1. Get your potassium
Stay strong as you age by eating potassium-rich vegetables — potatoes, leafy greens — and fruits, such as bananas and papayas. People 65 and older who loaded up on these foods kept as much as 3.6 percent more lean muscle tissue than those who consumed less, according to a study in the American Journal of Clinical Nutrition. Strive for the recommended 4.7 grams daily of potassium; eating five to nine servings of fruits and vegetables should do it, notes Daphne Miller, M.D., a San Francisco-based physician and author of The Jungle Effect, which looks at the diets of some of the world's healthiest people.
2. Think positively
A cheery outlook may actually extend your life. An analysis of 30 follow-up studies in the Journal of Happiness Studies found that being happy can protect you from becoming ill. Indeed, the effect of happiness on lifespan is about as strong as not smoking, say researchers. Another study showed that people who report being happy and satisfied with their lives are more likely to enjoy good health and fewer long-term, limiting health concerns.
3. Lace up
Are your sneakers buried in your closet? Go dig them out. According to a study in the British Journal of Sports Medicine, if you stay aerobically fit, you can delay biological aging by 10 or more years and prolong your independence. A study in Circulation that tracked participants for an average of 7.5 years showed that exercise is inversely related to death: The more you work out, the longer you'll likely live.
4. Join the culture club
Probiotics, the so-called friendly bacteria, may play a role in the prevention of certain diseases. More research is needed, but they've been linked to improved immunity and decreased rates of colon cancer, says Miller. "Anecdotally, some of the zones where people live the longest also happen to be places where the diet has a variety of fermented foods, which contain probiotics," she adds. Include these foods — yogurt with live cultures, for example, as well as unpasteurized kimchi — in your diet, and consider taking a daily probiotic supplement (read the label for dosage), such as Lactobacillus GG or Bacillus coagulans 30, says Weil.
5. "B" smart
Keep your brain healthy with vitamin B12, found in such foods as seafood and poultry. A recent study found that people with low blood levels of this nutrient experienced a faster decline in cognitive function than those with higher levels. On the flip side, people who consume plenty of B12-rich foods are six times less likely to experience brain shrinkage.
6. Make fish a habit
Certain fatty fish contain high amounts of two omega-3s critical to healthy aging — eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Numerous studies show that these healthy fats can help lower the risk of heart disease and heart attacks. In a 2008 Neurology study, researchers found that older people who ate omega-3-rich fish at least three times a week had a nearly 26 percent lower risk of brain lesions associated with stroke and dementia than those who didn't eat fish regularly. EPA and DHA also may protect your eyes; people who eat fatty fish just once a week are 50 percent less likely to develop age-related macular degeneration, the leading cause of blindness in older adults. Aim for two servings of fatty fish a week, advises Miller. Good sources include herring, salmon, tuna, and trout.
7. Pal around
Don't let connections fall by the wayside. Research suggests that loneliness can increase the risk of high blood pressure, depression, and Alzheimer's disease, as well as lower immunity. On the other hand, "socializing appears to enhance health, and may even increase longevity," says Thomas Perls, M.D., an associate professor of medicine and geriatrics at Boston University's School of Medicine and the founder and director of the New England Centenarian Study.
8. Get more D
"Vitamin D is one of our major defenses against many age-related diseases," says Weil. Indeed, a large study in the Archives of Internal Medicine found that people with the lowest blood levels of D had a higher risk of dying from all causes during the median 7.7-year study period. Additional studies indicate vitamin D may help protect against cardiovascular disease, high blood pressure, certain cancers, and some autoimmune disorders. Dietary sources of D include fish, eggs, and fortified milk; our bodies also make D in response to sunlight.
9. Do Tai Chi
Often described as "meditation in motion," this ancient form of stretching and balance can help you age well. Numerous studies suggest that tai chi may improve everyday physical functioning, lower blood pressure, ease chronic pain, relieve anxiety, and slow bone loss after menopause. It also shows promise for alleviating insomnia, a common problem in the elderly.
10. Reduce red meat
Make red meat an occasional indulgence — no more than once a week, suggest our experts. Its saturated fat can clog arteries, raising the risk of cardiovascular disease. It may also boost cancer risk. A recent study found that people who consumed the highest amounts of red meat (equal to about a quarter pound of hamburger a day) had a 20 to 60 percent higher risk of developing certain cancers than those who ate less. Red meat also contains high levels of iron, too much of which has been linked to a greater risk of cardiovascular disease, diabetes, and Alzheimer's disease, says Perls. Replace red meat with fish, poultry, or whole, organic soy foods such as tempeh.