limited access to food. Tooth loss, infection, lesions, and other oral problems are prevalent in older adults and, if present, will contribute to altered dietary intake. Younger adults who participate in CACFP have various disabilities that may affect their nutritional status and functionality.

Vitamin B₁₂ merits special attention. Even though Table 5-2 shows that the prevalence of vitamin B₁₂ inadequacy is less than 3 percent for males and 7 to 9 percent for females, vitamin B₁₂ deficiency may be more prevalent than this. The discrepancy between the apparent prevalence of inadequacy and actual deficiency relates to the absorption of protein-bound vitamin B₁₂ by individuals over the age of 50 years. Ten to 30 percent of this older population may suffer from some degree of atrophic gastritis, leading to a decrease in stomach acid (IOM, 1998). Lack of gastric acid, in turn, leads to decreased absorption of the vitamin B₁₂ provided by animal foods. For this reason, the Institute of Medicine recommends that older adults obtain their Recommended Dietary Allowance (RDA) of vitamin B₁₂ mainly in the crystalline form, as from fortified foods (e.g., fortified breakfast cereals) or supplements (IOM, 1998). Data from What We Eat in America (USDA/ARS, 2010, Table 1) indicate that the mean daily intake of added (crystal-line) vitamin B₁₂ in fortified foods by adults ages 20 years and older was about 1 µg per day—far less than the RDA of 2.4 µg.

Elderly adults tend to have poor dairy and vitamin D intake, decreased sun exposure as well as reduced dermal synthesis of 1,25-OH₂-D, and secondary hyperparathyroidism, all of which contribute to increased risk for poor bone health and fracture risk in this population. Concentrations of provitamin D₃ in the epidermis are inversely related to age (MacLaughlin and Holick, 1985), which results in decreased production of vitamin D from sunlight exposure. Estimates of vitamin D synthesis in elderly adults suggest about a 70 percent decrease in the elderly compared to young adults (Holick et al., 1989). In women, bone loss occurs as a result of low estrogen levels that accompany menopause and the combined effects of other age-related changes on vitamin D and calcium metabolism. Estrogen has a regulatory role in synthesis of 1,25-OH₂-D (Caniggia et al., 1987), and the reduction of estrogen as a result of menopause is correlated with a progressive increase in parathyroid hormone, which in turn increases bone