Key study question: to evaluate the prevalence of lactose intolerance (LI) in patients with Hashimoto’s thyroiditis (HT) and the effects of lactose restriction on thyroid function in these patients.

Key finding: Thirty-eight patients with lactose-intolerance (LI) were started on a lactose-restricted diet for 8 weeks. Thirty-eight patients with LI (30 euthyroid and 8 with subclinical hypothyroidism), and 12 patients without LI were included in the final analysis. The level of TSH significantly decreased in the euthyroid and subclinical hypothyroid patients with LI [from 2.06 ± 1.02 to 1.51 ± 1.1 IU/mL and from 5.45 ± 0.74 to 2.25 ± 1.88 IU/mL, respectively (both P < 0.05)]. This indicates a possible relation between thyroid disorders and malabsorption syndromes, and potential benefit from modifying diets accordingly.

Lactose intolerance occurs at a high frequency in hypothyroid patients. Lactose restriction leads to decreased levels of thyroid-stimulating hormone (TSH), and LI should be considered in hypothyroid patients who require increasing LT4 doses, have irregular TSH levels and are resistant to LT4 treatment.

This study is important because it shows a very valuable way that vitamin D supplementation can impact the muscular impairment for those with Graves Disease. Graves Disease commonly shows symptoms of low vitamin D levels. As with many diseases where low vitamin vitamin D levels are indicated, the correlations are firm yet the exact mechanisms and scope of impact are less well understood. Muscular impairment is commonly seen for those diagnosed with Graves Disease. This study sought to inhibit the impairments, with the hypothesis that vitamin D supplementation will aid in restoration of muscular performance in newly diagnosed and those who have been taking oral medication to combat Graves Disease and the symptoms of hyperthyroidism.

This was a double-blinded clinical trial. Recently diagnosed GD subjects and oral intake medication subjects were randomized between a treatment and control group. They received either a 2800 IU/day or the equivalent placebo. Isometric muscle strength, muscle function tests, postural stability, body and composition were measured using ThyPRO questionnaire at  baseline, 3, and 9 months.  Compared with placebo, vitamin D supplementation tended to reduce gain of lean body mass. In response to vitamin D supplementation, the oral medication intake subject group improved all baseline measurements in the 9 month period. 

Hyperthyroidism and Graves disease are plagued with a variety of symptoms associated (generally) with increased metabolism. Muscular wasting and impairments have been seen and the mechanism is less well understood. As GD develops, vitamin D levels tend to deteriorate over time. This makes sense, as the response to vitamin D ingestion was much greater in people who have been diagnosed with GD for a while. Supplementation with vitamin D could be suggested in a clinical setting as an additional way to prevent the breakdown of muscle. 

This investigated the affects of a gluten free diet on thyroid autoimmunity and function tests in women with Hashimoto’s disease.  The study is important because it is evaluating a causal link between a gluten free diet and Hasimoto’s disease.

The major finding of this study is that the gluten-free diet reduced thyroid autoimmunity and increased thyroid output in eu-thyroid (normal measurement) women with Hashimoto’s thyroiditis. The authors concluded that this is a specific effect of the gluten-free diet because in 62% of the patients, the decrease in thyroid antibody ti- ters and changes in thyroid function tests were also accompanied by disappearance of anti-tissue transglutaminase antibodies, a celiac indicator.

This being said, the study does not determine what causes the favorable effect of the gluten-free diet on thyroid autoimmunity, but the researchers noted an improvement in vitamin D status and hypothesize that this may be a reason for this effect.

In the study it was noted that the research methodology of this study was weak due it’s non-randomized nature, a limited number of research subjects and a short treatment period.  Still, the overall objective is important as other studies are supportive in similar research and the potential findings warrant continued evaluation. 

The clinical implications include looking to utilize a gluten free diet to control Hashimoto’s thyroiditis. It could help the patient to maintain normal measurements and prolong a hypothyroid presentation.  Understanding this possible causal effect could also mean that when treating a patient with celiac or thyroid disease (in this case, Hashimoto’s), it may be important to evaluate whether there is a secondary disease to be treated and balance the requirements of both diseases.  For example, a patient with Hashimoto’s disease may present with constipation, but adding fiber into the diet may need to come from very specific, gluten free sources.

It has been documented and is a common blanket recommendation that patients taking tablet forms of levothyroxine (L- T4) should avoid coffee consumption within 60 minutes of oral administration of L-T4.  L-T4 is a common medication prescribed for hypothyroidism.  This study is important because dietary behaviors can be difficult to change and the authors of this study report that almost 50% of the world’s population consumes coffee.  For coffee lovers or for those whose day must begin with coffee and who are taking the tablet form of L-T4, this study is significant because no change in intake habits/dietary habits revolving the timing of coffee consumption would be necessary! 

Identify one key finding of this study and describe how it relates to nutritional science. 

