To Your Health

Nutrition For the Elderly

By Dr. Nancy DiMarco, Ph.D.

The average age of the U.S. population is increasing and life expectancy is now at its highest.

According to the latest data from the Department of Health and Human Services, men can expect to live to be 73.6 years of age and women to live to be 79.4. Data from the U.S. Bureau of the Census and the National Center for Health Statistics indicated that persons over the age of 65 numbered 35 million in the year 2000 — 12.4 percent of the U.S. population or about one in every eight Americans.

Since 1990, the number of older Americans has increased by 12 percent or 3.7 million people, compared to an increase of 13.3 percent for the under-65 population. However, the number of Americans who will reach 65 over the next two decades (currently aged 45-64) increased by 34 percent from 1990 to 2000. By 2040, 10 percent of the population will be age 85 or older, according to the Social Security Administration.

This shift in the population has caused a strain on our health care system, and by one estimate, people over 65 are hospitalized 2.8 times more often per year than those under 65. In addition, we have more individuals living in either assisted living or nursing homes, and they require more care, have a higher incidence of chronic diseases and take a longer time to respond to medical therapy.

As a result of these significant changes in our population, we must put greater emphasis on all aspects of geriatric care — especially nutrition. The entire field of geriatric nutrition has evolved over the last two decades, and we now know much more about the needs of the elderly.

Aging is associated with changes in body composition. The most characteristic change that occurs as we age is a decrease in muscle mass. Many older individuals also have an increase in body fat, especially evident in the abdominal area. Because of these changes in body composition, nutritional recommendations that are used with younger and middle-aged adults are not applicable to this older segment of our population.

ENERGY REQUIREMENTS

A decrease in the basal metabolic rate (BMR), or the cost of keeping an individual's basic activities compatible with life, such as breathing and heart beat, is largely associated with this loss of lean muscle mass. BMR is the main determinant of total energy expenditure. The number of calories an older person requires must be adjusted based on a number of variables including presence or absence of disease, how physically active they are and social situation.

MACRONUTRIENT NEEDS

It is generally recommended that no more than 30 percent of total calories come from fat, with no more than 10 percent from saturated fat (animal fat). Carbohydrates should provide 55 to 60 percent of total calories per day with a greater emphasis on complex carbohydrates found in fruits, vegetables, whole grains, nuts and seeds.

Protein should provide 10 to 20 percent of total calories, but a disease state may alter this significantly.

A ballpark estimate of daily energy needs for an older individual based on body weight is 25-30 calories per kilogram(kg). So for example, a 150-pound, 65-year-old man would weigh 68 kg (divide pounds by 2.2 to determine kilograms). Multiply 25-30 by 68 for 1,700-2,000 calories per day.

Daily protein needs can also be estimated using body weight. A healthy individual needs approximately one gram of protein per kilogram of body weight per day. So, the same 68 kg male would need 68 grams of protein per day.

These values are only guidelines. To determine your individual needs, seek the advice of a registered dietitian.

MICRONUTRIENT NEEDS

The accompanying table provides the latest recommendations for vitamin and mineral intake, also called the Dietary Reference Intakes (DRI) from the National Academy Press (2000). These new recommendations offer guidelines for those persons aged 51 to 70 and for those older than 70.

In light of new findings, recommendations for many of these micronutrients have been adjusted. For example, the calcium requirement in 1989 was 800 mg per day. In this latest edition, the calcium requirement is now 1,200 mg per day, reflecting new data that emphasizes the benefit of calcium to prevent or decrease the risk of developing osteoporosis. Although vitamin A needs decrease as we age because of increased absorption, other nutrients, like calcium, increase.

Older adults require more folic acid and vitamins B-6 and B-12 to prevent some decline in cognitive function associated with aging and to reduce the risk of coronary artery disease. Decreased blood concentration of vitamins B-12 and folate have been linked to age-related hearing loss.

A food guide pyramid also has been developed to help older adults make better food choices. A unique feature of this pyramid is that the base rests on water to emphasize the critical importance of fluid intake and prevention of dehydration. The pyramid can be found on the Internet at: http://commentator.tufts.edu/archive/nutrition/pyramid.html.

Dehydration in older adults is a problem, especially among those over age 85 and those in nursing facilities. Dehydration is responsible for 6.7 percent of hospitalizations.

Fear of losing bladder control and increased arthritic pain resulting from frequent toilet visits may interfere with fluid consumption. But dehydration can result in constipation, fecal impaction, cognitive impairment, functional decline and death.

Good nutrition is of prime importance for the optimal health of the older person. Nutrition recommendations take into account many physiologic changes that occur with aging, but with good counseling, an individual can truly have some golden years ahead.

Dr. Nancy DiMarco is a research professor in the Department of Nutrition and Food Sciences, the nutrition coordinator for the Institute for Women's Health and coordinator of the master's program in Exercise and Sports Nutrition at Texas Woman's University. She can be reached at ndimarco@twu.edu.

For Further Information Contact:

Roy Kron]
Director of News and Information
Tel: (940) 898-3456]
e-mail: rkron@twu.edu