Vitamin and mineral supplements and thyroid cancer: a systematic review

Vitamin E intake and multiple health outcomes: an umbrella review

Background

The benefits of vitamin E (VE) for multiple health outcomes have been well evaluated in many recent studies.

Objective

The purpose of this umbrella review was to conduct a systematic evaluation of the possible associations between VE intake and various health outcomes.

Methods

We systematically searched various databases, such as PubMed, Embase, and the Web of Science, to identify related meta-analyses of observational studies and randomized trials. We estimated the effect size of each association by using the random or fixed effects models and the 95% confidence intervals. We used standard approaches to evaluate the quality of the articles (AMSTAR) and classified the evidence into different levels of quality (GRADE).

Results

A total of 1,974 review articles were searched, and 27 articles with 28 health outcomes were yielded according to our exclusion criteria. The intake of VE was inversely associated with the risk of breast cancer, lung cancer, esophageal cancer, gastric cancer, pancreatic cancer, kidney cancer, bladder cancer, cervical neoplasms, cardiovascular disease, Parkinson's disease, depression, age-related cataracts, metabolic syndrome, and fracture. Overall, most of the quality of the evidence was low or very low. Three outcomes (stroke, age-related cataracts, obesity) were identified as having a "moderate" level of quality. The AMSTAR scores for all health outcomes ranged from 5 to 10.

Conclusion

Our study revealed that VE intake is beneficially related to multiple health outcomes. However, future studies on recommended doses and recommended populations of VE are also needed.

Systematic review registration

http://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022339571.

Vitamin D, Thyroid Hormones and Cardiovascular Risk: Exploring the Components of This Novel Disease Triangle

The role of thyroid hormones (THs) in the cardiovascular (CV) system, through several direct and indirect effects is recognized. Even very small modification in TH levels (as those observed in subclinical hypothyroidism or hyperthyroidism, and low triiodothyronine syndrome) may adversely affect the CV system, whereas thyroid hormones benefit the CV system and improve the prognosis. There is also evidence of vitamin D effects on cardiometabolic disease (e.g., through modulation of endothelial and smooth muscle cell activity, renin-angiotensin-aldosterone system, nitric oxide, oxidative stress, and inflammatory response), as well as an association between vitamin D [25(OH)D] deficiency and autoimmune thyroid diseases or cancer, and a relationship between vitamin D concentration and titers of antibodies and thyroid autoimmunity replacement. Interestingly, experimental data indicate a direct effect of vitamin D on Type 2 deiodinase expression causing subsequential peripheral conversion of T4 into T3. However, the functional links among THs, vitamin D and the cardiovascular system, and clinical effects of coexisting abnormalities in this new troublesome triad, have not yet been reviewed. The main aim of this review is to discuss pathophysiology of this relationship, proposing new mechanistic insights involving vitamin D in the modulation of cardiometabolic disease and thyroid profile.

Dietary habits and thyroid cancer risk: A hospital-based case-control study in Sicily (South Italy)