A soft gel formulation of L-T4 reduces the L-T4 malabsorption caused by coffee. As mentioned above, dietary behaviors can be difficult to change and poor adherence to medication regimens as prescribed when involving dietary behavior(s) can decrease the adherence to prescribed medication regimens.   

 

What are the clinical implications of this study? 

The study was very small and only included 8 patients with coffee-associated L-T4 malabsorption and used Italian coffee.  Although small, this study indicates that the new formulation of the L-T4 reduces malabsorption of L-T4 from coffee.  Patients with hypothyroidism, celiac disease and post-bariatric surgery could benefit from this new formulation of L-T4.

This study is important because it shows that women with a borderline functioning thyroid who are exposed to elevated levels of perchlorate are at an increased risk of producing offspring with lower than average IQ. The study investigated the use of levothyroxine therapy and found that it was not sufficient in reducing the effects of perchlorate.

A key topic from this study for me is the fact that genetics does play a role in intelligence and environmental factors can exacerbate the effects of the genetic component. Thus, there is an intricate balance among genetics, the environment, and even society that all play a role in the development of a healthy individual, in this case, specifically looking at neurologic health.
Even though the therapy wasn’t able to attenuate the condition, further research should be warranted to finding a way to treat this condition. Perchlorate is generally introduced in the body through ingesting fruits and vegetables with a high-water content. People living in an area where the use of explosives are common are at a greater risk from perchlorate exposure.

Optimal functioning of the thyroid gland is vital for the healthy cognitive development of the offspring. Monitoring the risk factors for excessive perchlorate exposure and therapy should be made available to pregnant women

 

 

This is a review article discussing the importance of iron, iodine and selenium supplementation/intake in patients with autoimmune thyroid disease. It discusses excess and deficiency of iodine as well as iron and selenium deficiencies that are correlated with autoimmune thyroid disease.

 

Both high and low amounts of dietary iodine are associated with an increased prevalence of both HT and GD.  The possible mechanisms of this are that highly iodinated thyroglobulin is immunogenic, as well as increasing the expression of intra-cellular adhesion molecule-1 on thyrocytes which can cause infiltration by mononuclear cells. This is relevant to clinical practice as many supplements that are available, are not necessarily recommended by dieticians, as they can contain megadoses of some vitamins and minerals. Consumers often think the more of a ingredient, the better, but in some causes, this over-supplementation can have deleterious effects. 

 

Since all three of the minerals discussed in this paper can be toxic at high doses, it’s important for patients to be educated on the risks of over-supplementation. Also, any time a disease state can be prevented or modified through diet, it’s important to discuss these with patients. 

 

Citation:  Grove-Laugesen D, Cramon PK, Malmstroem S, et al. Effects of Supplemental Vitamin D on Muscle Performance and Quality of Life in Graves' Disease: A Randomized Clinical Trial. Thyroid. 2020;30(5):661-671. doi:10.1089/thy.2019.0634           

                                             

Question 1:   Why is this study important?

     

Several studies have shown low Vitamin D levels in Graves’ disease in both cross sectional and observational designs. Studies then have also correlated low levels of Vitamin D with effect on development and course of Graves’ disease, specifically in relation to muscle weakness or quality of life. Some cross-sectional studies have shown an association of low vitamin D levels with poor muscle strength, thus decreases quality of life. This study is first prospective study to see if vitamin D supplementation improves muscle performance and quality of life and these outcomes were compared to response to anti-thyroid medications.         

 

Identify one key finding of this study and describe how it relates to nutritional sciences.  

After 9 months of Vitamin D supplementation, there was a decrease in muscle strength in all measures of muscle function and were statistically significant. These outcomes were significant when compared to placebo and more pronounced with anti-thyroid medications. Quality of life was also affected negatively but was not as significant as muscle strength. 

                 

What are the clinical implications of this study? 

In the subset of autoimmune diseases, we should be careful about implementing dietary changes as associations can be found between diet and disease course frequently. More specific diet focused research studies should be conducted to assess the effects on disease patterns. Even though Vitamin D, has beneficial effects generally on body metabolism, it should not be used to alleviate muscle weakness among Graves’ disease patients.      

Graves’ disease and Hashimoto’s disease are both thyroid autoimmune diseases but sit in the opposite sides: overproduction of thyroid hormones (Hyperthyroidism) and underproduction (Hypothyroidism).  This study is important because it shows four case studies of patients in their 20s to 40s in which each patient with Graves’ disease developed Hashimoto’s thyroiditis 7 to 25 years after their treatment.

This study reports about 15-20% of patients with Graves’ disease who receive thyroidectomy or discontinue anti-thyroid treatment spontaneously develop hypothyroidism from Hashimoto thyroiditis 10-15 years later, and it is often appeared from I treatment.  

Although its pathogenesis is still unclear, the clinical implication of this study is that such transition occurs when autoantibodies’ immune response is expanded, and thyroid cells are damaged by lymphocytic infiltration, resulting in hypothyroid.  

