Japanese are following a healthy way of eating. Hence, a more exhaustive nutritional education effort is necessary.

The classic international comparative study by Keys ( 26) that was designed to relate customary diets to serum cholesterol concentrations and, hence, potential heart risk, revealed sizable differences in these indicators within Japan as a result of the geographic differences in eating habits. However, the difference is gradually disappearing.

Finally, we would like to comment on the role of fish as a source of calcium and vitamin D. Calcium intake in Japan has been 10% lower than the recommended amount for >20 y ( 2). In addition, >30% of Japanese have low calcium intakes. In this situation, the contribution that fish makes to calcium and vitamin D intake, ≈15% and 80% of total intake, respectively, is of great value ( 2).

In conclusion, we stress the importance of eating moderately, including fat. In this context, the Japanese way of eating, "eat more kinds of foods, but in smaller amounts," appears to be the most important instruction for our health.

Footnotes

↵ 2 Address reprint requests to M Sugano, Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto 862-8502, Japan. E-mail: suganomi{at}pu-kumamoto.ac.jp .

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Polyunsaturated fatty acids in the food chain in Japan

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1From the Laboratory of Food Science, Kyushu University School of Agriculture, Fukuoka, Japan, and the Division of Food Science, National Institute of Health and Nutrition, Tokyo. The amount of polyunsaturated fatty acids (PUFAs) in the food chain in Japan is reviewed on the basis of the newest nutrition survey data.

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Japanese children are expected to live until 73 without any major illness or disabilities according to the recent study published in the lancet. The average life expectancy is 80 for the Japanese population in todays society. 6 health lessons from the Japanese population that people can adopt to boost our overall health include:
1. choose foods with fewer calories per bite.
2. practice flexible restraint in portion sizes.
3. eat more rice instead of bread.
4. start walking 98% of Japanese people walk or ride to school. Japanese children are meeting the recommendations of children to get 60 minutes of moderate to vigorous physical activity per day just by walking to school, which sets up a life long habit of exercise.
5. encourage children to eat a wide variety of different healthy foods.
6. The importance of lunch. Japanese students are served a mid-day meal, there are no unhealthy food options available the children help prepare and serve lunch.

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Global life expectancy has risen by more than six years since 1990 as healthy life expectancy grows; ischemic heart disease, lower respiratory infections, and stroke cause the most health loss around the world.

People around the world are living longer, even in some of the poorest countries, but a complex mix of fatal and nonfatal ailments causes a tremendous amount of health loss, according to a new analysis of all major diseases and injuries in 188 countries.

Thanks to marked declines in death and illness caused by HIV/AIDS and malaria in the past decade and significant advances made in addressing communicable, maternal, neonatal, and nutritional disorders, health has improved significantly around the world. Global life expectancy at birth for both sexes rose by 6.2 years (from 65.3 in 1990 to 71.5 in 2013), while healthy life expectancy, or HALE, at birth rose by 5.4 years (from 56.9 in 1990 to 62.3 in 2013).

Healthy life expectancy takes into account not just mortality but also the impact of nonfatal conditions and summarizes years lived with disability and years lost due to premature mortality. The increase in healthy life expectancy has not been as dramatic as the growth of life expectancy, and as a result, people are living more years with illness and disability.

"Global, regional, and national disability-adjusted life years (DALYs) for 306 diseases and injuries and healthy life expectancy (HALE) for 188 countries, 1990-2013: quantifying the epidemiological transition" examines fatal and nonfatal health loss across countries. Published in The Lancet on August 27, the study was conducted by an international consortium of researchers working on the Global Burden of Disease study and led by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington.

"The world has made great progress in health, but now the challenge is to invest in finding more effective ways of preventing or treating the major causes of illness and disability," said Professor Theo Vos of IHME, the study's lead author.

