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How does carbohydrate affect your mental health?

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How does carbohydrate affect your mental health?

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Consuming low in carbohydrate can lead to depression since the production of "well-being" hormones are triggered by carbohydrate rich food.

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INTRODUCTION

Few people are aware of the connection between nutrition and depression while they easily understand the connection between nutritional deficiencies and physical illness. Depression is more typically thought of as strictly biochemical-based or emotionally-rooted. On the contrary, nutrition can play a key role in the onset as well as severity and duration of depression. Many of the easily noticeable food patterns that precede depression are the same as those that occur during depression. These may include poor appetite, skipping meals, and a dominant desire for sweet foods.[ 1] Nutritional neuroscience is an emerging discipline shedding light on the fact that nutritional factors are intertwined with human cognition, behavior, and emotions.

The most common mental disorders that are currently prevalent in numerous countries are depression, bipolar disorder, schizophrenia, and obsessive-compulsive disorder (OCD).[ 2] The dietary intake pattern of the general population in many Asian and American countries reflects that they are often deficient in many nutrients, especially essential vitamins, minerals, and omega-3 fatty acids.[ 3] A notable feature of the diets of patients suffering from mental disorders is the severity of deficiency in these nutrients.[ 3] Studies have indicated that daily supplements of vital nutrients are often effective in reducing patients' symptoms.[ 4] Supplements containing amino acids have also been found to reduce symptoms, as they are converted to neurotransmitters which in turn alleviate depression and other mental health problems.[ 4] On the basis of accumulating scientific evidence, an effective therapeutic intervention is emerging, namely nutritional supplement/treatment. These may be appropriate for controlling and to some extent, preventing depression, bipolar disorder, schizophrenia, eating disorders and anxiety disorders, attention deficit disorder/attention deficit hyperactivity disorder (ADD/ADHD), autism, and addiction.[ 4] Most prescription drugs, including the common antidepressants lead to side effects.[ 4] This usually causes the patients to skip taking their medications. Such noncompliance is a common occurrence encountered by psychiatrists. An important point to remember here is that, such noncompliant patients who have mental disorders are at a higher risk for committing suicide or being institutionalized. In some cases, chronic use or higher doses may lead to drug toxicity, which may become life threatening to the patient.[ 4] An alternate and effective way for psychiatrists to overcome this noncompliance is to familiarize themselves about alternative or complementary nutritional therapies. Although further research needs to be carried out to determine the best recommended doses of most nutritional supplements in the cases of certain nutrients, psychiatrists can recommend doses of dietary supplements based on previous and current efficacious studies and then adjust the doses based on the results obtained by closely observing the changes in the patient.[ 4]

When we take a close look at the diet of depressed people, an interesting observation is that their nutrition is far from adequate. They make poor food choices and selecting foods that might actually contribute to depression. Recent evidence suggests a link between low levels of serotonin and suicide.[ 5] It is implicated that lower levels of this neurotransmitter can, in part, lead to an overall insensitivity to future consequences, triggering risky, impulsive and aggressive behaviors which may culminate in suicide, the ultimate act of inwardly directed impulsive aggression.

Depression is a disorder associated with major symptoms such as increased sadness and anxiety, loss of appetite, depressed mood, and a loss of interest in pleasurable activities. If there is no timely therapeutic intervention, this disorder can lead to varied consequences. Patients who are suffering from depression exhibit suicidal tendency to a larger degree and hence are usually treated with antidepressants and/or psychotherapy.[ 6] Deficiencies in neurotransmitters such as serotonin, dopamine, noradrenaline, and γ-aminobutyric acid (GABA) are often associated with depression.[ 6- 11] As reported in several studies, the amino acids tryptophan, tyrosine, phenylalanine, and methionine are often helpful in treating many mood disorders including depression.[ 12- 17] When consumed alone on an empty stomach, tryptophan, a precursor of serotonin, is usually converted to serotonin. Hence, tryptophan can induce sleep and tranquility. This implies restoring serotonin levels lead to diminished depression precipitated by serotonin deficiencies.[ 8] Tyrosine and sometimes its precursor phenylalanine are converted into dopamine and norepinephrine.[ 18]

Dietary supplements containing phenyl alanine and/or tyrosine cause alertness and arousal. Methionine combines with adenosine triphosphate (ATP) to produce S-adenosylmethionine (SAM), which facilitates the production of neurotransmitters in the brain.[ 19- 22] The need of the present paradigm is, more studies shedding light on the daily supplemental doses of these neurochemicals that should be consumed to achieve antidepressant effects. Researchers attribute the decline in the consumption of omega-3 fatty acids from fish and other sources in most populations to an increasing trend in the incidence of major depression.[ 23] The two omega-3 fatty acids, eicosapentaenoic acid (EPA) which the body converts into docosahexanoic acid (DHA), found in fish oil, have been found to elicit antidepressant effects in human. Many of the proposed mechanisms of this conversion involve neurotransmitters. For instance, antidepressant effects may be due to bioconversion of EPA to leukotrienes, prostaglandins, and other chemicals required by the brain. Others hypothesize that both EPA and DHA influence neuronal signal transduction by activating peroxisomal proliferator-activated receptors (PPARs), inhibiting G-proteins and protein kinase C, in addition to calcium, sodium, and potassium ion channels. Whichever may be the case, epidemiological data and clinical studies have clearly shown that omega-3 fatty acids can effectively treat depression.[ 24] In depressed patients, daily consumption of dietary supplements of omega-3 fatty acid that contain 1.5-2 g of EPA has been shown to stimulate mood elevation. Nevertheless, doses of omega-3 higher than 3 g do not show better effects than placebos and may be contraindicative in cases, such as those taking anticlotting drugs.[ 25] In addition to omega-3 fatty acids, vitamin B (e.g., folate) and magnesium deficiencies have been linked to depression.[ 26- 28]

