Brazil Nuts for Thyroid Health

Preliminary evidence 4 studies

Research suggests that Brazil nuts, as a naturally rich source of organic selenium, may offer some benefits for thyroid-related health markers, particularly by supporting selenium status and antioxidant activity, with one randomized controlled trial noting that Brazil nut flour consumption was associated with stable free T3 levels compared to a decline in the placebo group. A 2022 systematic review of 24 clinical studies found consistent improvements in selenium levels and antioxidant markers across various populations, with hemodialysis patients showing improvements in thyroid function specifically, though the authors noted that most included studies were non-randomized, limiting the strength of conclusions. Studies also indicate that Brazil nuts may be relevant for thyroid cancer patients on low-iodine diets as an iodine-free source of organic selenium, though this observation comes from a letter to a journal editor rather than a controlled trial. Findings are mixed overall, as a 2018 review raised substantive concerns about the risks associated with Brazil nut consumption, including selenium toxicity from overconsumption, potential aflatoxin contamination, allergic reactions, and a possible association between high selenium intake and type 2 diabetes, underscoring that the unusually high selenium content of these nuts means the margin between benefit and risk warrants careful consideration.

Related studies

Citations from PubMed and preprint sources. Match score (0-100) reflects automated search ranking, not clinical appraisal.

Title Type Year Direction Match
Commentary: Health Concerns of Brazil Nut Consumption. Other 2018 Mixed 72
Effects of Regular Brazil Nut (Bertholletia excelsa H.B.K.) Consumption on He... Review 2022 Supports 67
Differentiated thyroid cancer and selenium supplements for protection of sali... Other 2018 Supports 62
Intake of partially defatted Brazil nut flour reduces serum cholesterol in hy... RCT 2015 Supports 57

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Medical Disclaimer: Noyemi provides information from published research for educational purposes only. This content is not medical advice and does not replace consultation with a qualified healthcare provider. Always consult your doctor before starting, stopping, or changing any supplement regimen, especially if you take medications or have existing health conditions.