For most countries, changes in healthy life expectancy for males and females between 1990 and 2013 were significant and positive, but in dozens of countries including Botswana, Belize, and Syria healthy life expectancy in 2013 was not significantly higher than in 1990. In some of those countries, including South Africa, Paraguay, and Belarus, healthy life expectancy has actually dropped since 1990. People born in Lesotho and Swaziland in 2013 could expect to live at least 10 fewer years in good health than people born in those countries two decades earlier. People in countries such as Nicaragua and Cambodia have experienced dramatic increases in healthy life expectancy since 1990, 14.7 years and 13.9 years, respectively. The reverse was true for people in Botswana and Belize, which saw declines of 2 years and 1.3 years, respectively.

The differences between countries with the highest and lowest healthy life expectancies is stark. In 2013, Lesotho had the lowest, at 42 years, and Japan had the highest globally, at 73.4 years. Even regionally, there is significant variation. Cambodians and Laotians born in 2013 would have healthy life expectancies of only 57.5 years and 58.1 years, respectively, but people born in nearby Thailand and Vietnam could live nearly 67 years in good health.

As both life expectancy and healthy life expectancy increase, changes in rates of health loss become increasingly crucial. The study's researchers use DALYs, or disability-adjusted life years, to compare the health of different populations and health conditions across time. One DALY equals one lost year of healthy life and is measured by the sum of years of life lost to early death and years lived with disability. The leading global causes of health loss, as measured by DALYs, in 2013 were ischemic heart disease, lower respiratory infections, stroke, low back and neck pain, and road injuries. These causes differed by gender: for males, road injuries were a top-five cause of health loss, but these were not in the top 10 for females, who lose substantially more health to depressive disorders than their male counterparts.

Ethiopia is one of several countries that have been rising to the challenge to ensure that people live lives that are both longer and healthier. In 1990, Ethiopians could expect to live 40.8 healthy years. But by 2013, the country saw an increase in healthy life expectancy of 13.5 years, more than double the global average, to 54.3 years.

"Ethiopia has made impressive gains in health over the past two decades, with significant decreases in rates of diarrheal disease, lower respiratory infection, and neonatal disorders," said Dr. Tariku Jibat Beyene of Addis Ababa University. "But ailments such as heart disease, COPD, and stroke are causing an increasing amount of health loss. We must remain vigilant in addressing this new reality of Ethiopian health."

The fastest-growing global cause of health loss between 1990 and 2013 was HIV/AIDS, which increased by 341.5%. But this dramatic rise masks progress in recent years; since 2005, health loss due to HIV/AIDS has diminished by 23.9% because of global focus on the disease. Ischemic heart disease, stroke, low back and neck pain, road injuries, and COPD have also caused an increasing amount of health loss since 1990.The impact of other ailments, such as diarrheal diseases, neonatal preterm birth complications, and lower respiratory infections, has significantly declined.

Across countries, patterns of health loss vary widely. The countries with the highest rates of DALYs are among the poorest in the world, and include several in sub-Saharan Africa: Lesotho, Swaziland, Central African Republic, Guinea-Bissau, and Zimbabwe. Countries with the lowest rates of health loss include Italy, Spain, Norway, Switzerland, and Israel.

Country-level variation also plays an important role in the changing disease burden, particularly for non-communicable diseases. For communicable, maternal, neonatal, and nutritional disorders, global DALY numbers and age-standardized rates declined between 1990 and 2013. While the number of DALYs for non-communicable diseases have increased during this period, age-standardized rates have declined.

The number of DALYs due to communicable, maternal, neonatal, and nutritional disorders has declined steadily, from 1.19 billion in 1990 to 769.3 million in 2013, while DALYs from non-communicable diseases have increased steadily, rising from 1.08 billion to 1.43 billion over the same period.

The study also examines the role that socio-demographic status - a combination of per capita income, population age, fertility rates, and years of schooling - plays in determining health loss. Researchers' findings underscore that this accounts for more than half of the differences seen across countries and over time for certain leading causes of DALYs, including maternal and neonatal disorders. But the study notes that socio-demographic status is much less responsible for the variation seen for ailments including cardiovascular disease and diabetes.

