Tofu is a nutritious food, providing plant protein, isoflavones, calcium and many important minerals. However, when consumed excessively, tofu can cause negative effects on health, especially on hormones, digestion, thyroid and mineral absorption.
Tofu contains isoflavones, a compound with a structure similar to the hormone estrogen, according to Dr. Mark Messina, a nutritionist and executive director of the American Soy Research Association. When eaten too much, men can experience decreased testosterone, leading to reduced appetite, fatigue, decreased muscle mass and affecting physiology.
In women, isoflavones can affect the menstrual cycle, especially for those with high estrogen or are taking hormone replacement therapy. Tofu can cause menstrual disorders and upset female hormone balance.
In addition to affecting hormones, tofu can also cause digestive problems. Plant protein in tofu is quite difficult to digest, especially for people with weak digestive systems or intestinal diseases.
Doctor David L. Katz - preventive medicine expert at Yale University (USA) - said that eating too many tofu can cause bloating, flatulence, and indigestion because the digestive system cannot absorb all the vegetable protein in a short time. Tofu is also rich in phytic acid, a compound that can combine with iron, zinc, and calcium in the intestines, reducing the ability to absorb these important minerals.
In addition, tofu also contains goitrogen, a compound that can interfere with iodine absorption, thereby affecting thyroid function. People who eat a lot of tofu but do not supplement enough iodine from iodized salt or seafood can have hypothyroidism, causing fatigue, weight gain and hair loss. A diet high in tofu can reduce thyroid hormone production, especially in people with a history of thyroid disorders or iodine deficiency.
Given the possible negative impacts, international experts recommend eating tofu in moderation to avoid affecting health, each person should only consume about 100 - 200g of tofu/day to ensure nutritional balance. In particular, people with thyroid disorders or anemia should limit eating too many tofu, while supplementing enough iodine, iron and calcium from other foods such as seafood, red meat and green vegetables.
When processing, it is also necessary to combine tofu with foods rich in vitamin C such as oranges, bell peppers and tomatoes to increase iron absorption and reduce the negative effects of phytic acid.
