Is this realistic? Of course it is! With a combination of a few life adjustments, maintaining a healthy body, regulated metabolism, vitality and energy is certainly attainable. While society tends to blame simply what you eat to blame for post-fifty unwanted weight gain or an energy “sucker,” it comes down to what it’s always been; intake in versus intake out. Your body still requires a balance of a healthy diet and sufficient exercise, not only to prevent weight gain but to maintain flexibility and ward off unwanted ailments further down the road.

Dr. Robert Butler, a gerontologist and geriatric psychiatrist; founder and president of the International Longevity Center and author of “Why Survive? Being Old in America” contributed to a wonderful article written for CBS. “As you get older, there is a tendency to become less active. As a result, you lose muscle mass and the metabolism slows down, he explains. But if you remain active and maintain your muscle mass, your metabolism will not slow down much. What does change are dietary needs as people age, he says. So if you are a postmenopausal woman, or a man over 50, Dr. Butler suggests cutting back on iron supplements. Iron can be dangerous because it accumulates in the heart and causes heart trouble.

So he suggests in addition to having discipline, aim to eat 5-7 servings of fruits and vegetables, lots of fiber to avoid any bowel problems. Obviously the body will undergo physical changes like skin elasticity, a decrease in muscle mass if you become inactive. But if we stay fit and exercise body and mind, Dr. Butler says we are certainly able to stay in shape.

Here are four components to keeping the weight off after 50 from Dr. Butler, courtesy of www.CBSnews.com:

Aerobics: You should engage in real physical activity where you are sweating at least three times a week.

Muscle Strengthening: Building strong muscles will keep your metabolism up (muscles burn more calories than fat) and help support your skeleton, keep your bones/back aligned properly. Also helps keep your body balanced (see 4).

Stretching/ Flexibility:If you don't stretch your muscles, your body can become tight and rigid, making it more painful and difficult to do ordinary activities like putting on shoes and reaching for things on shelves. You can increase your flexibility by doing a series of stretches a few times a week. When you get up, you should do a few stretches, like lie on the floor and reach as far as you can in all directions, move your legs from side to side, do the mad cat position (arch your back), put your hands on the side of the doors and lean into the opening. You can also do those typical runner's stretches like stretching your hamstring and quadriceps. You should hold each stretch for at least 30 seconds; don't rock back and forth.

Balance: It is important to do balance-building exercises so that you can react to situations and not fall and break a hip. You can do balance building exercises during the routine course of your day: stand on one leg while you are waiting in line, or go up and down on your toes.

Exercise your brain by doing acrostics, crossword puzzles, or studying a language.

There are some sports that are better for you than others as you age, says Dr. Butler. For example, it's better to be a fast walker than a runner as you age (after 50) because you do less damage to your knees and ankles. A good fast walk can give you the same health advantages, he says.

Swimming gives you a good low-impact aerobic workout, but it doesn't build bone density because your feet are not hitting the ground. You need gravity fighting activity to build bone density. The pull of gravity helps the bones build density, and it is important to have dense bones as you age so that you don't get osteoporosis, or bone thinning, which is a particular problem for women as they age. About 15 percent of the osteoporosis cases are also men; 85 percent of osteoporosis cases are women because women have lighter bones to begin, Dr. Butler says.

“The good news is that even if a person has had a sedentary life, it is never too late to exercise. Gradually, a person can get back in shape.”