Eating and Appetite: Common Problems and Practical Remedies (2004)

Older people are at risk for impaired appetite, lack of motivation to eat, chewing and swallowing disorders, constipation, diarrhea, and weight loss. Some older people, such as those with diabetes or osteoarthritis, may need to prevent weight gain, lose weight, and make lower-calorie food choices. Physiological, psychological, social, and economic factors contribute to less healthy eating behaviors and digestive disorders. PHYSIOLOGICAL FACTORS THAT ALTER EATING AND APPETITE As people age, a number of physiological factors alter eating and appetite. Food intake usually decreases, even in healthy older adults (McDonald and Ruhe, 2004; Wilson and Morley, 2003). This physiological decrease in food intake is called the of aging. Generally, decreases in food intake are greater in men than in women. People start to lose weight when their food intake is not sufficient to meet energy needs for daily activities and for normal metabolism. Both muscle and fat are lost when body weight declines. Among older people, weight loss is associated with frailty, functional impairment, immune disorders, pressure ulcers, hip fractures, cognitive impairment, low quality of life, and increased mortality (Wilson and Morley, 2003). Wilson and Morley (2003) note that while dietary restriction in animal models seems to prolong life, weight loss in older people shortens life. Therefore, despite the interesting results of studies in animals that show that food restriction is beneficial, it is critically important to monitor and prevent weight loss in older people. One physiological change that contributes to decreases in food intake and the anorexia of aging is die loss of muscle tissue. Muscles use much of our energy, so loss of muscle means less food is needed. Physical activity helps maintain muscle mass. Therefore, physically active people experience fewer declines in muscle mass and food intake as they age. With aging, the stomach releases food more slowly into the intestine, which leads to earlier feelings of satiety (fullness) during a meal and lower intakes of food. Certain hormones that sense satiety and energy expenditure are also altered in ways mat decrease food intake. The ability to adjust subsequent food intake after under- or overeating is lessened with advancing age (Morley, 2001). Sensing and responding to thirst is also impaired, which increases the risk of dehydration. Most chronic diseases that affect older people are asscxiated with negative energy balance (e.g., more energy is expended than is taken in as food) and weight loss (Wilson and Morley, 2003). Weight loss associated with low food intake is common in AlZheimerk disease. Several diseases are associated with increased energy needs, among them congestive heart failure and chronic obstructive pulmonary disease. The persistent tremors of Parkinson's disease use extra energy. Compounds called cytokines that decrease appetite are released during some diseases. For example, infectious diseases can increase energy needs and at the same time interfere with appetite. Changes in taste and smell associated with aging, chronic health problems, and medications can interfere with appetite and the ability to enjoy food (Wilson and Morley, 2003). Stronger flavorings and seasonings may enhance enjoyment of food and stimulate appetite. Therapeutic diets low in sodium, sugar, and fat can contribute to poor appetite in some because die food just does not taste very good. Families, caregivers, and the healthcare team need to find a balance between the benefits and risks of therapeutic diets for older people experiencing poor appetite and weight loss. Several medications have direct or indirect side effects that impair food intake, appetite, and intestinal function in older people (Pick et al., 2003). Appetite-suppressing effects that could lead to anorexia and malnutrition are associated with central nervous stimulants (dextroamphetamine [Adderall], methylphemdate [Ritalin], methamphetamine [Desoxyn], pemolin [Tylert], and fluoxetine [Prozac]). …