Your thyroid plays a crucial role in regulating your metabolism, energy levels, and overall hormonal balance. However, certain foods can interfere with thyroid function—especially if you’re already dealing with hypothyroidism, Hashimoto’s disease, or other thyroid-related conditions.

In this article, we’ll explore 6 common foods that may negatively impact your thyroid health, and how to adjust your diet for better hormone balance.

1. Soy and Soy-Based Products

Soy contains isoflavones, plant compounds that can disrupt thyroid function by interfering with the body’s ability to absorb iodine and produce thyroid hormones. This is particularly concerning for individuals with iodine deficiency or those taking thyroid hormone replacement.

Tip: If you’re on levothyroxine, avoid consuming soy products within 3–4 hours of taking your medication.

Examples: Soy milk, tofu, tempeh, edamame, miso.

2. Raw Cruciferous Vegetables

While vegetables like kale and broccoli are nutritious, consuming them raw in large amounts can hinder thyroid hormone production. They contain goitrogens, compounds that may reduce iodine absorption—essential for healthy thyroid function.

Tip: Cooking cruciferous vegetables reduces their goitrogenic effects. Steaming or sautéing is recommended.

Examples: Raw cabbage, broccoli, kale, Brussels sprouts.

3. Gluten

For individuals with autoimmune thyroid diseases like Hashimoto’s, gluten can act as a trigger for inflammation and immune system flare-ups. It may also damage the gut lining, affecting nutrient absorption and medication effectiveness.

Tip: Consider a gluten-free diet if you experience persistent fatigue, digestive issues, or have been diagnosed with Hashimoto’s.

Examples: Wheat, barley, rye, processed oats.

4. Refined Sugar

Excess sugar causes inflammation, increases insulin resistance, and can worsen symptoms of hypothyroidism such as weight gain, mood swings, and brain fog.

Tip: Replace refined sugar with natural sweeteners like honey (in moderation) or fruits with a low glycemic index.

Examples: Candy, pastries, sugary drinks, packaged desserts.

5. Processed and High-Sodium Foods

People with underactive thyroids are more prone to high blood pressure and water retention. Processed foods are often loaded with sodium, which can compound these issues and strain the cardiovascular system.

Tip: Read food labels carefully and opt for “low sodium” alternatives whenever possible.

Examples: Instant noodles, canned soups, deli meats, frozen meals.

6. Coffee (Taken Too Soon After Medication)

Drinking coffee too soon after taking thyroid medication can reduce its absorption by up to 60%, diminishing its effectiveness and slowing down recovery.

Tip: Wait at least 30 to 60 minutes after taking levothyroxine before having your morning coffee.

Examples: Espresso, cold brew, cappuccino, instant coffee.

Foods That Support Thyroid Health

To keep your thyroid functioning at its best, include these in your diet:

• Fatty fish (rich in omega-3 and iodine): salmon, sardines, mackerel
• Eggs (good source of selenium and protein)
• Nuts and seeds: pumpkin seeds, Brazil nuts, flaxseeds
• Seaweed (rich in iodine—consume in moderation)
• Antioxidant-rich fruits: blueberries, apples, kiwi

Final Thoughts

Your diet plays a powerful role in supporting (or hindering) your thyroid health. By minimizing these 6 thyroid-disrupting foods and focusing on a nutrient-rich, whole-food approach, you can take a big step toward balanced hormones and better well-being.

If you have thyroid concerns, always consult a healthcare provider before making major dietary changes.