Randomized, controlled trials that involve folate and vitamin B12 suggest that patients treated with 0.8 mg of folic acid/day or 0.4 mg of vitamin B12/day will exhibit decreased depression symptoms.[ 27] In addition, the results of several case studies where patients were treated with 125-300 mg of magnesium (as glycinate or taurinate) with each meal and at bedtime led to rapid recovery from major depression in < 7 days for most of the patients. Previous research has revealed the link between nutritional deficiencies and some mental disorders.[ 23, 25, 29- 32]

The most common nutritional deficiencies seen in patients with mental disorders are of omega-3 fatty acids, B vitamins, minerals, and amino acids that are precursors to neurotransmitters.[ 20, 23, 24, 27, 28, 30, 33] Accumulating evidence from demographic studies indicates a link between high fish consumption and low incidence of mental disorders; this lower incidence rate being the direct result of omega-3 fatty acid intake.[ 23, 31, 32] One to two grams of omega-3 fatty acids taken daily is the generally accepted dose for healthy individuals, but for patients with mental disorders, up to 9.6 g has been shown to be safe and effective.[ 34- 36] Majority of Asian diets are usually also lacking in fruits and vegetables, which further lead to mineral and vitamin deficiencies. The significance of various nutrients in mental health, with special relevance to depression has been discussed below.

CARBOHYDRATES

Carbohydrates are naturally occurring polysaccharides and play an important role in structure and function of an organism. In higher organisms (human), they have been found to affect mood and behavior. Eating a meal which is rich in carbohydrates triggers the release of insulin in the body. Insulin helps let blood sugar into cells where it can be used for energy and simultaneously it triggers the entry of tryptophan to brain. Tryptophan in the brain affects the neurotransmitters levels.

Consumption of diets low in carbohydrate tends to precipitate depression, since the production of brain chemicals serotonin and tryptophan that promote the feeling of well being, is triggered by carbohydrate rich foods. It is suggested that low glycemic index (GI) foods such as some fruits and vegetables, whole grains, pasta, etc. are more likely to provide a moderate but lasting effect on brain chemistry, mood, and energy level than the high GI foods - primarily sweets - that tend to provide immediate but temporary relief.

PROTEINS

Proteins are made up of amino acids and are important building blocks of life. As many as 12 amino acids are manufactured in the body itself and remaining 8 (essential amino acids) have to be supplied through diet. A high quality protein diet contains all essential amino acids. Foods rich in high quality protein include meats, milk and other dairy products, and eggs. Plant proteins such as beans, peas, and grains may be low in one or two essential amino acids. Protein intake and in turn the individual amino acids can affect the brain functioning and mental health. Many of the neurotransmitters in the brain are made from amino acids. The neurotransmitter dopamine is made from the amino acid tyrosine and the neurotransmitter serotonin is made from the tryptophan.[ 5] If there is a lack of any of these two amino acids, there will not be enough synthesis of the respective neurotransmitters, which is associated with low mood and aggression in the patients. The excessive buildup of amino acids may also lead to brain damage and mental retardation. For example, excessive buildup of phenylalanine in the individuals with disease called phenylketonuria can cause brain damage and mental retardation.

ESSENTIAL FATTY ACIDS

Omega-3 fatty acids

The brain is one of the organs with the highest level of lipids (fats). Brain lipids, composed of fatty acids, are structural constituents of membranes. It has been estimated that gray matter contains 50% fatty acids that are polyunsaturated in nature (about 33% belong to the omega-3 family), and hence are supplied through diet. In one of the first experimental demonstrations of the effect of dietary substances (nutrients) on the structure and function of the brain, the omega-3 fatty acids (specially alpha-linolenic acid, ALA) were the member to take part. An important trend has been observed from the findings of some recent studies that lowering plasma cholesterol by diet and medications increases depression. Among the significant factors involved are the quantity and ratio of omega-6 and omega-3 polyunsaturated fatty acids (PUFA) that affect serum lipids and alter the biochemical and biophysical properties of cell membranes. It has been hypothesized that sufficient long chain PUFAs, especially DHA, may decrease the development of depression.[ 37] The structural and functional components of membrane in cells of brain which is a lipid-rich organ, include polar phospholipids, spingolipids, and cholesterol. The glycerophospholipids in brain consist of high proportion of PUFA derived from the essential fatty acids (EFAs), linoleic acid and α-linolenic acid. The main PUFA in the brain are DHA, derived from the omega-3 fatty acid α-linolenic acid, arachidonic acid (AA) and docosa tetraenoic acid, both derived from omega-6 fatty acid linoleic acid. Experimental studies have revealed that diets lacking omega-3 PUFA lead to considerable disturbance in neural function.[ 38] Studies by Marszalek and Lodish indicate that despite their abundance in the nervous system, DHA and AA cannot be synthesized by mammals de novo and hence they or their precursors have to be supplied through the diet and transported to the brain. During late gestation and the early postnatal period, neurodevelopment occurs at significantly rapid rates which make the supply of adequate quantity of PUFAs, particularly DHA, imperative to ensure neurite outgrowth in addition to appropriate development of brain and retina.[ 39]

