Overactive Thyroid linked to Breast Cancer

Women who have an overactive thyroid gland might be at greater risk for breast cancer, a new study suggests.
A team of Danish researchers found that women with the condition, called hyperthyroidism, appeared to face an 11 percent increase in their risk for breast cancer, compared to women with a normal-functioning thyroid gland.
On the other hand, women with the opposite problem, a condition called hypothyroidism, where abnormally low levels of thyroid hormones are produced, saw their risk for breast cancer dip 6 percent below that of women with normal thyroids.The findings stem from a 36-year review that identified nearly 80,000 Danish women with an overactive thyroid and more than 61,000 women with an underactive thyroid. All of the women were cancer-free when they entered the study, which ran from 1978 to 2013.