Your thyroid is a small gland that controls how fast your body works and how your heart beats. When your thyroid doesn’t work properly, it can affect your heart health. Scientists reviewed research about how certain nutrients—like selenium, iodine, and zinc—might help people with thyroid problems, especially a condition called Hashimoto’s thyroiditis. They also looked at how eating a Mediterranean diet (lots of vegetables, fish, and olive oil) might protect your heart. The review suggests that getting the right mix of these nutrients could be important for people with thyroid disease, but more research is needed to understand exactly how they work together.

The Quick Take

  • What they studied: How specific nutrients and eating patterns affect thyroid disease and heart health, especially in people with Hashimoto’s thyroiditis (an autoimmune thyroid condition)
  • Who participated: This was a review of existing research, not a new study with participants. Scientists looked at many previous studies to understand what we know about nutrients and thyroid health
  • Key finding: Certain nutrients—selenium, iodine, and zinc—appear to help reduce inflammation and support thyroid function, which may lower heart disease risk in people with autoimmune thyroid disorders
  • What it means for you: If you have thyroid problems, paying attention to these specific nutrients and eating patterns like the Mediterranean diet may help protect your heart health. However, talk to your doctor before making major dietary changes, as individual needs vary

The Research Details

This is a review article, which means scientists didn’t conduct a new experiment. Instead, they carefully read and analyzed many existing studies about how nutrients affect thyroid disease and heart health. They looked at research on three main nutrients—selenium, iodine, and zinc—and how the Mediterranean diet might help people with thyroid problems.

The researchers also introduced new ideas about how these nutrients might work differently in men versus women, and how they might help calm down the immune system when it attacks the thyroid. This type of review is helpful because it brings together information from many studies to see the bigger picture of what we know.

Understanding how nutrients work together is important because people with thyroid disease often have higher risk of heart problems. By reviewing all the available research, scientists can identify patterns and create better recommendations for what people should eat. This approach also helps identify gaps in our knowledge where more research is needed.

This is a review article, which means it summarizes existing research rather than testing something new. The strength of the conclusions depends on the quality of the studies reviewed. The authors introduced new frameworks and ideas, which is valuable for future research but means some suggestions are based on emerging evidence rather than proven facts. Readers should understand that review articles are helpful for understanding current knowledge but may not be as definitive as large-scale studies testing specific treatments

What the Results Show

The review found that selenium appears to be particularly important for people with autoimmune thyroid disease. This nutrient helps reduce inflammation in the body and supports the thyroid’s ability to make hormones properly. Iodine is essential because the thyroid needs it to produce thyroid hormones, and without enough iodine, the thyroid can’t work correctly.

Zinc also plays an important role by helping the immune system work properly and reducing excessive inflammation. When the immune system attacks the thyroid (as happens in Hashimoto’s thyroiditis), zinc may help calm this response.

The Mediterranean diet—which includes lots of vegetables, fruits, fish, whole grains, and olive oil—appears to be beneficial because it provides many of these nutrients together and is naturally anti-inflammatory. This eating pattern may be especially helpful for protecting heart health in people with thyroid disease.

The researchers also suggested that men and women might benefit from different amounts of these nutrients, though more research is needed to confirm this idea.

The review highlighted that vitamin D also plays a supporting role in thyroid health and immune function. The combination of multiple nutrients working together appears to be more effective than any single nutrient alone. The researchers noted that how well these nutrients work may depend on factors like genetics, overall diet quality, and individual health status.

Previous research has shown that individual nutrients like selenium and iodine affect thyroid function. This review builds on that knowledge by exploring how these nutrients work together and how they specifically help people with autoimmune thyroid disease. It also introduces new thinking about sex-specific differences and the importance of overall dietary patterns rather than just individual nutrients. The focus on the Mediterranean diet is relatively newer in thyroid research compared to older studies that looked at single nutrients in isolation.

This is a review of existing research, not a new study, so the conclusions are only as strong as the studies reviewed. The researchers introduced new ideas about sex-specific nutrient needs and how nutrients interact, but these ideas need to be tested in actual studies. The review doesn’t provide specific dosage recommendations because the research on optimal amounts is still developing. Individual responses to nutrients vary greatly, so what works for one person may not work the same way for another. More research is needed in people with different backgrounds and health conditions

The Bottom Line

If you have autoimmune thyroid disease, consider working with a doctor or dietitian to ensure you’re getting adequate selenium, iodine, and zinc through food or supplements. The Mediterranean diet appears to be a beneficial eating pattern that naturally provides these nutrients and supports heart health. Start by eating more fish, vegetables, whole grains, and using olive oil. These recommendations are based on moderate evidence—they appear helpful but aren’t yet proven as definitive treatments. Always consult your healthcare provider before starting supplements, especially if you take thyroid medication

People with Hashimoto’s thyroiditis or other autoimmune thyroid conditions should pay special attention to this research, particularly those concerned about heart health. People with subclinical hypothyroidism (mild thyroid dysfunction) may also benefit. This is less relevant for people with normal thyroid function, though the Mediterranean diet is generally healthy for everyone. Pregnant women and those planning pregnancy should discuss nutrient needs with their doctor, as thyroid health is especially important during pregnancy

Changes in thyroid function and inflammation typically take several weeks to months to show up in blood tests. You might notice improvements in energy, mood, or heart symptoms within 4-8 weeks of consistent dietary changes, though some people take longer. Heart health improvements usually take months to years to develop. Be patient and consistent, and work with your doctor to monitor progress through blood tests

Want to Apply This Research?

  • Track daily intake of selenium-rich foods (Brazil nuts, fish, eggs), iodine sources (seafood, seaweed, dairy), and zinc sources (shellfish, legumes, seeds). Aim for at least one serving from each category daily and log weekly compliance
  • Add one Mediterranean diet element per week: Week 1 - switch to olive oil for cooking, Week 2 - eat fish twice weekly, Week 3 - add more vegetables to meals, Week 4 - include whole grains. Use the app to set reminders and track which changes feel sustainable
  • Log thyroid-related symptoms weekly (energy level, mood, temperature sensitivity) on a 1-10 scale. Track dietary adherence to Mediterranean pattern. Schedule quarterly check-ins with your doctor for thyroid blood tests (TSH, free T4) to measure objective progress. Use the app to share symptom trends with your healthcare provider

This review summarizes research about nutrients and thyroid health but is not medical advice. Thyroid disease requires professional medical care and monitoring. Do not start, stop, or change thyroid medications or supplements without consulting your doctor, as improper treatment can affect heart health and other body systems. Individual nutrient needs vary based on age, sex, health status, and medications. If you have thyroid disease, work with your healthcare provider or a registered dietitian to develop a personalized nutrition plan. This information is educational and should not replace professional medical evaluation and treatment.