Several studies have investigated the role of diet as a risk and/or protective factor against thyroid cancer, both considering individual foods, groups of foods and dietary patterns, but the results are not consistent. The aim of the study was to investigate the relationship between dietary habits and thyroid cancer. Cases and controls were recruited at the University Hospital "G. Rodolico" of Catania. The dietary habits were defined through the "Lifestyle Assessment Questionnaire". The frequency of consumption of each food item was reported on a 4-level scale (never, one time a week, 2-3 times a week, every day of the week). We computed the odds ratios (ORs) of thyroid cancer and the corresponding 95% confidence intervals (CIs) according to the median of control group daily intake of each food group, using multiple logistic regression models adjusted for major confounding factors. Starchy foods (OR = 1.39, 95% CI 0.83-2.32), sweets (OR = 1.39, 95% CI 0.81-2.40) and products rich in salt and fat showed a positive association with thyroid cancer risk. Conversely, an inverse association with disease risk was found for vegetables (cruciferous OR = 0.30, 95% CI 0.10-0.92, non cruciferous OR = 0.57 (0.20-1.57) milk and dairy products (OR = 0.68, 95% CI 0.40-1.13) and seafood (OR = 0.68, 95% CI 0.34-1.22). An increased risk was observed for consumption of iodized salts (OR 2.06, 95% CI 1.21-3.51), tea (OR = 1.42, 95% CI 0.84-2.41) and coca-cola (OR = 3.08, 95% CI 1.53-6.20). Finally, our results confirm the protective effect of a daily water intake of 1-2 L, but unfortunately this quantity is usually consumed by about a quarter of the sample. Dietary habits appear to modify the risk of thyroid carcinoma. A diet with a limited consumption of starchy foods, products rich in salt, fat and sugar and a higher consumption of, cruciferous/non-cruciferous vegetables, milk and dairy products and seafood could be protective towards thyroid cancer. Moreover, the water intake should be increased and the actual need to consume iodized salt should be verified for each subject/area. These results warrant further investigations and, if confirmed, they might have important public health implications for the reduction of thyroid cancer through the improvement of dietary habits.

Immunomodulatory Effects of Vitamin D in Thyroid Diseases

Vitamin D is a secosteroid with a pleiotropic role in multiple physiological processes. Besides the well-known activity on bone homeostasis, recent studies suggested a peculiar role of vitamin D in different non-skeletal pathways, including a key role in the modulation of immune responses. Recent evidences demonstrated that vitamin D acts on innate and adaptative immunity and seems to exert an immunomodulating action on autoimmune diseases and cancers. Several studies demonstrated a relationship between vitamin D deficiency, autoimmune thyroid disorders, and thyroid cancer. This review aims to summarize the evidences on the immunomodulatory effect of vitamin D on thyroid diseases.

The Role of Antioxidants in Cancer, Friends or Foes?

Consumption of dietary supplements by millions of people is increasing [1]. Between 64 to 81% of cancer patients and survivors use multivitamin supplements after the cancer diagnosis [2]. The use of antioxidants during cancer therapy has been a hot topic in medical science for the last 20 years without clear answers and recommendations. It seems that antioxidants are able to I) decrease the cancer formation risk by quenching ROS that are involved in cancer initiation and progression and II) assist in survival of cancer/precancer cells once the malignant transformation already occurred. Antioxidants were shown to assist cancer initiation, interfere with cancer treatment by reducing its efficacy and patient survival, and vice versa, there are reports of beneficial antioxidant effect during the cancer treatment.

Major dietary patterns and differentiated thyroid cancer

BACKGROUND

Differentiated Thyroid Cancer (DTC) is the most common endocrine cancer with an increasing trend worldwide. Dietary pattern as a modifiable factor may be associated with DTC.

OBJECTIVE

The present study aimed to evaluate the association between major dietary patterns and risk of DTC.

METHODS

A case control study was conducted among 309 clinic-based participants in northeast of Iran. Dietary data were then collected by a validated Food Frequency Questionnaire (FFQ). Further, codified data were analyzed by factor analysis and logistic regression analysis to identify the dietary patterns and to examine the association between dietary patterns and DTC, respectively.

RESULTS

According to our results, four major dietary patterns including western dietary pattern, traditional dietary pattern, transitional dietary pattern, and healthy dietary pattern were identified. The western dietary pattern was associated with increased odds of DTC after adjustment for potential confounders (OR = 2.79, 95% CI: 1.01-7.74). However, there was no association between other dietary patterns and DTC after adjustment.

CONCLUSIONS

In conclusion, the findings showed that western dietary pattern might be associated with DTC. Further studies are recommended to provide more conclusive evidences about the association between dietary patterns and DTC.

