Sudden weight gain can be alarming, especially if you haven't made any major changes to your diet or exercise routine.
There are a number of possible causes, including:
Certain medical conditions, such as hypothyroidism, Cushing's syndrome, and polycystic ovary syndrome (PCOS), can cause sudden weight gain
Some medications, such as corticosteroids, antidepressants, and antipsychotics, can also lead to weight gain
Fluid retention can cause a temporary increase in weight.
Changes in hormones:
Hormonal changes, such as those that occur during menopause and perimenopause, can also contribute to weight gain
Stress can lead to the production of the hormone cortisol, which can promote weight gain, especially around the midsection
Lack of sleep:
When you don't get enough sleep, your body produces more of the stress hormone cortisol, which can lead to weight gain
Many people gain weight after quitting smoking.