You’re celebrating your 50th birthday and you step over to the closet to pick out a skirt and blouse for the occasion. And you’re surprised to find that somehow the waistband of the skirt you wore last summer is a tad too tight. You may be experiencing middle age weight gain with a few extra pounds suddenly padding your waistline. Is menopause the culprit? Are the years catching up with you? Why is this happening and is it unavoidable or are there steps you can take to preserve you former figure?

Many women in their late 40s and mid 50s experience a noticeable thickening in their mid-section, as their once pear-shaped figures transform into apple shapes. Weight which previously ended up on the hips and thighs was now settling around the abdomen. And, this shape shifting can occur even if you don’t gain a pound.

Unfortunately, there is more bad news. The type of fat that collects around the belly and abdomen makes women more prone to diabetes, high blood pressure, high cholesterol, heart disease, stroke and certain types of cancer. Women who gain in excess of 20 lbs after menopause increase their breast cancer risk by nearly 20%. At the same time, women who lose weight after menopause may significantly reduce their risk.

There are multiple factors at work that can contribute to midlife weight gain. But, the good news is there are things you can do to maintain or even lose weight.

Factor #1: Our metabolism slows due to muscle loss.

Our calorie needs decrease as we age. One reason for this is that our muscle mass tends to decrease especially if our exercise habits start to deteriorate. Since muscle burns more calories than fat, if we have less muscle mass, then we burn fewer calories. So, if we continue to eat the same amount of calories as we have in the past, those now excess calories will be stored up as body fat. This is what we typically refer to as a slowdown in our metabolism.

Also, as the estrogen in a woman’s body lessens, her metabolism begins to further slow down. This happens at a rate of about 5% every ten years. If you were able to consume 2400 calories a day when you were 30 and not gain a pound, by the time you are 50 your daily calorie intake should drop down closer to 2100 to avoid weight gain.

To Avoid Weight Gain: Consume 250 fewer calories daily.

This might mean giving up dessert or not stopping for that iced coffee drink. Don’t rapidly or drastically cut your calorie intake, as your body will respond by conserving energy and your metabolism will further slow down. Cut calories gradually. Be sure to eat fewer high-fat foods and opt for more nutritionally dense, fiber-rich foods like fruit, vegetables, beans and whole grains as well as fish and low-fat dairy. Also, another way to keep your metabolism speeding along is to eat 6 times daily. That’s right. Eating a healthy snack in between your meals can keep your metabolism humming along and can help prevent overeating at main meals. Also, drink plenty of water. You’ll feel full and the water helps to flush out fat.

Factor #2: We’re stressed out (and overeating).

The hard truth is that many of us are eating more than we used to. Why? Maybe it’s stress. The ups and downs that can be common in menopause can cause more erratic eating behavior and cravings for high-fat, comfort foods. The fact that you may be dealing with teenage angst at home, a divorce, a career change or other mid-life problems may be adding to the stress. Plus, when our estrogen levels are normal, they act to suppress the appetite. During menopause, the declining estrogen can actually whet a woman’s appetite.

Stress also releases the hormone Cortisol and elevated levels of Cortisol can contribute to abdominal weight gain along with elevated glucose and insulin levels.

To Avoid Weight Gain: Relax with healthy stress reduction.

Don’t fall into bad habits just because you’re tense. Learn to relax and to deal with stress in healthy ways, such as working out at the gym.

Factor #3: We’re exercising less.

Inactivity contributes to loss of muscle mass. So, at the same time that you may be losing a half pound of muscle each year, you may find that you’re gaining one-and-a-half pounds of fat. It’s important not to let the occasional aches and pains that we all start to feel keep us from getting our daily dose of exercise.

To Avoid Weight Gain: Stay active.

Combine aerobic exercise and activities like walking, hiking and biking, which keep you feeling younger, stronger and more alive, with a weight training regimen. The latter will help build lean muscle mass which in turn will help burn more calories. The aerobic exercise will get your heart pumping and help boost your metabolism. Set as your goal 30 minutes of activity each day or do 10-minute bursts of exercise several times a day.

The added benefits of exercise include: increased production of HDL (the good fat) which reduces LDL, lower risk of diabetes and less risk of osteoporosis.

Factor #4: Calcium and vitamin D deficiencies.

Recent research studies show that among women who were deficient in calcium and vitamin D, supplementation with 1000 mg calcium and 400 IU of vitamin D made them 11% less likely to gain weight. Plus, there was the added benefit of slowing bone loss and lowering the risk of fracture from osteoporosis.

To Avoid Weight Gain: Take calcium and vitamin D.

Yes, your body shape may still change as you get older, and those old jeans may no longer fit right, but if you increase your physical activity with a combination of strength training and aerobic exercise, reduce the number of calories you consume daily, relax and watch the types of foods you eat, you’ll be doing a lot to maintain your health and vitality for years to come.