Issue Briefings for Health Reporters

Physiological changes that occur as people age can affect their nutrition and health. Their senses of smell, taste and thirst change, as do nutrient requirements and how they metabolize food, says Lola O’Rourke, R.D., a spokesperson for the American Dietetic Association. Older people lose lean body mass and are less active. Fewer calories are needed to maintain weight, but they must still take in the same levels of other nutrients. Physical activity is necessary to maintain a normal weight and good bone health.

Dinner for One

Social and psychological changes also influence relationships to food as people age. The elderly may live alone for the first time in years. Hands may not be as agile for preparing food. Shopping may be physically or logistically difficult. Depression or alcoholism may set in after a spouse dies. Having lost the social context for dining, people may eat less and with more monotony. “They may settle for a ‘tea-and-toast’ mentality when it comes to food,” says Melanie Polk, R.D., of the American Institute for Cancer Research.[9]

Food-borne illnesses are more likely to sicken people older than 65, according to the U.S. Department of Agriculture, because immune systems weaken and production of protective stomach acids decline with age. The USDA recommends the elderly avoid raw fish, shellfish, eggs, meat or poultry, or unpasteurized milk, cheese or juice.[1]

Eating Right for a Lifetime

Aging changes the body’s need for many nutrients. To help adjust to those changes, the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University issued a modified food guide pyramid for people 50 and older — “and especially for those 70 and older” — to help them eat well.

The pyramid is designed to encourage options that contain more vitamins, minerals and other nutrients per calorie than other foods, says Tufts nutritional biochemist Alice Lichtenstein, D.Sc. Dark green, red, orange, yellow or other brightly colored vegetables and deeply colored fruits make the best choices, she says. “Choose romaine over iceberg lettuce,” she urges, “and pick peaches and apricots rather than apples.”

Whole grains and cereals, nuts and dry beans provide needed fiber, as do fruits and vegetables. Fish and poultry provide protein without a lot of saturated fat (and calories). Whole fruit is considered healthier than juice.

The Tufts pyramid also emphasizes the need for added fluids. Age disturbs the connection between the sense of thirst and actual hydration, meaning people may be more dehydrated than they feel, especially when the weather is hot, Lichtenstein says. Older people should drink eight glasses of water or other liquids every day — juice, milk, tea, coffee or low-sodium soup.

Other changes vary with the type of nutrient. While the body’s need for calories declines, protein requirements rise. The need for vitamin A declines because aging bodies absorb more than younger ones do. But older adults need more calcium to maintain bone health, and more folic acid, vitamin B-6 and vitamin B-12 to avoid cognitive deficiencies. Older people with limited intake of dairy products or who spend little time outdoors may be getting too little vitamin D.

Some experts recommend a multivitamin, although that remains up for debate, says Joel Mason, M.D., director of the vitamin and cancer lab at Tufts. However, vitamins are cheap and have few side effects in recommended doses, he says. “But there are more good things in foods than we know about,” he says, “so it’s best to obtain nutritional needs through a good diet.”

Prescription drugs may also interfere with proper nutrition. Iron supplements for anemia can cause upset stomach, loss of appetite or constipation. Liquid drugs contain sorbitol, a sugar that causes diarrhea in some people. Grapefruit juice inhibits production of key enzymes, increasing blood levels of some medications. [8]

Finally, less may be more, says Judith Finkelstein, Ph.D., of the National Institute on Aging. New NIA research is examining whether reducing energy balance by 25 percent through eating less and exercising more can result in a longer life.

Judith Finkelstein, Ph.D.
National Institute on Aging
(301) 496-1752 (PIO office)