"Factors including income and education have an important impact on health but don't tell the full story," said IHME Director Dr. Christopher Murray. "Looking at healthy life expectancy and health loss at the country level can help guide policies to ensure that people everywhere can have long and healthy lives no matter where they live."
Countries with highest healthy life expectancy, both sexes, 2013

Countries with lowest healthy life expectancy, both sexes, 2013

1 Lesotho
2 Swaziland
3 Central African Republic
4 Guinea-Bissau
5 Zimbabwe
6 Mozambique
7 Afghanistan
8 Chad
9 South Sudan
10 Zambia

Leading causes of DALYs or health loss globally for both sexes, 2013

1 Ischemic heart disease
2 Lower respiratory infection
3 Stroke
4 Low back and neck pain
5 Road injuries
6 Diarrheal diseases
7 Chronic obstructive pulmonary disease
8 Neonatal preterm birth complications
9 HIV/AIDS
10 Malaria

###

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Life expectancy climbs worldwide but people spend more years living with illness and disability

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Global life expectancy has risen by more than six years since 1990 as healthy life expectancy grows; ischemic heart disease, lower respiratory infections, and stroke cause the most health loss around the world.

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Working Aged 18+
Workers in Japan have been studied and ranked at not being sufficiently active. A study was collected in 2012 looking at leisure time physical activity in youth to adulthood. The study found that those participated in strenuous activity when 12 have a positive association with being active in adult hood. The Japanese worker is different in important ways to them in western societies: workaholism, obedience, tolerance and selfless devotion to country are typical Japanese tendencies and may underpin why help promotion effects are inconsistent.
Figure 1 shows the percentages of workers with current participation in regular leisure-time physical activity by age group. There was a higher proportion of participation in older age groups (50s and 60s).

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Environmental Health and Preventive Medicine

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Hiroaki Itoh 1,

Fumihiko Kitamura 1,

Noriko Hagi 2,

Tomoe Mashiko 3,

Takehisa Matsukawa 1 and

Kazuhito Yokoyama 1 Email author

Environmental Health and Preventive Medicine 2017 22:37

DOI: 10.1186/s12199-017-0648-1

Received: 16 December 2016

Accepted: 22 March 2017

Published: 7 April 2017

Abstract

Background

Workers in Japan are not sufficiently active; however, it remains unclear how their leisure-time physical activity habits may be developed. This cross-sectional study investigated the relationship of age- and intensity-specific leisure-time physical activity in youth to adulthood leisure-time physical activity habits among Japanese workers.

Methods

In 2012, 968 workers (333 males and 635 females) from three companies and six hospitals in the Tokai region of Japan agreed to complete and submit a self-administered questionnaire. Intensity-specific leisure-time physical activity at ages 12 and 20 years was assessed retrospectively, and workers' current participation in regular leisure-time physical activity was assessed as an outcome measure. Multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression analysis.

Results

Mean ages for males and females were 40 and 37 years, respectively. Strenuous leisure-time physical activity at age 12 years was significantly positively associated with adulthood participation in leisure-time physical activity among male workers [adjusted OR (95% CI) = 2.29 (1.02, 5.14)]. Additionally, both strenuous and moderate physical activity at age 20 years was significantly positively associated with participation in regular leisure-time physical activity in adulthood among males and females.

Conclusions

Our results suggest that some leisure-time physical activity in youth may predict adult workers' participation in regular leisure-time physical activity in Japan. Encouragement of leisure-time physical activity in youth could therefore be an effective measure to develop adult leisure-time physical activity habits among workers.

Keywords

Physical activity Exercise Predictor Determinant Childhood Adulthood

Background

Physical activity is associated with reduced risk of many chronic diseases [ 1] including cardiovascular diseases [ 2, 3], type 2 diabetes [ 4], and several cancers [ 5, 6], in addition to all-cause mortality [ 7]. Despite such apparent benefits of physical activity, a large proportion of adults in developed countries such as Japan do not participate in regular leisure-time physical activity. The National Health and Nutrition Surveys in Japan for 1997, 2004, and 2009 revealed that 70-80% of the working generation (aged 20-59 years) were not sufficiently active (i.e., were exercising less than 30 min twice a week) [ 8]. Because workers in Japan may not have enough leisure time or be in the habit of participating in regular leisure-time physical activity, it remains unclear how their leisure-time physical activity habits could be developed.

