Unexplained weight gain can be frustrating and concerning. There are many potential causes, both medical and lifestyle-related. Key factors include changes in metabolism, hormone imbalance, certain medications, and other health conditions. Lifestyle habits like diet, exercise, sleep, and stress levels also play a major role.
Metabolism slows down naturally with age, usually by 2-4% per decade after age 30. This makes weight control harder. Some health issues like thyroid disorders directly impact metabolism as well. An underactive thyroid (hypothyroidism) is a common cause of unexplained weight gain.
Hormones like cortisol, insulin, leptin, and estrogen "control" metabolism and hunger signals. Cortisol is released with stress. High cortisol causes fat storage around the midsection. Insulin manages blood sugar and helps convert carbs into energy or fat. People with insulin resistance tend to gain fat especially around the belly.
Some medications also increase appetite, cause fluid retention, or slow metabolism - such as steroids, antidepressants, seizure meds, diabetes medication, beta blockers for blood pressure, and antipsychotic drugs.
Other potential medical causes include chronic inflammation, food intolerances, sleep apnea, PCOS, Cushing's disease, chronic stress, and digestive issues. Inflammation disrupts normal metabolic function. Food reactions cause gut inflammation for some people. Sleep apnea and poor sleep decrease leptin and increase ghrelin hormones, stimulating appetite. PCOS involves elevated testosterone, insulin resistance, and problems regulating blood sugar.
"I struggled with unexplained weight gain for years before finally getting to the root cause. Proper testing revealed I had low thyroid hormones and high cortisol. With the right treatment plan from Balance Hormone Clinic, I lost 25 pounds and feel so much better!"