Vitamin Needs of Older Americans
Reviewed by Irwin H. Rosenberg, MD*
Since the beginning of the twentieth century, the percentage of Americans 65 and older has more than tripled – from 4.1% in 1900 to 12.8% in 1995, or approximately 33.5 million people.1 Within this group, the oldest portion – those over 85 years old – is increasing the most rapidly. By the year 2030, when the baby boom generation is in its senior years, 70 million Americans (20% of the total population) will be at least 65 years of age.2
Determining the nutritional needs of older adults is challenging because their physiology, medical conditions, lifestyles and social situations are different from those of younger people. The elder population is also the most diverse of any age group. Not only are the needs of a typical 65-year-old different from those of a typical 85-year-old, but variations exist among people of the same age.
While nutrition is crucial to good health at all stages of life, its role is particularly important at the extremes of the life cycle. In the elderly, ill health and poor nutrition can exacerbate each other, with poor nutrition contributing to vulnerability to illness, and illness contributing to decreased food intake, further compromising health and functional status. The special nutritional needs and concerns of elderly people are often overlooked because providers of care and elders themselves may not appreciate the role of nutrition in health.
New Dietary Recommendations for Older Age Brackets
Enough is now known about the nutritional needs of the elderly to allow for the establishment of specific dietary recommendations for this age group. The new Dietary Reference Intakes (DRIs), which are being issued in stages by the Institute of Medicine of the National Research Council, include separate recommendations for adults aged 51-70 years and those over the age of 70. This is a departure from previous editions of the Recommended Dietary Allowances (RDAs), which included only one set of recommendations for all adults aged 51 years and over.*3
The two sets of DRIs that have been released to date, the first pertaining to calcium and related nutrients and the second to the B vitamins, illustrate some important trends to be expected in all future recommendations for nutrient intakes.4.5 The new DRIs for older age categories are based, to the extent possible, on studies conducted in older people rather than on extrapolations from studies of younger people.5,6 Further, where sufficient data exist, the recommendations take into account the amounts of nutrients needed to reduce the risk or severity of chronic diseases rather than just the amount needed to prevent deficiency syndromes. Such considerations are particularly important for the elderly, for whom chronic diseases such as Alzheimer's disease, osteoporosis, coronary heart disease, cancer, cataract, and macular degeneration can have an enormous impact on the duration and quality of life.
For all age/gender segments, the new requirements are expressed in two different ways