In Western countries, a non-negligible number of studies suggest the possibility that physical activity in childhood and youth is associated with future physical activity [ 9]. Such a "carryover" may also be effective for building workers' leisure-time physical activity habits in Japan. However, previous studies have not reported consistent results [ 9- 14]; therefore, further investigation is needed. Moreover, epidemiological evidence that considers specific age and intensity of leisure-time physical activity in youth and the relationship of these variables to leisure-time physical activity habits in adults is lacking, particularly in Asian countries. The Japanese mentality is unique and differs in potentially important ways from that of Western societies. Workaholism, obedience, tolerance and selfless devotion to country are typical Japanese tendencies that may influence workers' behavioral priorities and their responses to health promotion efforts. Because it is also unclear whether leisure-time physical activity in youth predicts leisure-time physical activity in adulthood among Japanese people, an epidemiological study is needed. In addition, the optimal intensity level of leisure-time physical activity at specific ages that is necessary to develop future leisure-time physical activity habits remains to be determined. For example, experience of strenuous leisure-time physical activity in youth may build an individual's physical strength and enable them to resume leisure-time physical activity in adulthood.

The purpose of the present study was to investigate, in a sample of Japanese workers, the associations between age- and intensity-specific leisure-time physical activity in youth and participation as an adult in regular leisure-time physical activity. Whereas most previous studies have examined the association between total activity in youth and total activity in adulthood [ 10], this study focused on leisure-time physical activity. This will provide further insights for promoting a more desirable physical activity strategy, because leisure-time activity is modifiable and controllable. Furthermore, health effects of leisure-time physical activity may differ from those of work-related physical activity. In fact, higher occupational physical activity has recently been shown to have acute and chronic adverse effects, such as increased risk of cardiovascular disease and all-cause mortality, particularly among men [ 15]. Therefore, our independent evaluation of leisure-time physical activity will be informative. We used ages 12 and 20 years as representative time points for leisure-time physical activity in youth, based on the following precedents. In previous studies conducted in Australia [ 10] and Canada [ 16] that tracked physical activity, the mean age at baseline was 12 years. In another tracking study conducted in Belgium [ 17], the mean ages of the male and female follow-up samples at baseline was 20 and 22 years, respectively.

Leisure-time physical activity is defined as "physical activity performed during exercise, recreation, or any time other than that associated with one's regular occupation, housework, or transportation" [ 18, 19], and as "primarily exercise or sports-related activities" [ 20]. "Exercise and other forms of physical training are types of recreational physical activity" [ 21]. Therefore, "leisure-time physical activity" may be synonymous with "exercise." These two terms were treated impartially in the present study.

Methods

Participants

In 2012, we conducted a cross-sectional study in three companies (railway, transport, and driving school) and six hospitals in the Tokai region of Japan. We distributed a paper questionnaire to nearly all employees (mean 92%) at these workplaces. Of the 1,489 employees, 968 agreed to participate in the study (response rate 65%) and submitted completed questionnaires. The questionnaire's instructions informed respondents that their participation was voluntary and that completing and returning the questionnaire would signify their agreement to participate. The sample comprised 333 males and 635 females (mean ± SD of age were 40.0 ± 10.6 and 37.0 ± 11.7 years, respectively). Many of the participating hospital workers were nurses and practical nurses. The study procedure was approved in advance by the Institutional Review Board of the Juntendo University Faculty of Medicine, Tokyo, Japan (receipt number 813; approval letter number 2012057; May 21, 2012).

Data collection using questionnaires

The self-administered questionnaire collected information such as socio-demographic and anthropometric characteristics; lifestyle, including leisure-time physical activity; and medical history. Body mass index was calculated as weight in kilograms divided by the square of height in meters.

