Understanding the role of the thyroid
The thyroid is a small, butterfly-shaped gland located at the base of the neck. Although discreet, it plays a fundamental role in our body: it regulates metabolism, body temperature, digestion, mood, and even fertility.
It primarily produces three hormones:
- T3 (triiodothyronine) and T4 (thyroxine), essential for converting nutrients into energy and ensuring proper cellular function.
- Calcitonin, involved in calcium regulation and bone health.
The production of these hormones is controlled by the pituitary gland, located in the brain, via the hormone TSH (Thyroid Stimulating Hormone). When the thyroid does not produce enough hormones, the pituitary gland secretes more TSH to stimulate its activity. Conversely, if it produces too many hormones, TSH secretion decreases.
A thyroid imbalance can have significant health consequences.
Hypothyroidism: when the thyroid slows down
Hypothyroidism occurs when the thyroid gland does not produce enough hormones, leading to a general slowing down of metabolism. The most common causes include:
- Hashimoto’s thyroiditis, an autoimmune disease where the immune system attacks the gland.
- Iodine deficiencies, a crucial element for thyroid hormone production.
- Certain medical treatments, such as thyroid removal or radioactive iodine therapy.
Symptoms of hypothyroidism include persistent fatigue, unexplained weight gain, excessive sensitivity to cold, dry skin, hair loss, slowed heart rate, and mood disorders. This condition can be exacerbated by stress, and genetics also play a role in its development.
Nutrition: a key factor in supporting the thyroid
While medications like levothyroxine (synthetic T4) are generally prescribed to compensate for hormonal deficiency, diet plays a crucial role in thyroid regulation. An appropriate diet can:
- Provide essential nutrients for the production and conversion of thyroid hormones.
- Promote the conversion of T4 into T3, the active form of the hormone.
- Reduce inflammation and improve gut health, which is linked to proper thyroid function.
Essential nutrients for the thyroid
1. Iodine: essential for hormone production
Iodine is a key component of thyroid hormones. A deficiency can lead to hypothyroidism, while an excess can disrupt the gland, especially in cases of autoimmune diseases.
Iodine-rich food sources:
- Seaweed (nori, wakame, kombu)
- Fish and seafood
- Eggs
- Dairy products
2. Selenium: a protector against oxidative stress
Selenium is essential for converting T4 into T3 and protects the thyroid from damage caused by free radicals.
Where to find it?
- Brazil nuts (1 to 2 per day is sufficient)
- Fish (tuna, sardines)
- Eggs
- Mushrooms
3. Zinc: a key player in hormone absorption
Zinc contributes to the production and activation of thyroid hormones.
Zinc-rich foods:
- Meat and seafood
- Pumpkin seeds
- Legumes (chickpeas, lentils)
4. Iron: essential for oxygenating the thyroid
Iron deficiency disrupts hormone production and can worsen hypothyroidism.
Iron-rich foods:
- Red meat (to be consumed in moderation)
- Legumes
- Spinach
5. Omega-3 fatty acids: reducing inflammation
Omega-3s improve thyroid function by reducing inflammation and promoting better hormone absorption.
Sources of omega-3s:
- Fatty fish (salmon, sardines, mackerel)
- Flaxseeds and chia seeds
- Walnuts
6. Tyrosine
Tyrosine is an amino acid found in proteins. While the body can produce it from other amino acids, it is often necessary to obtain it through diet.
Tyrosine-rich foods:
- Eggs and poultry
- Dairy products
- Almonds
- Avocado
- Pumpkin seeds
7. B vitamins, especially B12
People with hypothyroidism often suffer from a vitamin B12 deficiency, which can worsen fatigue and neurological symptoms.
Where to find it?
- Animal products (organ meats, meat, eggs, fish)
- Brewer’s yeast
Which foods to avoid to protect the thyroid?
1. Excessive goitrogens
Certain foods, known as goitrogens, can interfere with iodine absorption and slow down hormone production if consumed in large quantities.