Consumption of fruits, vegetables and fruit juices and differentiated thyroid carcinoma risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

Fruit and vegetable (F&V) intake is considered as probably protective against overall cancer risk, but results in previous studies are not consistent for thyroid cancer (TC). The purpose of this study is to examine the association between the consumption of fruits, vegetables, fruit juices and differentiated thyroid cancer risk within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The EPIC study is a cohort including over half a million participants, recruited between 1991 and 2000. During a mean follow-up of 14 years, 748 incident first primary differentiated TC cases were identified. F&V and fruit juice intakes were assessed through validated country-specific dietary questionnaires. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression models adjusted for potential confounding factors. Comparing the highest versus lowest quartile of intake, differentiated TC risk was not associated with intakes of total F&V (HR: 0.89; 95% CI: 0.68-1.15; p-trend = 0.44), vegetables (HR: 0.89; 95% CI: 0.69-1.14; p-trend = 0.56), or fruit (HR: 1.00; 95% CI: 0.79-1.26; p-trend = 0.64). No significant association was observed with any individual type of vegetable or fruit. However, there was a positive borderline trend with fruit juice intake (HR: 1.23; 95% CI: 0.98-1.53; p-trend = 0.06). This study did not find any significant association between F&V intakes and differentiated TC risk; however a positive trend with fruit juice intake was observed, possibly related to its high sugar content.

The Role of Vitamin D in Thyroid Diseases

The main role of vitamin D is regulating bone metabolism and calcium and phosphorus homeostasis. Over the past few decades, the importance of vitamin D in non-skeletal actions has been studied, including the role of vitamin D in autoimmune diseases, metabolic syndromes, cardiovascular disease, cancers, and all-cause mortality. Recent evidence has demonstrated an association between low vitamin D status and autoimmune thyroid diseases such as Hashimoto’s thyroiditis and Graves’ disease, and impaired vitamin D signaling has been reported in thyroid cancers. This review will focus on recent data on the possible role of vitamin D in thyroid diseases, including autoimmune thyroid diseases and thyroid cancers.

Use of Dietary Vitamin Supplements and Risk of Thyroid Cancer: A Population-Based Case-Control Study in Connecticut

Certain dietary supplements have been reported to increase the risk of some cancers. Over half of the US population regularly uses dietary supplements. Thyroid cancer incidence has increased over the past several decades. However, few studies have investigated the association between dietary supplements and thyroid cancer. Thus, it is essential to clarify any association between dietary supplements and risk of thyroid cancer.

MATERIALS AND METHODS

A population-based case-control study in Connecticut was conducted during 2010-2011 among 462 histologically confi rmed incident thyroid cancer cases and 498 population-based controls. Dietary supplement intake was ascertained through in-person interviews and a food frequency questionnaire. Multivariate unconditional logistic regression models were used to estimate the risk of thyroid cancer and dietary supplement use.

RESULTS

Overall, no statistically signifi cant associations were observed between dietary supplementation and thyroid cancer risk. Stratifi ed analyses revealed a suggestive protective effect on risk of papillary microcarcinoma among longterm (> 10 years) use of multivitamins (OR = 0.59, 95 % CI: 0.33, 1.04) and calcium supplementation (OR = 0.45, 95 % CI: 0.22, 0.93). An increased risk of large papillary thyroid cancers (tumor size > 1 cm) was observed among short-term (< 5 years) users of calcium supplements (OR = 2.24, 95 % CI: 1.30, 3.88).

DISCUSSION

No signifi cant associations were observed between supplementation and overall thyroid cancer risk. The different associations between calcium supplements and risk of papillary thyroid cancer by tumor size warrant further investigation.

Serum vitamin D3 levels are not associated with thyroid cancer prevalence in euthyroid subjects without autoimmune thyroid disease

BACKGROUND/AIMS

Previous studies have suggested that elevated serum vitamin D levels might protect against thyroid cancer. Elevated serum thyroid stimulating hormone levels and autoimmune thyroid disease (AITD) are suggested to be thyroid cancer promoting factors but have not been well controlled in previous studies. We designed the present study to evaluate whether serum vitamin D levels are associated with thyroid cancer in euthyroid patients with no clinical evidence of AITD.