Exposure assessment of youth leisure-time physical activity

Intensity-specific leisure-time physical activity at 12 and 20 years was retrospectively assessed by the questionnaire. Details of this questionnaire have previously been described elsewhere [ 22]. With regard to intensity, the questionnaire first asked whether they participated in "strenuous leisure-time physical activity," with running, basketball, competitive swimming, and gymnastics provided as examples, as well as "moderate leisure-time physical activity" such as volleyball, softball, walking, and cycling. Participants were also asked to indicate how often they participated in the chosen activities, using the following six frequency categories: less than once per month, 1-3 days per month, 1-2 days per week, 3-4 days per week, 5-6 days per week, or every day of the week. For analyses, participation was transformed into a dichotomous variable: No (none) or Yes (which included "less than once per month," "1-3 days per month," "1-2 days per week," "3-4 days per week," "5-6 days per week," and "every day of the week"). This was because the number of workers with current participation in leisure-time physical activity in the present study was limited. In addition, history of participation in sports club activities, including organized school sports during preschool age, elementary school, junior high school, high school or higher professional school, and junior/technical college or university was also assessed. Although sports club activities may partly overlap the above-mentioned leisure-time physical activities at ages 12 and 20 years, they were assessed separately.

Outcome assessment of workers' leisure-time physical activity habits

The sole outcome of the present study was leisure-time physical activity in adulthood. Here, "regular leisure-time physical activity" was defined as exercising at least twice a week for 30 min per session for more than 1 year. This definition was employed in the National Health and Nutrition Survey in Japan (Ministry of Health, Labour and Welfare of Japan).[ 8] Participants answered this single question with "yes" or "no."

Statistical analysis

All statistical analyses were performed with SAS software version 9.2 for Windows (SAS Institute Inc., Cary, NC, USA). One woman who did not provide her age, height, and weight, and reported an abnormally high physical activity level was excluded from the analysis. For comparisons of workers' characteristics according to current participation in leisure-time physical activity, we used Wilcoxon rank sum test for continuous variables and Fisher's exact probability test for categorical variables. Unconditional logistic regression analysis was performed to calculate multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) using the SAS LOGISTIC procedure. In this analysis, workers' current participation in leisure-time physical activity was entered as a dependent variable, while leisure-time physical activity in youth was entered as an independent variable. The ORs were adjusted for age (continuous variable) and education (dummy variable). We considered these variables to be potential confounders. Educational level was controlled because of a recent related finding [ 23]. However, we did not consider the number of holidays as a potential confounder based on causal diagrams [ 24]; indeed, the number of holidays availed by the workers in recent times would not affect their leisure-time physical activity habits in youth. All analyses were performed by sex, and observations with missing or disallowed values were not used for multivariable analyses (listwise case deletion). All p values and 95% CIs were two-sided, and significance was accepted at p < 0.05. When we used leisure-time physical activity at age 20 years as an exposure variable, the participants under 20 years of age (four men and one woman) were excluded from the analysis.

Results

Table 1 shows participants' basic characteristics according to current participation in leisure-time physical activity by sex. There were no significant differences by current participation in leisure-time physical activity, with the exception of the number of holidays. Women participating in current leisure-time physical activity had more holidays than women without current participation in leisure-time physical activity, and women had more holidays than men.

Educational level, n (%)

0.58

1.00

Figure 1 shows the percentages of workers with current participation in regular leisure-time physical activity by age group. There was a higher proportion of participation in older age groups (50s and 60s).

Table 2 shows the ORs and 95% CIs for workers' current participation in regular leisure-time physical activity by intensity levels of age-specific leisure-time physical activity. We found that strenuous leisure-time physical activity at age 12 years was significantly positively associated with current participation in leisure-time physical activity among male workers [adjusted OR (95% CI) = 2.29 (1.02, 5.14)]. In contrast, female leisure-time physical activity at age 12 years was not significantly associated with adulthood participation in regular leisure-time physical activity. Moreover, strenuous and moderate leisure-time physical activity at age 20 years were also significantly positively associated with workers' current participation in regular leisure-time physical activity, and this held true for both males and females.