Foods to limit, especially raw:
- Cruciferous vegetables (broccoli, cauliflower, kale)
- Soy and soy products (tofu, soy milk)
Good to know: Cooking reduces their goitrogenic effect.
2. Gluten in cases of autoimmune disease
For individuals with Hashimoto’s thyroiditis, gluten can worsen inflammation and exacerbate symptoms. Avoiding gluten has been shown to improve health in many cases.
3. Dairy products
Reducing dairy consumption often helps lower TSH levels. There is no need to eliminate it entirely, but moderation is key. Focus on beneficial dairy sources like yogurt, kefir, and small amounts of butter.
4. Sugar and ultra-processed foods
Excess sugar and food additives disrupt hormonal regulation and increase inflammation. Fortunately, there are many healthy alternatives available today to enjoy treats while moderating sugar intake.
Example of a balanced thyroid-friendly meal plan
Breakfast: Spinach omelet, whole grain bread, almond butter
Lunch: Grilled salmon, sweet potato, salad with flaxseeds
Snack: Plain yogurt, Brazil nuts
Dinner: Nori seaweed chips as an appetizer, lentil soup, roasted vegetables with olive oil
Want to learn more?
Check out our latest episode of Kazitalk: Understanding and balancing your thyroid naturally
Persistent fatigue, mood swings, unexplained weight gain… Could your thyroid be the culprit? This small gland plays a crucial role in metabolism, yet its dysfunctions are increasingly common and often go undiagnosed.
In this new episode of Kazitalk, Emna welcomes Isabelle Doumenc, a thyroid specialist, to discuss:
Signs of thyroid imbalances and why they often go unnoticed
Key factors disrupting thyroid function: diet, stress, nutrient deficiencies…
Natural solutions to support thyroid health and restore long-term balance
An essential episode to understand your body and take action daily!
Listen now on Kazitalk.
Conclusion
The thyroid plays a central role in maintaining overall health, and its dysfunction can significantly impact well-being. While medical treatments remain essential for diagnosed conditions, nutrition is a powerful tool to support thyroid function, prevent deficiencies, and ease symptoms.
A diet rich in iodine, selenium, zinc, omega-3s, and B vitamins enhances hormone production and conversion. Conversely, limiting goitrogens, gluten (in autoimmune cases), and ultra-processed foods helps maintain optimal hormonal balance.
Beyond diet, a holistic approach involving quality sleep, stress management, and regular physical activity is crucial. Combined with proper nutrition, these habits help naturally support thyroid health and improve overall well-being. If you suspect a thyroid issue, consult a healthcare professional for accurate diagnosis and tailored guidance.
FAQ: everything you need to know about diet and thyroid health
1. Can diet prevent thyroid disorders?
Diet alone cannot prevent all thyroid conditions, but it plays a crucial role in management and prevention.
2. What are the signs of iodine deficiency?
Fatigue, weight gain, cognitive issues, and goiter.
3. Are supplements necessary?
A balanced diet should provide all essential nutrients, but in cases of confirmed deficiencies, supplements can be beneficial.
4. Should soy be avoided?
Excessive consumption can interfere with iodine absorption, so moderation is advised.
5. Does coffee affect thyroid function?
Yes, coffee can interfere with thyroid medication absorption.
6. Should gluten be eliminated?
Only if an autoimmune thyroid disorder has been diagnosed.
7. Are seaweeds recommended?
They are rich in iodine, so moderation is key.
8. What foods support hypothyroidism?
Fatty fish, eggs, Brazil nuts, leafy greens, and omega-3-rich foods.
9. Are fiber-rich foods important?
Yes, they help regulate digestion, often slowed down in hypothyroidism.
10. Does stress affect the thyroid?
Yes, chronic stress can disrupt hormone production and worsen symptoms.
Taking care of your thyroid starts with a balanced and mindful diet!
