Sleeping itself does not necessarily cause weight gain. I would be more concerned to determine whether the same problem that is causing you to sleep more is also causing you to gain weight. I strongly suggest that you go see your doctors
">primary care doctor about this issue as soon as possible.
As one example of what may be going on, an under active thyroid gland can cause hypothyroidism, which will lead to fatigue (increased sleep) and weight gain, in addition to other symptoms, such as feeling cold, changes in the skin and hair, and low mood. Hypothyroidism can easily be diagnosed with a simple blood test drawn in your doctor's office.
is a very common cause of increased sleepiness and fatigue, couple with weight gain. Other symptoms might include tears, sadness, loss of interest in sex or hobbies, and the like.
Start by setting up an appointment with your doctor as soon as possible. They will perform a complete examination and screen you for hypothyroidism and depression, as well as considering other possibilities. Based on what they discover, they will be able to recommend a treatment to get you feeling better and sleeping more normally.