Bruinsma and Taren of University of Arizona College of Public Health, Tucson, USA explored the involvement of dieting-related psychological factors as potential confounders.[ 40] They discussed studies that have both supported and contested the proposition that lowering plasma cholesterol by diet and medications contributes to depression. Research findings point out that an imbalance in the ratio of the EFAs, namely the omega-6 and omega-3 fatty acids, and/or a deficiency in omega-3 fatty acids, may be responsible for the heightened depressive symptoms associated with low plasma cholesterol. These relationships may explain the inconsistency in the results of trials on cholesterol-lowering interventions and depression. On similar lines, dieting behaviors have been associated with alterations in moods.[ 41] Dietary omega-3 fatty acids play a role in the prevention of some disorders including depression. Their deficiency can accelerate cerebral aging by preventing the renewal of membranes. However, the respective roles of the vascular component on one hand (where the omega-3s are active) and the cerebral parenchyma itself on the other, have not yet been clearly resolved. The role of omega-3 in certain diseases such as dyslexia and autism is suggested. It was omega-3 fatty acids that participated in the first coherent experimental demonstration of the effect of dietary substances (nutrients) on the structure and function of the brain. Experiments were first of all carried out on x-vivo cultured brain cells (1), then on in vivo brain cells (2), finally on physicochemical, biochemical, physiological, neurosensory, and behavioral parameters (3). These findings indicated that the nature of polyunsaturated fatty acids (in particular omega-3) present in formula milks for infants (both premature and term) determines the visual, cerebral, and intellectual abilities.[ 16]

VITAMINS

B-complex vitamins

Nutrition and depression are intricately and undeniably linked, as suggested by the mounting evidence by researchers in neuropsychiatry. According to a study reported in Neuropsychobiology,[ 42] supplementation of nine vitamins, 10 times in excess of normal recommended dietary allowance (RDA) for 1 year improved mood in both men and women. The interesting part was that these changes in mood after a year occurred even though the blood status of nine vitamins reached a plateau after 3 months. This mood improvement was particularly associated with improved vitamin B2 and B6 status. In women, baseline vitamin B1 status was linked with poor mood and an improvement in the same after 3 months was associated with improved mood.

Thiamine is known to modulate cognitive performance particularly in the geriatric population.[ 43]

Vitamin B12 (Cynocobalamin)

Clinical trials have indicated that Vitamin B12 delays the onset of signs of dementia (and blood abnormalities), if it is administered in a precise clinical timing window, before the onset of the first symptoms. Supplementation with cobalamin enhances cerebral and cognitive functions in the elderly; it frequently promotes the functioning of factors related to the frontal lobe, in addition to the language function of people with cognitive disorders. Adolescents who have a borderline level of vitamin B12 deficiency develop signs of cognitive changes.[ 43]

Folate

It has been observed that patients with depression have blood folate levels, which are, on an average, 25% lower than healthy controls.[ 44] Low levels of folate have also been identified as a strong predisposing factor of poor outcome with antidepressant therapy. A controlled study has been reported to have shown that 500 mcg of folic acid enhanced the effectiveness of antidepressant medication.[ 45] Folate's critical role in brain metabolic pathways has been well recognized by various researchers who have noted that depressive symptoms are the most common neuropsychiatric manifestation of folate deficiency.[ 46] It is not clear yet whether poor nutrition, as a symptom of depression, causes folate deficiency or primary folate deficiency produces depression and its symptoms.

MINERALS

Calcium

A recent study showed that selective serotonin uptake inhibitors (SSRIs) inhibit absorption of calcium into bones. In addition to this, the SSRIs can also lower blood pressure in people, resulting in falls which may lead to broken bones. Indiscriminate prescription of SSRIs by doctors and ingestion by patients at risk of depression or other mental health problems may put them at increased risk of fractures. Compounded by the fact that they may be aging and already taking other medications, may also predispose them to osteoporosis.[ 47]

Chromium

Many studies on the association of chromium in humans depression have been recorded[ 48, 49] which indicate the significance of this micronutrient in mental health.

Iodine

Iodine plays an important role in mental health. The iodine provided by the thyroid hormone ensures the energy metabolism of the cerebral cells. During pregnancy, the dietary reduction of iodine induces severe cerebral dysfunction, eventually leading to cretinism.

Iron

Iron is necessary for oxygenation and to produce energy in the cerebral parenchyma (through cytochrome oxidase), and for the synthesis of neurotransmitters and myelin. Iron deficiency is found in children with attention-deficit/hyperactivity disorder. Iron concentrations in the umbilical artery are critical during the development of the foetus, and in relation with the IQ in the child; Infantile anemia with its associated iron deficiency is associated with disturbance in the development of cognitive functions.[ 43] Research findings pointed out that twice as many women as men are clinically depressed. This gender difference starts in adolescence and becomes more pronounced among married women aged 25-45, with children. Furthermore, women of childbearing age experience more depression than during other times in their lives. These indicate the possible importance of iron in the etiology of depression since its deficiency is known to cause fatigue and depression. Iron deficiency anemia is associated, for instance, with apathy, depression, and rapid fatigue when exercising.[ 43]

Lithium

Lithium, a monovalent cation, was first discovered and defined by Johan August in 1817 while he did an analysis of the mineral petalite. The role of lithium has been well known in psychiatry. Half a century into its use, its choice for bipolar disorder with antimanic, antidepressant, and antisuicidal property. The therapeutic use of lithium also includes its usage as an augmenting agent in depression, scizoaffective disorder, aggression, impulse control disorder, eating disorders, ADDs, and in certain subsets of alcoholism.[ 50] But adequate care has to be taken while using lithium, the gold standard mood stabilizer, in the mentally ill. Lithium can be used in patients with cardiovascular, renal, endocrine, pulmonary, and dermatological comorbidity. The use of lithium during pregnancy and lactation, in pediatric and geriatric population needs careful observation about its toxicity.