At age 12 years

Yes

18

109

2.29 (1.02, 5.14)

15

169

1.40 (0.69, 2.81)

At age 20 years

Yes

13

61

2.35 (1.04, 5.27)

11

42

4.93 (2.18, 11.13)

Yes

17

86

2.63 (1.16, 5.94)

16

103

2.37 (1.17, 4.79)

Table 3 shows ORs and 95% CIs for workers' current participation in regular leisure-time physical activity by history of participation in sports club activities at a young age. Female participation in such activities during high school or higher professional school was significantly positively associated with their current participation in regular leisure-time physical activity [adjusted OR (95% CI) = 3.21 (1.54, 6.68)]. In addition, female sports club activity in junior/technical college or university was also associated with participation in adulthood leisure-time physical activity. Point estimates for other ORs ranged from 1.16 to 2.18, although they were statistically insignificant.

During preschool

During elementary school

During junior high school

During high school or higher professional school

During junior/technical college or university

The direction and significance of the ORs in Tables 2 and 3 were unchanged after additionally adjusting for type of business (railway, transport, driving school, and hospital), night shift work, and the number of holidays (data not shown), with the exception of male sports club activity during high school or higher professional school [adjusted OR (95% CI) = 2.54 (1.04, 6.21)].

Discussion

Among Japanese workers, some leisure-time physical activities in youth were significantly positively associated with participation in regular leisure-time physical activity in adulthood. In particular, male strenuous leisure-time physical activity at 12 years old was positively associated with adulthood leisure-time physical activity. Strenuous and moderate leisure-time physical activities at age 20 years were also predictive of workers' current leisure-time physical activity behavior. Associations were evident and most were relatively strong in magnitude and consistent in direction. To our knowledge, this is the first study to investigate the association between leisure-time physical activity in youth and in adulthood among workers in an Asian country, also taking age- and intensity-specific activity into account. Although we only considered leisure-time physical activity, exposure in youth was a predictor of adult leisure-time physical activity in our Japanese sample. There is supportive evidence from a study in Australia reporting that childhood sport participation predicted adult physical activity, while total physical activity in childhood did not predict adult activity [ 10].

In this study, workers were distributed over a wide age range. Workers in older age groups tended to participate in regular leisure-time physical activity. This tendency is consistent with that observed in Japan's National Health and Nutrition Survey [ 8]. Such change in behavior might be attributed in part to health consciousness and increased leisure time, given that those in older age groups no longer needed to care for young children.

Different intensities of leisure-time physical activity in youth were predictive of future leisure-time physical activity behavior. For males, strenuous leisure-time physical activity at age 12 years had a greater lingering effect than did moderate activity. Plausibly, children who engaged in strenuous leisure-time physical activity would gain physical strength more easily, enabling them to participate in future leisure-time physical activity. Additionally, because moderately intense leisure-time physical activity is often more accessible, safer, and more convenient, this level of activity at age 20 years may easily lead to lifelong participation. Our age- and intensity-specific analyses revealed that both strenuous and moderate intensity leisure-time physical activity at age 20 years was effective in developing future leisure-time physical activity habits. Thus, an age- and intensity-specific analysis can provide useful insights for leisure-time physical activity promotion strategies.

A sex difference in the results at age 12 was clearly observed. Such weaker associations in females may be attributed in part to major transitions in their life course, such as the transition from schooling to employment, from singlehood to marriage and having children, or experiencing unemployment [ 9]. Such events usually have different influences, particularly on continuous employment, for males and females in Japan. These findings regarding sex difference are supported by evidence from the majority of previous studies in Western countries. These studies also tend to show that childhood physical activity positively predicts adulthood physical activity in males, whereas about half of the associations are non-significant in females [ 9]. This tendency may be common in developed countries beyond the sphere of their residential area and local mindset.

