Does eating too much soy cause thyroid disease?

Soybeans are a popular food, used to prepare familiar dishes such as tofu, soy milk, and tofu. Beans are rich in protein, vitamins, minerals, fiber, and heart-healthy unsaturated fats.

The isoflavone compound is a type of phytoestrogen in soybeans with a chemical structure similar to the hormone estrogen, helping to reduce hot flashes and night sweats in postmenopausal women, lower blood pressure, and is good for bones.

Many people believe that soy affects thyroid function, causing goiter. However, there is no research confirming that soy causes thyroid tumors or thyroid disease. But soy can change thyroid function in people with iodine deficiency. Specifically, substances in soybeans can inhibit thyroid hormone production, hinder the thyroid gland’s absorption of iodine, and stimulate the pituitary gland to secrete more TSH (thyroid stimulating hormone). If TSH levels increase too much, it can cause the thyroid gland to enlarge, forming a goiter (called a simple goiter).

If you do not have thyroid disease or are not iodine deficient, you can safely eat soybeans and dishes made from these beans in moderation. People with thyroid diseases such as hypothyroidism should limit the use of soy and ensure adequate iodine supplementation in the diet. The safe amount of soybeans for people with thyroid disease is 30 grams a day.

You also need to pay attention to nutritional balance and eat a variety of foods. A balanced diet with enough iodine, protein and nutrients helps maintain thyroid health. Limit the use of processed foods containing preservatives, sugar, alcoholic beverages and caffeine because they can interfere with thyroid hormone absorption. At the same time, you should have regular health checks to detect early signs of thyroid abnormalities and receive timely treatment.