Selenium

In a large review, Dr. David Benton of the university of Wales identified at least five studies, which indicate that low selenium intake is associated with lowered mood status.[ 51] Intervention studies with selenium with other patient populations reveal that selenium improves mood and diminishes anxiety.[ 52, 53]

Zinc

Zinc participates among others in the process of gustation (taste perception). At least five studies have shown that zinc levels are lower in those with clinical depression.[ 54] Furthermore, intervention research shows that oral zinc can influence the effectiveness of antidepressant therapy.[ 55] Zinc also protects the brain cells against the potential damage caused by free radicals.

Several studies have revealed the full genetic potential of the child for physical development and mental development may be compromised due to deficiency (even subclinical) of micronutrients. When children and adolescents with poor nutritional status are exposed to alterations of mental and behavioral functions, they can be corrected by dietary measures, but only to certain extent. It has been observed that, nutrient composition of diet and meal pattern can have beneficial or adverse, immediate or long-term effects. Dietary deficiencies of antioxidants and nutrients (trace elements, vitamins, and nonessential micronutrients such as polyphenols) during aging may precipitate brain diseases, which may be due to failure for protective mechanism against free radicals.

OTHER PHYSIOLOGICAL AND PSYCHOSOCIAL FACTORS

Another angle of viewing diet and depression involves old age, which is a time of vulnerability to unintentional weight loss, a factor that is often linked to increased morbidity and premature death. Anorexia of aging may play an important role in precipitating this, by either reducing food intake directly or reducing food intake in response to such adverse factors as age-associated reductions in sensory perception (taste and smell), poor dentition, use of multiple prescription drugs, and depression.[ 56] Marcus and Berry[ 57] reviewed malnutrition occurring in the elderly, in both institutional and community settings, due to refusal to eat. They suggest physiologic changes associated with aging, mental disorders such as dementia and depression, and medical, social, and environmental as causative factors. Currently to tackle the problem of depression, people are following the alternative and complementary medicine (CAM) interventions. CAM therapies are defined by the National Center for Complementary and Alternative Medicine as a group of diverse medical and health systems, practices, and products that are not currently considered to be a part of conventional medicine.[ 58] Mental health professionals need to be aware that it is likely that a fair number of their patients with bipolar disorder might use CAM interventions. Some clinicians judge these interventions to be attractive and safe alternatives, or adjuncts to conventional psychotropic medications.[ 59]

Current research in psychoneuroimmunology and brain biochemistry indicates the possibility of communication pathways that can provide a clearer understanding of the association between nutritional intake, central nervous system, and immune function thereby influencing an individual's psychological health status. These findings may lead to greater acceptance of the therapeutic value of dietary intervention among health practitioners and health care providers addressing depression and other psychological disorders.

REFERENCES

2. Murray CJL, Lopez AD. The global burden of disease. World Health Organization. 1996:270. [ Google Scholar]

3. American psychiatric A: Diagnostic and statistical manual of mental disorders. 4th ed. Washington DC: 2000. [ Google Scholar]

8. National Institute of Mental Health: Depression. National Institute of Mental Health. 2000. (US Department of Health and Human Services, Bethesda (MD) [reprinted September 2002]

18. Hoes MJ. L-tryptophan in depression. J Orthomolecular Psychiatry. 1982;4:231. [ Google Scholar]

19. Buist R. The therapeutic predictability of tryptophan and tyrosine in the treatment of depression. Int J Clin Nutr Rev. 1983;3:1-3. [ Google Scholar]

22. DeLeo D. S-adenosylmethionines an antidepressant: A double blind trial versus placebo. Cut Ther Res. 1987;41:865-70. [ Google Scholar]

42. Benton D, Haller J, Fordy J. Vitamin supplementation for one year improves mood. 1995;32:98-105. [[ PubMed] Google Scholar]

58. National Center for Complementary and Alternative Medicine - National Institutes of Health. 2002.

59. Andreescu C, Mulsant BH, Emanuel JE. Complementary and alternative medicine in the treatment of bipolar disorder: A review of the evidence. J Affecrt Disord. 2008 May 2; [Epub ahead of print] [[ PubMed] Google Scholar]

Articles from Indian Journal of Psychiatry are provided here courtesy of Wolters Kluwer -- Medknow Publications

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Understanding nutrition, depression and mental illnesses

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Few people are aware of the connection between nutrition and depression while they easily understand the connection between nutritional deficiencies and physical illness. Depression is more typically thought of as strictly biochemical-based or emotionally-rooted. On the contrary, nutrition can play a key role in the onset as well as severity and duration of depression.

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Monosaccharides may be linked together via condensation reactions; 2 monosaccharides monomers joined via glycosidic linkage to form disaccharides

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What is carbonhydrates ? Any classification or examples?

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Carbohydrates are macronutrients and are one of the three main ways by which our body obtains its energy. They are called carbohydrates as they comprise , and at their chemical level. Carbohydrates are essential nutrients which include sugars, fibers and starches. They are found in grains, vegetables, fruits and in milk and other dairy products. They are the basic food groups which play an important role in a healthy life.

The food containing carbohydrates are converted into glucose or blood sugar during the process of digestion by the digestive system.

Our body utilizes this sugar as a source of energy for the cells, organs and tissues. The extra amount of energy or sugar is stored in our muscles and liver for further requirement. The term 'carbohydrate' is derived from a French term 'hydrate de carbone' meaning ' hydrate of carbon '. The general formula of this class of organic compounds is .