METHODS

This cross-sectional study included subjects who underwent routine health check-ups, including serum 25-hydroxy vitamin D3 (25(OH)D3) levels, anti-thyroid peroxidase antibody (TPO-Ab), and thyroid ultrasonography (US). Inclusion criteria were euthyroid, negative TPO-Ab, and no evidence of AITD by US findings. Thyroid cancer diagnoses were based on fine needle aspiration cytology and/or postsurgical histopathological findings.

RESULTS

We enrolled 5,186 subjects (64% male, 37% female) in this study, including 53 patients (1%) with a diagnosis of thyroid cancer (33 males, 20 females). Mean 25(OH)D3 levels were similar between the thyroid cancer and control groups (p = 0.20). Subgroup analysis according to sex or seasonal variation also revealed no differences in 25(OH)D3 levels between the two groups. Based on the levels of 25(OH)D3, there was no significant difference in the prevalence of thyroid cancer; the prevalence was 0.71%, 0.94%, 1.40%, and 0.82% in the deficient, insufficient, sufficient, and excess groups, respectively (p = 0.64).

CONCLUSIONS

The levels of serum 25(OH)D3 are not associated with thyroid cancer prevalence in euthyroid subjects with no clinical evidence of AITD.

Spatiotemporal Co-existence of Female Thyroid and Breast Cancers in Hangzhou, China

Thyroid and breast cancers (TC, BC) are common female malignant tumors worldwide. Studies suggest that TC patients have a higher BC risk, and vice versa. However, it has not been investigated quantitatively if there is an association between the space-time TC and BC incidence distributions at the population level. This work aims to answer this question. 5358 TC and 8784 BC (female) cases were diagnosed in Hangzhou (China, 2008-2012). Pearson and Spearman rank correlation coefficients of the TC and BC incidences were high, and their patterns were geographically similar. The spatiotemporal co-existence of TC and BC distributions was investigated using the integrative disease predictability (IDP) criterion: if TC-BC association is part of the disease mapping knowledge bases, it should yield improved space-time incidence predictions. Improved TC (BC) incidence predictions were generated when integrating both TC and BC data than when using only TC (BC) data. IDP consistently demonstrated the spatiotemporal co-existence of TC and BC distributions throughout Hangzhou (2008-2012), which means that when the population experiences high incidences of one kind of cancer attention should be paid to the other kind of cancer too. The strength of TC-BC association was measured by the IDP coefficients and incidence prediction accuracy.

Association between nutrient intake and thyroid cancer risk in Korean women

BACKGROUND/OBJECTIVES

The incidence of thyroid cancer has increased in many countries, including Korea. International differences in the incidence of thyroid cancer may indicate a role of diet, but findings from previous studies are inconclusive. Therefore, we aimed to investigate the roles of nutrients in thyroid cancer risk in Korean women.

SUBJECTS/METHODS

We conducted a case-control study comprising 113 cases and 226 age-matched controls. Nutrient intake was assessed using a validated food frequency questionnaire, and the association between nutrient intake and thyroid cancer risk was estimated using a logistic regression model.

RESULTS

We found that high calcium intake was associated with a reduced risk of thyroid cancer (OR [95% CI] = 0.55 [0.35-0.89]). Significant associations were observed among subjects who were older than 50 years, had low BMI, and had low calorie intake. However, other nutrients included in this study did not show any significant associations with thyroid cancer risk.

CONCLUSIONS

This study suggested a possible protective effect of calcium on thyroid cancer risk. Well-designed prospective studies are required to confirm these findings.

