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free tools for patients, expert nutrition advice and information on updated
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Educate your patients on the importance of 3-A-Day of Dairy: Here's
a great
tool (PDF: 618k) to show families how to get their 3-A-Day of Dairy
every day for stronger bones.
Developed in conjunction with The American Academy of Family
Physicians, The American Academy of Pediatrics, The American Dietetic
Association, and The National Medical Association.
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Dairy Council Digest Archives
Special Dietary Needs of Mature Americans
Vitamins
Vitamin D.
The new vitamin D recommendation is 10µg (400 I.U.)/day for adults ages 51 through 70 years, a level twice as high as the levels set for earlier adulthood and childhood (14) or the 1989 RDAs (28). For adults >70 years, 15mg (600 I.U.)/day is recommended, or three times more than for individuals through age 50 or than the level previously recommended (14,28). These new dietary recommendations for vitamin D are based on the amount of vitamin D to maintain blood levels of 25-hydroxyvitamin D associated with optimal bone health. Vitamin D is obtained from the diet, especially vitamin D-fortified milk, and from cutaneous synthesis upon exposure to sunlight (14). The vitamin D recommendations assume limited availability of vitamin D from exposure to sunlight (14).A combination of lack of exposure to sunlight, age-related decreased cutaneous and endogenous synthesis of the metabolically active form of vitamin D, and a low dietary intake of vitamin D increases mature adults' risk for vitamin D deficiency and contribute to their increased need for this vitamin (14,16).
Vitamin D deficiency is characterized by inadequate skeletal mineralization or demineralization. Low blood levels of 25-hydroxyvitamin D, a clinical indicator of vitamin D deficiency, are often found in mature adults, especially those who are homebound or institutionalized (29–34).A number of studies indicate that increasing the vitamin D intake of older adults, either alone or together with calcium, reduces bone loss and risk of skeletal fractures (35–40). When vitamin D intake was increased by either 100 or 700 I.U./day for two years in a double-blind, randomized trial involving 247 older women, loss of hip bone mineral density was less in the group receiving 700 I.U. than in the group receiving 100 I.U. of vitamin D/day (36). Bone loss and risk of hip, spine, and total body fractures were reduced in 389 adults over age 65 who received 500mg calcium/day plus 700 I.U. vitamin D/day, as opposed to a placebo, for three years (37). Similarly, bone mineral content increased and vertebral and nonvertebral fracture incidence decreased in over 3,400 older French women given 1,200mg calcium/day and 800 I.U. vitamin D/day for 18 months (38).
"For the first time, new dietary recommendations for calcium and related nutrients and B vitamins for mature adults include two age categories: 51 through 70 years and >70 years."
B Vitamins.
With the exception of folate, new recommended intakes for B vitamins (15) have not changed appreciably from the 1989 RDAs (28). However, recommendations for folate and vitamin B12 for mature adults deserve special consideration.
The DRI for folate is 400mg/day for all adults 51 years of age and older (15), an increase from the 200mg folate/day for men and 180mg folate/day for women recommended in 1989 (28). Because there is no evidence that aging per se reduces folate utilization, folate recommendations are the same for both older and younger adults (15). The primary indicator used to estimate the folate requirement of adults is the amount of dietary folate equivalents to maintain red cell folate, which reflects tissue folate stores (15).
Ancillary data on plasma homocysteine and folate concentrations were also considered in estimating folate recommendations for adults (15). Aging increases blood levels of homocysteine which is associated with increased risk of vascular disease (41).
Although folate intake has been inversely related to blood homocysteine levels, a variety of other factors (i.e., vitamin B12, vitamin B6, age, gender, race, genetic abnormalities, smoking) also influence blood homocysteine levels (42,43). Further, the relationship between homocysteine levels and cardiovascular diseases has yet to be conclusively established. For these reasons, blood homocysteine level alone is insufficient to derive recommended intakes of folate (15).Although folate intake of many older adults is low (15,21), meeting recommended intake levels of folate may now be easier. As of January 1, 1998, all enriched cereal grains are required to be fortified with 1.4mg folic acid/kg of grain (44). Because excess folate intake may delay the diagnosis of vitamin B12 deficiency (masking effect), a Tolerable Upper Intake Level (UL)—the maximum intake considered to be safe—of 1,000mg folate/day is set for all adults.
A vitamin B12 intake of 2.4µg/day is recommended for all adults 51 years of age and over (15). Although most Americans obtain sufficient vitamin B12 from foods (e.g., meat, fish, poultry, milk), about 10 to 30 percent of mature adults lose their ability to adequately absorb protein-bound vitamin B12 in foods. This loss may be caused by a decrease in gastric acidity and/or atrophic gastritis from chronic Helicobacter pylori infection (15,45,46). In contrast, the percentage absorption of crystalline vitamin B12 does not appear to decrease with age. Consequently, synthetic vitamin B12 from fortified foods or vitamin supplements is recommended for adults over age 50 to help meet their recommended intake for this vitamin (15).
Recognizing that many older adults consume vitamin supplements (47) and that megadoses of vitamins may adversely affect health, upper limits (ULs) for vitamin D (50mg/day), niacin (35mg/day), vitamin B6 (100mg/day), and folic acid (1,000mg/day) have been established (14,15). Lack of evidence prohibits the establishment of ULs for other vitamins.
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