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"Why am I feeling so lethargic and gaining weight when I haven't changed my diet or routine? "

ZocdocAnswersWhy am I feeling so lethargic and gaining weight when I haven't changed my diet or routine?


I'm a 36 year old woman who has never had an issue maintaining a healthy weight until recently. In the past month, I've been gaining approximately 1-2 pounds a week, and for the past 4-5 months my energy level has dropped drastically. I work as a professional in an office environment, so my day to day schedule does not vary, I exercise regularly and I haven't changed my diet, which is fairly healthy. I'm becoming very concerned at my diminishing energy levels as well as this sudden, unexplained weight gain. My mother and grandmother both had thyroid issues, could this be the cause of my lethargy and weight gain? Can a primary health care provider diagnose this or would I need to see a specialist?


Your weight gain and decreased energy levels in the setting of an unchanged exercise routine and diet could certainly be caused by a thyroid problem (namely hypothyroidism, or underactive thyroid). The fact that both your mother and grandmother have had thyroid issues increases the possibility of you suffering from thyroid disease as well. Associated symptoms of hypothyroidism include depression, depressed ability to think clearly, constipation, abnormalities of the menstrual cycle, coarsening of the hair, brittle nails, and intolerance to cold temperatures, among others. You should certainly see your primary care physician to help determine the cause of your symptoms. While hypothyroidism is a possible diagnosis, there are other etiologies that should be considered (for example, depression), and your doctor can ask more specific questions about your diet and exercise routines, associated symptoms, etc. A thorough physical exam can help point towards hypothyroidism or other causes of your symptoms as well. Lastly, a routine blood test which looks at the level of your Thyroid Stimulating Hormone (TSH) is the first step in determining if your thyroid is functioning appropriately. If you are in fact diagnosed with hypothyroidism, your primary care doctor may elect to treat you or refer you to an endocrinologist for further care.

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