thyroid and heart failure :: Article Creator 5 Thyroid Myths Doctors Say To Stop Believing Now It's true that this butterfly-shaped gland in your neck keeps your metabolism on course, but it is not to blame every time things go south. Experts share thyroid myths to stop believing now. 1. Myth: If you have unexplained weight gain and fatigue, it's most likely a thyroid problem. Mythbuster: While these symptoms can point to a thyroid issue, "weight gain and fatigue can result from other factors such as diet, lifestyle, stress, and poor sleep," says Mihail Zilbermint, M.D., M.B.A., an associate professor of medicine at Johns Hopkins University School of Medicine. The thyroid releases hormones that help regulate many bodily functions, and when it puts out too much of them, that's known as hyperthyroidism. When it secretes too little (hypothyroidism), you may gain weight and feel fatigued. Ask your doctor for a thorough evaluatio...