Extra calories may not be the only cause of weight gain.
1. You Might Be Gaining Weight Because of Lack of SleepThe body functions best when well rested. "When you don't get enough sleep, your body experiences physiological stress and, biochemically, you store fat more efficiently," says May.
When you're tired, you also don't handle stress as well, so you may reach for food as a coping mechanism. Further, you may be taking in extra calories from late-night snacking. Some people think eating might help them get back to sleep, but all it really does is add more calories to their daily total.
Symptoms that you may not be getting enough rest include fatigue, low energy levels, nodding off easily, and feeling irritable.
Strive to get eight hours of sleep each night.
"Add about 15 minutes to your bedtime and see how you feel," suggests May. "Continue to experiment with additional 15-minute increments until you find the ... amount of sleep that is right for you."
When you develop good sleeping rituals and get regular exercise, you sleep better, she adds.
2. You May Be Gaining Weight Because of StressWe live in a society that demands we do more, be more, and achieve more. Stress moves us forward and helps cope with life's demands, but it also affects our mood and emotions.
"Stress response, whether it is 'fight-or-flight,' juggling too many responsibilities, or coping with financial pressures, triggers a biochemical process where our bodies go into survival mode," explains May. "Our bodies store fuel, slow down metabolism, and dump out chemicals [cortisol, leptin, and other hormones] which are more likely to cause ... obesity in the abdominal region."
Many people reach for food to help ease the stress. But, of course, this doesn't work in the long run.
"Food is a temporary fix because it does not deal with the real stressors that must be addressed in order to reduce the trigger for eating and fix the problem," says May.
Susan Bowerman, MS, RD, assistant director of the UCLA Center for Human Nutrition, says stress eaters tend to prefer high-carbohydrate foods because these foods trigger an increase in the brain chemical serotonin, which has a calming effect. "It is almost like self-medicating," she says. "Many people binge on starchy foods to make themselves feel better."
Both May and Bowerman recommend relaxation techniques as well as exercise, which also burns calories and provides other health benefits.
3. You May Be Gaining Weight Because of MedicationsSome prescription drugs used to treat depression, mood disorders, seizures, migraines, blood pressure, and diabetes can cause weight gain, from a modest amount to as much as 10 pounds per month. Some steroids, hormone replacement therapy, and even oral contraceptives may also cause gradual weight creep. Your medicine cabinet might be the cause of your weight gain if you've gained 5 or more pounds in a month without a change in your lifestyle.
"Every drug works a little differently to cause weight gain, from increasing appetite, altering the way fat is stored, to how insulin levels change," says May. "And not all drugs have the same side effects on all people."
In the case of antidepressants, weight gain may not even be related to the action of the drug -- feeling better can also result in a heartier appetite. Some drugs can cause fluid retention that shows up on the scale as weight gain, but is not fat, and is usually easily corrected.
Experts say that some of the most common types of medications that may cause weight gain are:
Steroids
Antidepressants
Antipsychotics
Antiseizure medications
Diabetes medications
High blood pressure medications
Heartburn medications
But it's important to remember that a few extra pounds may be well worth the trade-off of what a particular medication does for your overall health, experts say. Further, even if your medications are the cause of your weight gain, you still need to be mindful of eating a healthy diet and getting regular exercise.
"Rarely is the problem solved with a change in meds," says May. "These things can contribute, but rarely are the sole cause of the weight gain."
If you suspect your medication is causing weight gain, talk to your health care provider to see about changing your prescription. But whatever you do, don't go off your medication without seeking medical advice.
"There could be very serious consequences if you stop taking your medication without consulting your physician," says May.
4. You May Be Gaining Weight Because of a Medical ConditionThe 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," says May.
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 MenopauseWomen 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," says Bowerman. 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," says Bowerman. 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.