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Breast cancer is the most commonly diagnosed cancer among women in the United States, and thyroid disease affects millions of American women. Most breast cancers are sensitive to hormones such as estrogen, and researchers believe that thyroid hormones have estrogen-like effects. So for years, scientists have wondered whether excess thyroid hormone contributes to breast cancer. According to new research, the answer may be yes.
It’s all about the thyroid gland
The thyroid gland is a butterfly-shaped gland located at the base of the neck that produces thyroid hormones. Thyroid hormones affect almost every cell in the body and play many important roles, including controlling metabolism, heart rate, and body temperature.
Some people have hyperthyroidism, or an overactive thyroid, in which the thyroid gland produces too much thyroid hormone. This can lead to weight loss, thinning hair, sweating, anxiety, and palpitations. Women’s thyroid function is 5-10 times higher than men’s.