Classification of Carbohydrates

The carbohydrates are further classified into simple and complex which is mainly based on their chemical structure and degree of polymerization.

Simple Carbohydrates (Monosaccharides, Disaccharides and Oligosaccharides)

Simple carbohydrates have one or two sugar molecules. In simple carbohydrates, molecules are digested and converted quickly resulting in a rise in the blood sugar levels. They are abundantly found in milk products, beer, fruits, refined sugars, candies, etc. These carbohydrates are called empty calories, as they do not possess fiber, vitamins and minerals.

Plants, being producers, synthesize glucose (C ₆H ₁₂O ₆) using raw materials like carbon dioxide and water in the presence of sunlight. This process of photosynthesis converts solar energy to chemical energy. Consumers feed on plants and harvest energy stored in the bonds of the compounds synthesized by plants.

Also, read more about Photosynthesis

1. Monosaccharides

Glucose is an example of a carbohydrate monomer or monosaccharide. Other examples of monosaccharides include mannose, galactose, fructose, etc. The structural organization of monosaccharides is as follows:

Monosaccharides may be further classified depending on the number of carbon atoms:

(i)Trioses (C₃H₆O₃): These have three carbon atoms per molecule. Example: Glyceraldehyde

(ii)Tetroses (C₄H₆O₄): These monosaccharides have four carbon atoms per molecule. Example: Erythrose.

Similarly, we have-

(iii) Pentoses,

(iv) Hexoses, and
(v) Heptoses
2. Disaccharides

Two monosaccharides combine to form a disaccharide. Examples of carbohydrates having two monomers include- Sucrose, Lactose, Maltose, etc.

3. Oligosaccharides

Carbohydrates formed by the condensation of 2-9 monomers are called oligosaccharides. By this convention, trioses, pentoses, hexoses are all oligosaccharides.

Complex Carbohydrates (Polysaccharides)

Complex carbohydrates have two or more sugar molecules, hence they are referred to as starchy foods. In complex carbohydrates, molecules are digested and converted slowly compared to simple carbohydrates. They are abundantly found in lentils, beans, peanuts, potatoes, peas, corn, whole-grain bread, cereals, etc.

Polysaccharides are complex carbohydrates formed by the polymerization of a large number of monomers. Examples of polysaccharides include starch, glycogen, cellulose, etc. which exhibit extensive branching and are homopolymers - made up of only glucose units.

1. Starch is composed of two components- amylose and amylopectin. Amylose forms the linear chain and amylopectin is a much-branched chain.

2. Glycogen is called animal starch. It has a structure similar to starch, but has more extensive branching.

3. Cellulose is a structural carbohydrate and is the main structural component of the plant cell wall. It is a fibrous polysaccharide with high tensile strength. In contrast to starch and glycogen, cellulose forms a linear polymer.

Functions of Carbohydrates

The main function of carbohydrates is to provide energy and food to the body and to the nervous system.

Carbohydrates are known as one of the basic components of food, including sugars, starch, and fibre which are abundantly found in grains, fruits and milk products.

Carbohydrates are also known as starch, simple sugars, complex carbohydrates and so on.

It is also involved in fat metabolism and prevents ketosis.

Inhibits the breakdown of proteins for energy as they are the primary source of energy.

An enzyme by name amylase assists in the breakdown of starch into glucose, finally to produce energy for metabolism.

Sources of Carbohydrates

1. Simple sugars are found in the form of fructose in many fruits.

2. Galactose is present in all dairy products.

3. Lactose is abundantly found in milk and other dairy products.

4. Maltose is present in cereal, beer, potatoes, processed cheese, pasta, etc.

5. Sucrose is naturally obtained from sugar and honey containing small amounts of vitamins and minerals.

These simple sugars that consist of minerals and vitamins exist commonly in milk, fruits, and vegetables. Many refined and other processed foods like white flour, white rice, and sugar, lack important nutrients and hence, they are labelled "enriched." It is quite healthy to use vitamins, carbohydrates and all other organic nutrients in their normal forms.

Carbohydrate Foods

Eating too much sugar results in an abnormal increase in calories, which finally leads to obesity and in turn low calories leads to malnutrition. Therefore, a well-balanced diet needs to be maintained to have a healthy life. That is the reason a balanced diet is stressed so much by dietitians.

Let us look into the differences between the good and bad carbohydrates.

High in Nutrients

Low in nutrients

Moderate in calories

High in calories

Low in sodium and saturated fats

High in sodium and saturated fats

Low in trans-fat and cholesterol

High in trans-fat and cholesterol

They are complex carbs. For instance: Legumes, vegetables, whole grains, fruits, and beans.

Foods considered bad carbs rarely have any nutritional value. Some of the foods include white flour, rice, pastries, sodas and processed foods.

Examples of Carbohydrates

Following are the important examples of carbohydrates:

Learn more about carbohydrates, its sources, importance, examples and other related topics at BYJU'S Biology

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Carbohydrates - Classification & Examples of Carbohydrates

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Carbohydrates are macronutrients and are one of the three main ways by which our body obtains its energy. They are called carbohydrates as they comprise , and at their chemical level. Carbohydrates are essential nutrients which include sugars, fibers and starches. They are found in grains, vegetables, fruits and in milk and other dairy products.

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How do carbohydrates impact your health?

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How do carbohydrates impact your health? - Richard J. Wood

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Monosaccharide (1 sugar unit): function as immediate energy source for cells
e.g. glucose, galatose, fructose
Disaccharides (2 sugar units): function as a transport form
e.g. lactose, maltose, and sucrose
Polysaccharides (many sugar units): may be used for energy storage/ cell structure and cell recognition
e.g. cellulose, glycogen, and starch

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Carbohydrates and the glycaemic index.