Energy and macronutrient intake and risk of differentiated thyroid carcinoma in the European Prospective Investigation into Cancer and Nutrition study

Incidence rates of differentiated thyroid carcinoma (TC) have increased in many countries. Adiposity and dietary risk factors may play a role, but little is known on the influence of energy intake and macronutrient composition. The aim of this study was to investigate the associations between TC and the intake of energy, macronutrients, glycemic index (GI) and glycemic load in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. The study included 477,274 middle-age participants (70.2% women) from ten European countries. Dietary data were collected using country-specific validated dietary questionnaires. Total carbohydrates, proteins, fats, saturated, monounsaturated and polyunsaturated fats (PUFA), starch, sugar, and fiber were computed as g/1,000 kcal. Multivariable Cox regression was used to calculate multivariable adjusted hazard ratios (HR) and 95% confidence interval (CI) by intake quartile (Q). After a mean follow-up time of 11 years, differentiated TC was diagnosed in 556 participants (90% women). Overall, we found significant associations only with total energy (HRQ4 vs .Q1 , 1.29; 95% CI, 1.00-1.68) and PUFA intakes (HRQ4 vs .Q1 , 0.74; 95% CI, 0.57-0.95). However, the associations with starch and sugar intake and GI were significantly heterogeneous across body mass index (BMI) groups, i.e., positive associations with starch and GI were found in participants with a BMI ≥ 25 and with sugar intake in those with BMI < 25. Moreover, inverse associations with starch and GI were observed in subjects with BMI < 25. In conclusion, our results suggest that high total energy and low PUFA intakes may increase the risk of differentiated TC. Positive associations with starch intake and GI in participants with BMI ≥ 25 suggest that those persons may have a greater insulin response to high starch intake and GI than lean people.

The association between selenium and other micronutrients and thyroid cancer incidence in the NIH-AARP Diet and Health Study

BACKGROUND

Selenium is an essential trace element that is important for thyroid hormone metabolism and has antioxidant properties which protect the thyroid gland from oxidative stress. The association of selenium, as well as intake of other micronutrients, with thyroid cancer is unclear.

METHODS

We evaluated associations of dietary selenium, beta-carotene, calcium, vitamin D, vitamin C, vitamin E, folate, magnesium, and zinc intake with thyroid cancer risk in the National Institutes of Health - American Association of Retired Persons Diet and Health Study, a large prospective cohort of 566,398 men and women aged 50-71 years in 1995-1996. Multivariable-adjusted Cox proportional hazards regression was used to examine associations between dietary intake of micronutrients, assessed using a food frequency questionnaire, and thyroid cancer cases, ascertained by linkage to state cancer registries and the National Death Index.

RESULTS

With the exception of vitamin C, which was associated with an increased risk of thyroid cancer (HR(Q5 vs Q1), 1.34; 95% CI, 1.02-1.76; P(trend), <0.01), we observed no evidence of an association between quintile of selenium (HR(Q5 vs Q1), 1.23; 95% CI, 0.92-1.65; P(trend), 0.26) or other micronutrient intake and thyroid cancer.

CONCLUSION

Our study does not suggest strong evidence for an association between dietary intake of selenium or other micronutrients and thyroid cancer risk. More studies are needed to clarify the role of selenium and other micronutrients in thyroid carcinogenesis.

Dietary magnesium intake and risk of cancer: a meta-analysis of epidemiologic studies

The aim of this study was to investigate the association between dietary magnesium and the risk of overall cancer using a meta-analysis. We searched PubMed, SCOPUS, and the Cochrane Review through November 2012. All the articles searched were independently reviewed by 3 authors based on predetermined selection criterion. A total of 13 epidemiologic studies, 6 case-control studies, and 7 prospective cohort studies involving 1,236,004 participants were included in the final analysis. When all studies were pooled, the relative risk (RR) of overall cancer for the highest level of dietary magnesium intake was 0.801 [95% confidence interval (CI): 0.664-0.966) compared with the lowest level of dietary magnesium intake. In subgroup meta-analyses by study design, there was a significant inverse association between dietary magnesium and the risk of cancer in case-control studies (RR = 0.663, 95% CI: 0.475-0.925), whereas there was no significant association in prospective cohort studies (RR = 0.888, 95% CI: 0.745-1.060). Furthermore, there was a significant preventive effect of dietary magnesium for colorectal cancer (RR = 0.775, 95% CI: 0.655-0.919), but not for other cancer. Our meta-analysis showed that higher dietary magnesium intake seems to have a protective effect for cancer, especially colorectal cancer and in females.