Unfortunately, this study does not describe a relationship with nutritional sciences, but if we know that medical treatment of Graves’ disease could lead the patients to Hashimoto’s disease decades later, we can advise patients the importance of diet management more seriously so that they may not have to suffer from hypothyroidism later.

 
This aim of this paper is discussion of the gastrointestinal GI) disorders that can have impact on treatment regimens for autoimmune thyroid diseases. Awareness of medication absoption in the presence of concurrent GI disease is impactful in the care and nutrition counselling of thyroid disease.

Key findings:
Patients with disorders impairing acid production (Atrophic gastritis and Helicobactor pylori infection) and patients taking medications to reduce stomach acid will need higher doses of thyroid hormone to treat their hypothyroidism. Any patient presenting with autoimmune thyroid disease should be screened for celiac disease (by historical review of symptoms) and lactose intolerance (by diet elimination and reintroduction) , and encouraged to try gluten free diet or lactose free diet, respectively, to improve absorption of thyroid treatments and quality of life. Bowel resection or other short-bowel syndromes result in malabsorption of nutrients, but also thyroid hormones, necessitating high doses to reach euthyroid status.

It is important to review patients with autoimmune thyroid disorders for gastrointestinal comorbitites that will change treatment escalation and dietary recommendations.

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Iodine deficiency and thyroid disease 

Zimmermann MB, Boelaert K. Iodine deficiency and thyroid disorders. Lancet Diabetes Endocrinol. 2015 Apr;3(4):286-95. doi: 10.1016/S2213-8587(14)70225-6. Epub 2015 Jan 13. PMID: 25591468.

 

 

An iodine deficiency impairs thyroid hormone production and can have some adverse effects causing an iodine deficiency disorder and ultimately causing cognitive impairment. Thyroid hormones are needed for neuronal migration, glial differentiation, and myelination of the central nervous system. An iodine deficiency primarily affects Africa and South Africa regions. The recommended iodine intake for adults over the age of 12 is 150 ug per day. Iodine status is assessed through urinary iodine concentration, biomarkers of function, goiter, and thyroid function tests. Unless iodized salt is available, the main source of iodine in a typical American diet has been through dairy. Iodine intake from dairy might be decreasing for several many reasons. The government regulations have lead to a restriction in iodine concentration in livestock supplements decreasing the amount in cow’s milk. In the last decade, the decrease in iodine intake from dairy products could be contributed to the re-emergence of iodine deficiency in Australia and the United Kingdom. As far as thyroid disorders and iodine intake, an excessive amount of iodine and a deficiency can lead to impaired thyroid function. If there is a deficiency in dietary iodine, thyroid function is maintained by increasing thyroidal clearance. Thyroid stimulating hormone is triggered by a deficiency in iodine intake increasing the expression of the sodium-iodide symporter to maximize uptake of iodine in thyroid cells. Populations with mild-moderate iodine deficiency have a higher prevalence of hyperthyroidism and lower mean serum TSH concentrations. Whereas populations with severe iodine deficiency have the prevalence of hypothyroidism. As populations shift from severe iodine deficiency to iodine sufficiency, there is a shift from hypothyroidism to hyperthyroidism. This paper illustrates that iodine intake id directly related to thyroid disorders and that the agriculture change has affected the iodine intake. 

 

 

Although this study only has one figure and table, the researchers show that the thyroid plays a role in cardiovascular factors. They design the experiment about how rats are related to diet in biochemistry parameters. The hypothyroid groups increase free fatty acid and endogenous thrombin potential to decline the high risk of atherosclerotic. Cardiovascular patients manage their thyroid-related food.

This study utilizes animal models to understand thyroid and cardiovascular disease correlation. The researchers provide the experiment approach, so they need to confirm that the human subjects are similar to animal models. It improves thyroid mechanisms to treat cardiovascular patients.

 

This study aimed to examine the prevalence of fructose, lactose, and sorbitol malassimilation in patients with Hashimoto thyroiditis (HT) and healthy controls. This is an important study because the researchers collected several parameters from the study’s participants and controls, such as hydrogen breath tests, lactose, sorbitol, and glucose. Additionally, the researchers used a food-frequency questionnaire (FFQ) to compare the average daily intakes of free fructose, lactose and sorbitol between patients and controls.

 

The study found a significant association between patients with HT and carbohydrate malassimilation. Moreover, the study showed that euthyroid patients with HT suffer significantly more from fructose, lactose, and gastrointestinal symptoms. This can relate to to nutritional sciences because it found a link between HT and the gastrointestinal tract. 

 

The main clinical implication of this study is that healthcare providers who treat patients with HT patients should consider the association between HT and gastrointestinal symptoms. Additionally, physicians have to perform H2-breath tests, especially if patients have gastrointestinal intolerance.