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Foods and drinks provide our body with energy in the form of carbohydrates, fat, protein and alcohol. Carbohydrates are the body's preferred energy source. The glycaemic index (GI) is a way that carbohydrates in foods and drinks are ranked according to how quickly they raise the glucose level of the blood (also known as 'blood sugar level'). It has replaced classifying carbohydrates as either 'simple' or 'complex'.

Foods with carbohydrates include bread, breakfast cereals, rice, pasta, legumes, corn, potato, fruit, milk, yoghurt, sugar, biscuits, cakes and lollies.

Digesting and absorbing carbohydrates

The digestive system breaks down carbohydrates in foods and drinks into simple sugars, mainly glucose. For example, both rice and soft drink will be broken down to simple sugars in your digestive system. This simple sugar is then carried to your body's cells through the bloodstream.

The pancreas secretes a hormone called insulin, which helps the glucose to move from your blood into the cells. Once inside a cell, the glucose is 'burned' along with oxygen to produce energy. Our brain, muscles and nervous system all rely on glucose as their main fuel to make energy.

The body converts excess glucose from food into glycogen. Glycogen acts as a storage form of glucose within the muscle tissue and the liver. Its role is to supplement blood glucose levels if they drop between meals (especially overnight) or during physical activity.

The glycaemic index (GI)

The glycaemic index (GI) is a way of ranking carbohydrate-containing foods based on how slowly or quickly they are digested and increase blood glucose levels over a period of time - usually two hours.

The GI uses glucose or white bread as a reference food - it has a GI score of 100. Carbohydrate-containing foods are then compared with this reference to assign their GI. This ensures all foods compared have the same amount of carbohydrate, gram for gram.

Carbohydrates that break down quickly during digestion have a higher glycaemic index. These high GI carbohydrates, such as a baked potato, release their glucose into the blood quickly.

Carbohydrates that break down slowly, such as oats, release glucose gradually into the bloodstream. They have low glycaemic indexes. The blood glucose response is slower and flatter. Low GI foods prolong digestion due to their slow breakdown and may help with feeling full.

GI scale examples

The terms 'low GI', 'medium GI' and 'high GI' are given to foods that fall within different ranges of the GI.

These ranges, along with some example foods, include:

low GI (less than 55) - examples include soy products, beans, fruit, milk, pasta, grainy bread, porridge (oats) and lentils

medium GI (55 to 70) - examples include orange juice, honey, basmati rice and wholemeal bread

high GI (greater than 70) - examples include potatoes, white bread and short-grain rice.

Factors that affect the GI of a food

Factors such as the size, texture, viscosity (internal friction or 'thickness') and ripeness of a food affect its GI. For instance, although both ripe and unripe bananas have a low GI (less than 55), an unripe banana may have a GI of 30, while a ripe banana has a GI of 51.

Fat, protein, soluble fibre, fructose (a carbohydrate found in fruit and honey) and lactose (the carbohydrate in milk) also generally lower a food's glycaemic response. Fat and acid foods (like vinegar, lemon juice or acidic fruit) slow the rate at which the stomach empties and slow the rate of digestion, resulting in a lower GI.

Other factors present in food, such as phytates (used to store phosphorus in plants) in wholegrain breads and cereals, may also delay a food's absorption and lower the GI.

Cooking and processing can also affect the GI - food that is broken down into fine or smaller particles will be more easily absorbed and so has a higher GI. Foods that have been cooked and allowed to cool (potatoes, for example) can have a lower GI when eaten cold than when hot (for example, potato salad compared with hot baked potato).

High GI foods are influenced by low GI foods

Generally, eating low GI foods and high GI foods at the same time has the effect of 'averaging' the GI. This is important, as most foods are eaten as part of a meal and this affects the GI value of foods. For example, eating cornflakes (a higher GI food) with milk (a lower GI food) will reduce the overall effect of the cornflakes and milk meal on blood glucose levels.

GI symbol and claims on packaged foods

You might have noticed that some packaged food products have a GI symbol or make claims about the food's GI and its health effects (for example, 'low GI to help you stay fuller for longer'). These are examples of nutrition content claims and general level health claims, allowed by Food .

The Low GI Symbol and claims about the relationship of a low GI product and its effect on health is only available to packaged food products that meet strict nutritional and testing criteria.

This labelling is not compulsory for food companies to follow, so not all products that are eligible will display the symbol or make a claim. This is often the case for smaller companies who may not have the money to go through the necessary processes to be given the label. These claims also won't generally be used on food products that would be eligible but are not typically packaged (for example, fresh fruit and vegetables).

Glycaemic Load (GL)

The amount of the carbohydrate-containing food you eat affects your blood glucose levels. For example, even though pasta has a low GI, a large serving can still cause the blood glucose levels to rise more rapidly than a smaller serving. This is what is called the glycaemic load (GL).

The GL builds on GI, as it considers both the GI of the food and the amount of carbohydrate in a portion. GL is based on the idea that a high GI food consumed in small quantities would give the same effect on blood glucose levels as larger quantities of a low GI food.

GL can be calculated easily if you know what the food's GI is and how much carbohydrate is present in the serving.

Calculating Glycaemic Load (GL)

The GL calculation is: GI x the amount of carbohydrates (in grams) in a serving of food) ÷ 100.