Females' sports club activity during high school or above was significantly positively associated with regular participation in adult leisure-time physical activity. This was not the case for males, although the point estimate of the OR was high. The small sample size of the subgroup might have led to the null result. Furthermore, with regard to sports club activities prior to high school in both male and female participants, no significant associations were seen. It is known that physical activity in the distant past generally shows a weaker correlation with adulthood physical activity than does activity the near past [ 11]. Another possible explanation for the lack of a significant association between sports club activities at a younger age and participation in leisure-time physical activity in adulthood is that some students who did not participate in organized school sports might have participated in other leisure-time physical activities and physical education. Although a previous study conducted in the United States [ 13] reported that the frequencies of forced and encouraged exercise during the preteen years were inversely associated with adult physical activity, such an association was not observed in the present study. Therefore, sports club activity may also be recommended for young people in Japan.

From a descriptive perspective, Tables 2 and 3 show that most workers who had participated in leisure-time physical activity in youth were not currently participating in regular leisure-time physical activity. For example, of the 127 male workers who had participated in strenuous leisure-time physical activity at age 12 years, 109 did not exercise regularly in adulthood. This suggests that continuing or resuming leisure-time physical activity in adulthood might not have been easy for the participating workers. Further studies are needed to investigate the kind of work environment that supports their participation in leisure-time physical activity.

Major strengths of the present study were as follows. Our questionnaire for assessing exposure to leisure-time physical activity at a young age took into consideration the intensity, frequency and timing of leisure-time physical activity. Workers' current participation in regular leisure-time physical activity was clearly defined in terms of frequency and duration. Whereas most previous studies have examined the association between total activity in youth and in adulthood, the present study focused on leisure-time physical activity.

Several potential limitations of the study also warrant mention. First, we carried out multiple comparisons, which might have led to some false-positive results. However, we did not apply the Bonferroni correction because we considered this method too conservative. Second, owing to the cross-sectional nature of this investigation and self-reported measures of leisure-time physical activity habits in youth, we cannot completely rule out the possibility of error owing to recall bias. However, the reliability of long-term recall of participation in physical activity has been investigated in the United States and modest correlations have been reported [ 25]. Third, the response rate was suboptimal. However, the evidence for the relationship between low response rate and non-response bias is generally weak [ 26]; therefore, our moderate response rate may not necessarily indicate non-response bias. Fourth, the sample in the present study may not be representative of the general working population in Japan; therefore, our findings may not be applicable to a wide range of Japanese workers, although the observed associations were similar to those in previous studies. Although a disproportionate number of female participants (74.8%) were night-shift workers, this type of work is common in modern society. In developed countries, about 20% of the working population is engaged in shift work [ 27]. More detailed information regarding the type of work may provide further insights when assessing these associations. In addition, our sample size was not large enough to allow dose-response analysis using the frequency of leisure-time physical activity in youth, as well as subgroup analyses by age groups. A larger study sample that enables such analyses should be considered for future studies. In addition, timing of assessment of leisure-time physical activity in youth at ages other than 12 and 20 years may be useful, as the effects of leisure-time physical activity at other ages might differ from those in transitional years such as ages 12 and 20 years.

Conclusions

In conclusion, our results suggest that certain aspects of leisure-time physical activity in youth may predict current participation in regular leisure-time physical activity in Japanese workers. Nurturing leisure-time physical activity in youth may be an effective measure to develop the future leisure-time physical activity habits of adult workers.

Abbreviations

CI:

Confidence interval

OR:

Odds ratio

Declarations

Acknowledgments

This work was funded by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) - Supported Program for the Strategic Research Foundation at Private Universities, 2011-2015.

Funding

This work was funded by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) - Supported Program for the Strategic Research Foundation at Private Universities, 2011-2015.

Availability of data and materials

Data cannot be shared due to privacy issues.

