While weight gain can most often be attributed to eating more calories than you are expending, there can also be some kind of hormonal imbalance at play. Recently a reader asked if thyroid problems can cause weight gain, and while the short answer is yes I have done a bit of research to provide a little more information on a rather complicated system (human biology is pretty amazing!!!).
Hormones produced by the thyroid influence how quickly or slowly you burn energy, aka your metabolism. If you don't produce enough hormones you have what is known as hypothyroidism and your metabolism slows way down. This condition can also cause lethargy, reduced appetite and brittle nails. While hypothyroidism is rarely the only culprit in weight gain it can be a contributing factor.
Having your thyroid hormone levels checked is relatively easy and merely requires a blood test - and you don't even need to fast before having your blood drawn. The test measures the thyroid stimulating hormone (TSH) levels in your blood. If the level is above 5 IU/liter, your body is trying to stimulate an under-performing thyroid.
If you think you are experiencing thyroid problems make an appointment to discuss the issue with your primary care physician.