Using a pasta example:

GI of a standard white wheat pasta, boiled to al dente texture = 43

The carbohydrate content of a standard 180g serve = 44g

GL = 43 x 44/100 = 19g

However, if a half portion of pasta was eaten, the GL would also halve:

GI of a standard white wheat pasta, boiled to al dente texture = 43

The carbohydrate content of a half portion 90g serve = 22g

GL = 43 x 22/100 = 9.5g

Here is another example, where both foods contain the same amount of carbohydrate but their GIs are different:

A small baked potato (GI = 80, carbohydrate = 15g)

GL = 80 x 15/100 = 12g

An apple (GI = 40, carbohydrate = 15g)

GL = 40 x 15/100 = 6g

Both the small baked potato and the apple have the same amount of carbohydrate (15g). However, because their GIs differ (the apple is low while the baked potato is high), their GLs also differ, which means the baked potato will cause the blood glucose level of the person eating it to rise more quickly than the apple.
shows the GI, GL and carbohydrate content per serving of a wide variety of foods.

GI and exercise

Eating low GI foods two hours before endurance events, such as long-distance running, may improve exercise capacity. It's thought that the meal will have left your stomach before you start the event, but remains in your small intestine releasing energy for a few hours afterwards.

Moderate to high GI foods may be most beneficial during the first 24 hours of recovery after an event to rapidly replenish muscle fuel stores (glycogen).

Using the GI as a guide to healthy eating

The GI can be considered when choosing foods and drinks consistent with the , but there are limitations. For example, the GI of some everyday foods such as fruits, vegetables and cereals can be higher than foods to be eaten occasionally (discretionary) like biscuits and cakes. This does not mean we should replace fruit, vegetables and cereals with discretionary choices, because the first are rich in important nutrients and antioxidants and the discretionary foods are not.

GI can be a useful concept in making good food substitution choices, such as having oats instead of cornflakes, or eating grainy bread instead of white bread. Usually, choosing the wholegrain or higher fibre option will also mean you are choosing the lower GI option.

It's not always possible or necessary to choose all low GI foods. There is room in a healthy diet for moderate to high GI foods, and many of these foods can provide important sources of nutrients. Remember, by combining a low GI food with a high GI food, you will get an intermediate GI for that meal.

Choosing between high and low GI foods

The best carbohydrate food to eat varies depending on the person and situation. For example, people with type 2 diabetes or impaired glucose tolerance have become resistant to the action of insulin or cannot produce insulin rapidly enough to match the release of glucose into the blood after eating carbohydrate-containing foods. This means their blood glucose levels may rise above the level considered optimal.

Now consider two common breakfast foods - cornflakes and porridge made from wholegrain oats. The rate at which porridge and cornflakes are broken down to glucose is different. Porridge is digested to simple sugars much more slowly than cornflakes, so the body has a chance to respond with production of insulin, and the rise in blood glucose levels is less.

For this reason, porridge is a better choice of breakfast cereal than cornflakes for people with type 2 diabetes. It will also provide more sustained energy for people without diabetes.

On the other hand, high GI foods can be beneficial at replenishing glycogen in the muscles after strenuous exercise. High GI can also quickly restore blood glucose levels to normal when someone with diabetes is experiencing a 'hypo', which is when their blood glucose levels fall below the normal range of 4-8 mmol/L. For example, eating five jellybeans will help to raise blood glucose levels quickly. A person with diabetes is only at risk of a 'hypo' if taking certain medications or injecting insulin.

If you have a medical condition, such as diabetes, it's important to get advice from your doctor or specialist before making any changes to your diet.

Where to get help

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Foods and drinks provide our body with energy in the form of carbohydrates, fat, protein and alcohol. Carbohydrates are the body's preferred energy source. The glycaemic index (GI) is a way that carbohydrates in foods and drinks are ranked according to how quickly they raise the glucose level of the blood (also known as 'blood sugar level').

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How carbs fit into a healthy diet

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Carbohydrates: How carbs fit into a healthy diet

Carbohydrates aren't bad, but some may be healthier than others. See why carbs are important for your health and learn which ones to choose.
By Mayo Clinic Staff
Carbohydrates often get a bad rap, especially when it comes to weight gain. But carbohydrates, often called carbs, aren't all bad. Because of their many health benefits, carbs have a rightful place in the diet. In fact, the body needs carbs to work well.

But some carbs can be better for you than others. Understand more about carbohydrates and how to make healthy diet choices.

Understanding carbohydrates

Carbohydrates are a type of macronutrient found in many foods and beverages. Most carbs occur naturally in plant-based foods, such as grains. Food manufacturers also add carbs to processed foods in the form of starch or added sugar.

Common sources of naturally occurring carbohydrates include:

Types of carbohydrates

There are three main types of carbohydrates:

Sugar. Sugar is the simplest form of carbohydrate. It occurs naturally in some foods, including fruits, vegetables, milk and milk products. Types of sugar include fruit sugar (fructose), table sugar (sucrose) and milk sugar (lactose). Added sugars can be found in many foods, such as cookies, sugary drinks and candy.

Starch. Starch is a complex carbohydrate. This means it is made of many sugar units bonded together. Starch occurs naturally in vegetables, grains, and cooked dry beans and peas.

Fiber. Fiber also is a complex carbohydrate. It occurs naturally in fruits, vegetables, whole grains, and cooked dry beans and peas.

More carbohydrate terms: Net carbs and glycemic index

The terms "low carb" or "net carbs" often appear on product labels. But the Food and Drug Administration doesn't use these terms, so there's no standard meaning. Typically, the term "net carbs" is used to mean the amount of carbs in a product excluding fiber or excluding both fiber and sugar alcohols.

You probably have also heard talk about the glycemic index. The glycemic index classifies carbohydrate-containing foods according to their potential to raise blood sugar levels.

