You Are What You Eat: Diet Tips for Every Age

Your complete guide to staying slim and healthy at every age. Plus, try out a virtual body makeover to see how you'd look if you lost or gained weight!

It's no secret that a diet of sweets and fried foods will lead to the dreaded muffin top. But what should you eat to keep trim and strong? What works for women in their 20s will not necessarily work for women in their 40s, 50s, and beyond. Here, how to be healthy in each decade.

In Your 20s

"Your body is in build-up mode," says Ashley Koff, a dietician in Los Angeles. "Having a balanced eating routine will improve your weight and health."

Let go of your college ways. Still eating your first meal at 3:00 p.m.? Not a good idea if you're trying to lose weight. "Eating every three to four hours will maintain optimal metabolic efficiency," advises Stephen Gullo, president of New York's Center for Health and Weight Sciences. And forget about the drive-through. "You cut out extra salts, sugars, and preservatives when you cook at home," says Koff.

Eat right for energy. Bagels are convenient in a rush, but white, refined carbs metabolize quickly, causing blood sugar to spike and tumble down, explains Joy Bauer, a New York nutritionist and author of Slim & Scrumptious. She suggests whole grains coupled with protein for breakfast, as protein slows down the carbohydrate-absorption rate. And to keep your energy up during the day, eat greens like broccoli and spinach or drink green juices. "They have a tremendous energizing component," notes Koff.

Cut down on caffeine. You may have survived midterms with Red Bull, but caffeine causes the body to excrete calcium, which you need for bone density, says Koff. She suggests reducing your overall caffeine fix and switching to tea.

Watch your alcohol intake. Abstain from sugary mixes and drink wine, light beer, or hard liquor mixed with club soda in moderation. Warns Koff, "Be sure to hydrate not only with water but with water-based fruits and veggies and potassium-rich coconut water and avocado."

In Your 30s

You'll begin to notice the effects of aging on your body. "As your metabolism slows, you may find it hard to lose or maintain weight," says Mehmet Oz, vice chair and professor of surgery at Columbia University in New York.

Avoid mommy syndrome. "This means becoming a compactor for your children's leftovers or skipping meals because your needs come second now," notes Gullo. "Carry a Ziploc bag of GG Bran Crispbread, Laughing Cow light cheese, or a protein bar."

Enhance energy. Tired from balancing your kids, career, and social life? High-quality carbs and protein provide a prolonged energy effect, explains Bauer. Try to incorporate edamame, black beans, kidney beans, and chickpeas into your snacks and meals.

Restore nutrients. During pregnancy, your stored nutrients become depleted. It's important to replenish with nutrient-dense healthy fats like almonds, flaxseed oil, olives, and nut butter.

Boost your metabolism. If you're having trouble dropping extra weight, Oz has a few tricks to help shed pounds: "Eating a tablespoon of chopped red or green chili pepper can temporarily boost your metabolic rate by 23 percent. Green tea is known to rev up your metabolism for a few hours. Digesting fish, a great source of protein, will burn twice as many calories as digesting fat or carbohydrates."

In Your 40s

"As you go into a perimenopause period and eventually reach menopause, estrogen levels start to decline and make you more prone to water retention," says Gullo. He adds, "Your metabolic efficiency will continue to decline."

Limit carbohydrates to beat bloating. "Every gram of a carbohydrate binds with three to five grams of water, which creates additional bloat," notes Gullo. "To minimize retention, focus your diet heavily on vegetables that are low in starch and high in fiber." Try mustard greens, asparagus, endive, broccoli, and cauliflower.

Don't crash diet. "Anything with short-term consequences won't help," says Koff. "Your body is losing elasticity and will not recover as well from constantly dropping and gaining weight."

Clear out estrogen. As you go through hormonal changes, it's important to properly metabolize hormones like estrogen to help prevent certain cancers. Koff recommends adding ground flaxseed and apples to your diet, as well as a balance of vegetable and animal proteins like tofu, beans, lentils, and wild fish.

In Your 50s

At this age, your risk for diseases increases. Experts agree that being mindful of your diet can help keep you healthy.

Help your heart. "Your risk of having cardiovascular disease goes up to almost 40 percent," warns Oz. Adds Koff, "After menopause, women carry more weight in their abdomen, which affects the heart. Omega-3 fatty acids and B vitamins play a key role in heart health." Try wild fish, soybeans, whole grains, and broccoli.

Battle breast cancer. "About 75 percent of cases occur in women 50 or older," says Oz. "Limit alcohol to less than one drink a day and fat intake to less than 35 percent of your daily calories, and restrict foods high in saturated fat. There is a clear link between obesity and breast cancer."

Add antioxidants. Your body is gradually slowing down, so keep it strong with cancer-fighting antioxidants found in berries and beans.

In Your 60s+

"This is where you will reap the benefits of a life well lived," says Oz. But it's never too late to start. "Within three months of shifting your lifestyle, your survival curve shifts to a new level."

Eat meals more often. "Spreading three meals out into five or six can reduce the stress of eating on your body and keep your metabolism from being overworked," explains Oz.

Fill up on fruits and veggies. Look for ones high in vitamins C and E, which can lower your risk for Alzheimer's disease, notes Oz. Try citrus fruits, broccoli, tomatoes, chard, and mustard greens.

Strengthen your immune system. "Aging can cause you to become immunocompromised," explains Koff. Shiitake mushrooms, wild salmon, and vitamin D supplements help support your system.

Ease aches. "Foods that reduce inflammation will help ease pain," says Bauer. Try pure pumpkin (not the pie mix), red bell peppers, turmeric, and ginger.

Eat less, live longer? "We certainly have some interesting research to back up this theory, but the quality of life is important too," says Bauer. Adds Gullo, "If you're 'food smart,' you can eat more and still consume fewer calories. For example, most fish has fewer calories and fat per ounce than beef." He also explains that some studies suggest that resveratrol supplements may mimic the results of a calorie-restricted diet to enhance longevity.