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Part I Introduction to Nutrition Care in Older Adults

older were obese, while 43% of men ages 65 to 74 and 27% of men age 75 and older were obese (1). While these percentages have not changed significantly in the last seven years, they are of concern due to the increase in chronic disease risk associated with obesity. The US Healthy Eating Index (HEI), a summary of overall diet quality, showed that in older people, consumption was lowest for whole grains, dark green and orange vegetables, legumes, and milk (10). The diet quality of Americans, as assessed by the HEI- 2010, showed that scores declined for sodium and increased for whole fruit and empty calories (P < .05). No significant change was seen for the remaining HEI- 2010 component scores or in the total score (11). Diet quality varies by income level. Many changes in the economy, policies related to nutrition, and food processing have occurred within the United States since 2000, and the net effect on dietary quality has been difficult to measure. These changes may have affected various socioeconomic groups differentially. In a study to investigate trends in dietary quality from 1999 to 2010 in the US adult population and within socioeconomic subgroups, the Alternate Healthy Eating Index 2010 (AHEI-2010), an 11-dimension score (0 to 10 range for each component score and 0 to 110 for the total score), was used to measure dietary quality (12).

Although a steady improvement in AHEI-2010 was observed across the 12-year period, the overall dietary quality remained poor. Better dietary quality was associ- ated with higher socioeconomic status, and the gap widened with time (12). Older women were more likely than older men to live in poverty (11% vs 7% in 2010), as were older minority populations (18% of blacks and 18% of Hispanics) vs non-Hispanic whites (7%). Older minority women experience higher rates of poverty (20.5% black women and 20.9% Hispanic women) than their male counterparts (14.2% black men and 14.2% Hispanic men) (1).

ORGAN FUNCTION, THE AGING

BODY, AND NUTRITION Animal studies and preliminary studies in small numbers of older adult human subjects suggest that alterations in gut structure/function and/or hormonal regulation of appetite may be altered in older adults. Box 1.1 summarizes the variety of potential gastroin- testinal sensory and motor function alterations and pos- sible stimulatory or inhibitory effects of selected hormones and neurotransmitters on appetite regulation. Multiple alterations in gastrointestinal anatomy and physiology impair motility and contribute to com- plaints of dysphagia, anorexia, dyspepsia, and consti- pation in older adults, as described in Table 1.1 and in

BOX 1.1 Possible Contributors to Age- Associated Physiological Changes in Appetite and Food Intake

Poor dentition: ●

●

multiple missing, rotten, decayed teeth lack of/ill-fitting dentures ● periodontal disease ● dry mouth

Declines in sense of taste and smell: ●

Altered gastrointestinal function: ●

●

alteration in the pleasantness of taste of a specific food (sensory-specific satiety)

reduced sensitivity to gastric distention impaired gastric accommodation ● delayed gastric emptying

● increased satiating cytokine activity

Age-related changes in selected hormones and neurotransmitters: ●

➤ ➤ ➤ ➤

Those that may increase appetite/food intake: testosterone: decreased activity opioid: possible decreased activity ghrelin: possible decreased activity

neuropeptide Y (NPY): possible decreased activity

➤ ➤

orexins: possible increased concentrations leptin: increased resistance

● Those that may decrease appetite/food intake: ➤

cholecystokinin (CCK): increased circulating levels, increased cerebrospinal fluid levels, increased sensitivity to satiating effects

➤

cocaine-amphetamine-regulated transcript: possible increased levels

➤ ➤

peptide YY: possible decreased sensitivity galanin: reduced sensitivity

Source: Adapted from McPhee I. The anorexia of aging. Clin Geriatr Med. 2007;23(4):742, with permission from Elsevier.

Grassi et al (13,14). In Box 1.2 (see page 6), Morley describes changes in nutrient absorption that occur as people age, some as the result of chronic disease (ie, chronic gastritis with bacterial overgrowth, celiac disease, pancreatic insufficiency) and some as the result of medication’s impact on micronutrient absorp- tion (15). The addition of foods or supplements rich in prebiotics (ie, fruct ol igosaccharides, inulin) and/or pro- biotics (ie, microorganisms) to the older adult’s diet may enhance the immune system, improve lactose tol- erance, treat diarrhea, and prevent translocation of harmful bacteria across the gut wall (16-18).