Authors' contributions

HI developed the research question, contributed to preparing the questionnaire, conducting the literature survey, cleaning the data, performing the statistical analyses, interpreting the data, and preparing the manuscript. FK created the data collection plan, contributed to questionnaire preparation and helped to prepare the manuscript. NH and T Mashiko contributed to preparing the questionnaire, created the data collection plan, and conducted data collection. T Matsukawa prepared an application for the Institutional Review Board, contributed to questionnaire preparation, and helped to prepare the manuscript. KY contributed to questionnaire preparation, data interpretation, and the preparing of the manuscript. All authors approved the final manuscript.

Competing interests

The authors declare that they have no conflict of interest.

Consent for publication

Not applicable.

Ethics approval and consent to participate

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments, or comparable ethical standards. Return of the questionnaire implied informed consent, although no written informed consent was obtained. The study procedure was approved in advance by the Institutional Review Board of the Juntendo University Faculty of Medicine, Tokyo, Japan (receipt number 813; approval letter number 2012057; May 21, 2012).

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Authors' Affiliations

(1)

Department of Epidemiology and Environmental Health, Juntendo University Faculty of Medicine

(2)

Yokkaichi Nursing and Medical Care University

(3)

Clinical Research Support Center, The University of Tokyo Hospital

References

1. Suzuki R, Iwasaki M, Yamamoto S, Inoue M, Sasazuki S, Sawada N, Yamaji T, Shimazu T, Tsugane S. Leisure-time physical activity and breast cancer risk defined by estrogen and progesterone receptor status--the Japan Public Health Center-based Prospective Study. Prev Med. 2011;52:227-33. doi:10.1016/j.ypmed.2011.01.016 .

2. Miyachi M. Measures of physical activity and exercise for health promotion by the Ministry of Health, Labour and Welfare. J Phys Fitness Sports Med. 2012;1:467-72. doi:10.7600/jpfsm.1.467 .

3. Suzuki K. What past sports experiences are necessary to establish lifelong exercise habits? : Past sports experiences before adulthood for establishing lifelong exercise habits (in Japanese). Jap J Hum Growth Developm Res. 2009;41:1-9. doi:10.5332/hatsuhatsu.2009.41_1 .

4. Taylor WC, Blair SN, Cummings SS, Wun CC, Malina RM. Childhood and adolescent physical activity patterns and adult physical activity. Med Sci Sports Exerc. 1999;31:118-23.

5. US Centers for Disease Control and Prevention (CDC). Prevalence of physical activity, including lifestyle activities among adults--United States, 2000-2001. MMWR Morb Mortal Wkly Rep. 2003;52:764-9.

6. World Cancer Research Fund / American Institute of Cancer Research. Food, nutrition, physical activity and the prevention of cancer: a global perspective. Washington: AICR; 2007.

7. Greenland S, Pearl J, Robins JM. Causal diagrams for epidemiologic research. Epidemiology. 1999;10:37-48.

8. Blair SN, Dowda M, Pate RR, Kronenfeld J, Howe Jr HG, Parker G, Blair A, Fridinger F. Reliability of long-term recall of participation in physical activity by middle-aged men and women. Am J Epidemiol. 1991;133:266-75.

9. Choung R, Locke III GR, Schleck C, Ziegenfuss J, Beebe T, Zinsmeister A, Talley N. A low response rate does not necessarily indicate non-response bias in gastroenterology survey research: a population-based study. J Public Health. 2013;21:87-95. doi:10.1007/s10389-012-0513-z .

10. Goldberg DP. The detection of psychiatric illness by questionnaire: A technique for the identification and assessment of non-psychotic psychiatric illness, Maudsley Monograph, vol. 21. London: Oxford University Press; 1972.

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# data[].attributes.attachment_link.title
Leisure-time physical activity in youth as a predictor of adult leisure physical activity among Japanese workers: a cross-sectional study

# data[].attributes.attachment_link.description
Workers in Japan are not sufficiently active; however, it remains unclear how their leisure-time physical activity habits may be developed. This cross-sectional study investigated the relationship of age- and intensity-specific leisure-time physical activity in youth to adulthood leisure-time physical activity habits among Japanese workers.