The thyroid gland controls your metabolism — essentially the speed at which your body burns energy. When it's underactive (hypothyroidism), every metabolic process slows: heart rate, digestion, energy production, and calorie burning.
Women are 5–8 times more likely to have thyroid disease than men. It's one of the most commonly missed reasons why women struggle to lose weight despite appropriate diet and exercise.
Signs Your Thyroid May Be Affecting Weight
- Weight gain without changes in diet or activity
- Inability to lose weight despite consistent effort
- Chronic fatigue and low energy
- Feeling cold all the time
- Hair thinning (especially outer third of eyebrows)
- Constipation and slow digestion
- Brain fog and difficulty concentrating
- Depression or persistently low mood
If you have multiple symptoms, ask your doctor to check TSH, free T3, and free T4. TSH alone is often insufficient to detect subclinical hypothyroidism.
Nutrients That Support Thyroid Function
Iodine
Thyroid hormones are made from iodine. Good sources: iodized salt, seafood, dairy. Don't over-supplement — excess iodine can also impair thyroid function.
Selenium
Essential for converting T4 (inactive) to T3 (active). Best source: 1–2 Brazil nuts daily provides the full daily requirement. Also in fish, poultry, and eggs.
Zinc
Supports thyroid hormone production. Found in oysters, beef, pumpkin seeds, and chickpeas.
Iron
Iron deficiency impairs thyroid peroxidase (needed for hormone synthesis). Particularly relevant for premenopausal women with heavy periods.
Foods to Be Aware Of
Raw goitrogenic vegetables: Raw cruciferous vegetables (broccoli, kale, cabbage) contain compounds that can interfere with thyroid function. Cooking deactivates most goitrogens — cook your cruciferous vegetables and don't worry about it in reasonable amounts.
Gluten for Hashimoto's: Hashimoto's thyroiditis (most common cause of hypothyroidism) is autoimmune. Some evidence suggests gluten-free diets may reduce thyroid antibody levels. Discuss with your endocrinologist.