Weight-loss diets based on the glycemic index typically suggest limiting foods that are higher on the glycemic index. Foods with a relatively high glycemic index ranking include potatoes, white bread, and snack foods and desserts that have refined flours.

Many healthy foods are naturally lower on the glycemic index. Examples include whole grains, legumes, vegetables, fruits and low-fat dairy products.

How many carbohydrates do you need?

The Dietary Guidelines for Americans recommend that carbohydrates make up 45&percnt; to 65&percnt; of total daily calories.

So if you get 2,000 calories a day, between 900 and 1,300 calories should be from carbohydrates. That translates to between 225 and 325 grams of carbs a day.

You can find the carbohydrate content of packaged foods on the Nutrition Facts label. The label shows total carbohydrates - which can include fiber, total sugars and added sugars.

Carbohydrates and your health

Despite their bad reputation, carbohydrates are vital to your health for many reasons.

Providing energy

Carbohydrates are the body's main fuel source. During digestion, sugars and starches are broken down into simple sugars. They're then absorbed into the bloodstream, where they're known as blood sugar (blood glucose).

From there, glucose enters the body's cells with the help of insulin. Glucose is used by the body for energy. Glucose fuels your activities - whether it's going for a jog or simply breathing and thinking. Extra glucose is stored in the liver, muscles and other cells for later use. Or extra glucose is converted to fat.

Protecting against disease

Some evidence suggests that whole grains and dietary fiber from whole foods help lower your risk of heart disease and stroke. Fiber may also protect against obesity, colon and rectal cancers, and type 2 diabetes. Fiber is also essential for optimal digestive health.

Controlling weight

Evidence shows that eating plenty of fruit, vegetables and whole grains can help you control your weight. Their bulk and fiber content aids weight control by helping you feel full on fewer calories. Despite what proponents of low-carb diets claim, few studies show that a diet rich in healthy carbs leads to weight gain or obesity.

Choose your carbohydrates wisely

Carbohydrates are an essential part of a healthy diet, and they provide many important nutrients. Still, not all carbs are equally good for you.

Here's how to make healthy carbohydrates work in a balanced diet:

Focus on eating fiber-rich fruits and vegetables. Aim for whole fresh, frozen and canned fruits and vegetables without added sugar. Or have measured portions of fruit juices and dried fruits, which are concentrated sources of natural sugar, but have more calories. Whole fruits and vegetables have many health benefits. They add fiber, water and bulk, which help you feel fuller on fewer calories.

Choose whole grains. Whole grains are better sources than refined grains of fiber and other important nutrients, such as B vitamins. Refined grains go through a process that strips out parts of the grain - along with some of the nutrients and fiber.

Stick to low-fat dairy products. Milk, cheese, yogurt and other dairy products are good sources of calcium, protein, vitamin D, potassium, and other vitamins and minerals. Consider the low-fat versions to help limit calories and saturated fat. And watch out for dairy products that have added sugar.

Eat more beans, peas and lentils. Beans, peas and lentils are among the most versatile and nutritious foods. They are typically low in fat and high in folate, potassium, iron and magnesium. And they have useful fats and fiber. They are a good source of protein and can be a healthy substitute for meat, which has more saturated fat and cholesterol.

Limit added sugars. Added sugar probably isn't harmful in small amounts. But there's no health benefit to having any amount of added sugar, such as in cookies and pastries. The Dietary Guidelines for Americans recommend that less than 10&percnt; of calories you eat or drink every day come from added sugar. Eating or drinking too many foods with sugar can also cause you to take in more than the calories you need each day.

So choose your carbohydrates wisely. Limit foods with added sugars and refined grains, such as sugary drinks, desserts and candy. These are high in calories but low in nutrition. Instead, select fruits, vegetables and whole grains.

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Show references

1. Colditz GA. Heathy diet in adults. http://www.uptodate.com. Accessed Feb. 24, 2022.

2. Feldman M, et al. Digestion and absorption of dietary fat, carbohydrate, and protein. In: Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management. 11th ed. Elsevier; 2021. http://www.clinicalkey.com. Accessed Feb. 24, 2022.

3. Diabetes diet, eating, and physical activity. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/diabetes/overview/diet-eating-physical-activity. Accessed Feb. 24, 2022.

4. Carbohydrates - Part of a healthful diabetes diet. Academy of Nutrition and Dietetics. https://www.eatright.org/health/diseases-and-conditions/diabetes/carbohydrates-part-of-a-healthful-diabetes-diet. Accessed Feb. 24, 2022.

5. 2020-2025 Dietary Guidelines for Americans. U.S. Department of Health and Human Services and U.S. Department of Agriculture. https://www.dietaryguidelines.gov. Accessed Feb. 24, 2022.

6. Libby P, et al., eds. Nutrition and cardiovascular and metabolic diseases. In: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 12th ed. Elsevier; 2022. https://www.clinicalkey.com. Accessed Feb. 24, 2022.

7. How to understand and use the Nutrition Facts label. U.S. Food and Drug Administration. https://www.fda.gov/food/new-nutrition-facts-label/how-understand-and-use-nutrition-facts-label. Accessed Feb. 24, 2022.

8. Duyff RL. Academy of Nutrition and Dietetics Complete Food and Nutrition Guide. 5th ed. Houghton Mifflin Harcourt; 2017.

See more In-depth

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Carbohydrates aren't bad, but some may be healthier than others. See why carbs are important for your health and learn which ones to choose. By Mayo Clinic Staff Carbohydrates often get a bad rap, especially when it comes to weight gain. But carbohydrates, often called carbs, aren't all bad.