A sluggish thyroid
Your thyroid gland makes hormones that regulate the way your body uses energy. An underactive thyroid (hypothyroidism) disrupts your metabolism, as well as many other aspects of your health. Some estimate that as many as 10 percent of adults have hypothyroidism, which is more common in women and is most often diagnosed in the 40s and 50s.
Could this be you? Besides weight gain or an inability to lose weight, you may notice fatigue, hair loss, dry skin, joint pain and muscle weakness, heavy periods, increased sensitivity to cold, even depression. Many people with low-grade hypothyroidism just feel off, with no obvious signs of being truly sick.
How to get tested: Ask your internist to run a TSH (thyroid-stimulating hormone) screening. In general, the higher your TSH level, the slower your thyroid is. While traditional normal' values are between .45 and 4.5, if your level is above 2, you might still struggle to lose weight, explains Jamie Kane, MD, medical director of Park Avenue Medical Weight and Wellness in New York City. Your doctor may also want to check your levels of T-3 and T-4, the two main thyroid hormones. But hypothyroidism isn't always a straight numbers game; more and more doctors are now treating the symptoms, not just the blood-test results. If a patient isn't feeling well, it's often because her thyroid isn't functioning as well as it should for her body, says Erika Schwartz, MD, an internist in New York City.
How it's treated: Your doc will usually start by prescribing a low-dose T-4 thyroid hormone like Synthroid. If your symptoms don't improve, discuss upping your dosage or switching to a combination of T-3 and T-4.