Brazil Nuts Support Thyroid

Can brazil nuts support your thyroid? 

Many articles sensationalise the effect of specific super foods on health conditions, and while this article focuses on the health benefits of the mineral selenium, found in abundance in brazil nuts, we have to consider the evidence as part of the bigger picture.

This question brings me back to a time when my father’s friend told him that eating five almonds everyday would help reduce his raised cholesterol levels. My father, who probably had never knowingly eaten an almond in his 70 years, spent five painstaking minutes to eat five almonds daily, followed by his white bread ham sandwich and slice of jam roll. Unsurprisingly, after a couple of weeks, his cholesterol levels remained the same!

Researchers tend to study nutrients, foods and supplements in isolation and many studies have looked at the effect that selenium has in supporting thyroid health. This article looks at some of this research.

The active thyroid hormone is called triiodothyronine (T3), this is converted from the inactive hormone, Thyroxine (T4), by removing iodine atoms. One of enzyme that catalyzes this reaction is called deiodinase enzyme 1 and is selenium dependent. (1) A double-blind study showed that elderly subjects supplementing, showed a significant decrease in T4 levels compared to the placebo group, suggesting there was an increase in peripheral conversion of T4 to T3. (2) In 2018, a study found that selenium deficient children had high levels of free T4 which were reduced once supplemented with selenium. (3)

There is also evidence to show the beneficial effects that selenium may have in supporting those diagnosed with autoimmune thyroiditis disease (AITD). A study (4) found that female patients, with AITD, when supplemented with 200ug/day had suppressed serum levels of thyroid peroxide antibodies. Another study completed in Bavaria, Germany – an area with known selenium deficiency - supplemented subjects with AITD with 200ug. After a 90 day period, 9 out 36 patients (25%) showed anti-TPO levels that were completely normalized. (5)

Selenium seems to modify and may improve the inflammatory activity and immune response in those with AITD.

Here we have studies which show the importance for having adequate selenium levels in the body for those with thyroid health issues, firstly for the conversion of the thyroid hormones and secondly for modulating the immune system in those with auto immune conditions. For some, particularly those with selenium deficiency, supplementing with selenium or consuming foods rich in selenium such as brazil nuts may indeed result in improvements in symptoms.

At TNI we understand the importance of a personalized program and where selenium may be a key concern for you we also consider many other factors which could be contributing to your overall health.

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