Five Surprising Reasons You're Gaining Weight

4. You May Be Gaining Weight Because of a Medical Condition
The most common medical condition that causes weight gain is hypothyroidism. A deficiency of thyroid hormone can decrease metabolism, causing appetite loss and weight gain.

"If you are feeling fatigued, lethargic, swelling, hoarse voice, intolerance to cold, sleeping too much or headaches, you should see your doctor for an easy test to determine if you have hypothyroidism.

Much rarer is a condition known as Cushing's syndrome—a disorder caused by
an excess of the hormone cortisol—that can also result in weight gain.

5. You May Be Gaining Weight Because of Menopause
Women reach menopause at a range of ages, but most are in midlife and are often less physically active than when they were younger. Along with aging comes a natural slowing of metabolism. At the same time, hormonal changes can trigger hunger, depression, and poor sleep.

"It is multifactoral. When women go through menopause, they lose estrogen, causing their shapes to change—usually a loss of hip and thigh weight. And they start to gain more in the middle. She explains that estrogen favors fat deposition in the lower body, and when you lose this hormone, fat is more likely to be deposited in the midsection (much like men). This spare tire around the middle has been not so affectionately called the "menopot.

"The key to avoiding this extra belly fat is to maintain and increase the amount of lean body mass, which will, in turn, increase your metabolism or calorie burn rate."Women need to understand how critically important weight lifting and strength training is to their health. And don't worry, doing strength training won't make women muscle-bound, experts say.

Exercise also helps offset bone loss that can come with menopause. A combination of exercise and a healthy, calorie-controlled diet rich in calcium and vitamin D is the answer to thwarting menopausal weight gain.