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Article Excerpt
The results of the Third National Health and Nutrition Examination Survey (NHANES III) (Alaimo et al., 1994) agree with the conclusions of other studies that the calcium intake of many African Americans is below recommended levels (National Research Council, 1989) and especially below the new calcium goals (Dietary Reference Intakes) for the American population (National Academy Press, 1997; Yates, Schliker, & Suitor, 1998). The limited intake of calcium by African Americans places this subgroup of the American population at risk for chronic diseases that may be alleviated by achieving adequate calcium. Although many African Americans consume milk, the consumption of dairy products--a major source of calcium in the United States--by African-American men and women is significantly lower than that of White men and women (Shimakawa et al., 1994; Koh & Chi, 1981). Osteoporosis associated with calcium-intake deficiencies and possibly hypertension contributes to the high cost of medical care in the United States (Riggs, Peck, & Bell, 1991; Joint National Committee, 1993).
Prevalence of deficiencies in lactase, an enzyme required to metabolize the primary milk sugar lactose, is blamed for the low intake of dairy products among African Americans (Pollitzer & Anderson, 1989). Although the consumption of milk and dairy products is inadequate in terms of calcium intake, nutrient supplementation is not a solution for many African Americans. Results from the 1992 National Health Interview Survey Epidemiology Supplement (Slesinski, Subar, & Kahle, 1996) indicate that of the 1,353 Blacks surveyed, three-fourths (77.2 percent) seldom or never used any vitamin and mineral supplement, less than 5 percent (4.4 percent) used supplements occasionally, and 18.4 percent used them daily.
Commonly called the "silent disease" because pain or symptoms are not experienced until a fracture occurs, osteoporosis is a metabolic bone disease characterized by low bone mass, which makes bones fragile and susceptible to fracture. While African-American women tend to have higher bone mineral density than White women have, they are still at significant risk of developing osteoporosis. Furthermore, as African-American women age, their risk of developing osteoporosis more closely resembles the risk among White women. So, as the number of older women in the United States increases, an increasing number of African-American women with osteoporosis can be expected (National Institutes of Health, 1998).
Background
The literature is replete with studies indicating that calcium intakes of African Americans are below the recommended dietary guidelines (e.g., Alaimo et al., 1994), as well as the new calcium intake standards set by the Institute of Medicine (National Academy Press, 1997). In addition to verifying the poor status of calcium intake among African-American adults, much of the literature focuses on the dichotomy of lactose intolerance and bone densities of African Americans. Lactose intolerance is thought to be the primary barrier to consumption of milk and dairy products among African Americans (Buchowski, Semenya, & Johnson, 2002). The empirical work on lactose intolerance among African Americans, however, does not establish that African Americans choose not to consume milk because of gastrointestinal distress. Researchers have found that lactose intolerance among some African Americans may be overestimated because of lactose digesters' belief that consumption of milk leads to this distress (Johnson, Semenya, Buchowski, Enwonwu, & Scrimshaw, 1993). Even with lactose intolerance, small quantities of milk can be consumed with little or no discomfort, and specialty milk products and lactase tablets are available to ameliorate the symptoms related to lactose consumption. In addition, promising dietary management strategies are available, such as consuming lactose-containing dairy foods more frequently and in smaller amounts as well as with meals, eating live culture yogurt, using lactose-digestive aids, and the consumption of calcium-fortified foods (Jackson & Savaiano, 2001).
The other side of the dichotomy is bone mineral density and osteoporosis. A major reason for the sense of security regarding calcium-intake research may be the higher bone mineral density of African-American women (e.g., Luckey et al., 1989) coupled with their lower rates of osteoporosis. The implications are that high bone mineral density will protect African Americans from osteoporosis and symptoms of calcium deficiency. Silverman and Madison (1988) found that the incidence of age-adjusted fracture rates for non-Hispanic White women is greater than twice the rate for African Americans. But low risk does not translate into no risk. A fact sheet from the National Institutes of Health (1998) states that
[A]pproximately 300,000 African-American women currently have osteoporosis; between 80 and 95 percent of fractures in African-American women over 64 are due to osteoporosis; African-American women are more likely than White women to die following a hip fracture; as African-American women age, their risk of hip fractures doubles approximately every 7 years; [and] diseases more prevalent in the African-American population, such as sickle-cell anemia and systemic lupus erythematosus, are linked to osteoporosis.
Some researchers have developed a prudent approach to this dichotomy. One group concluded that the "higher values of bone densities in African-American women, compared with White women are caused by a higher peak bone mass, as a slower rate of loss from skeletal sites comprised predominantly of trabecular bone. Low-risk strategies to enhance peak bone mass and to lower bone loss, such as calcium and vitamin D augmentation of the diet, should be examined for African-American women" (Aloia, Vaswani, Yeh, & Flaster, 1996). To promote higher intakes of calcium more effectively, researchers and nutrition educators need to know more about food practices in relationship to dietary calcium. However, little information is available on the effect that food practices of older African Americans may have on nutrient intake, particularly calcium (Cohen, Ralston, Laus, Bermudez, & Olson, 1998).
The Council on Aging's congregate meal feeding program is an excellent means of studying the problem of dietary calcium barriers among African-American elders. Even though the Council's meals provide one-third of the RDA for all nutrients, African-American participants consumed less calcium,...
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