& Alan Titchenal Monday, August 17, 2009
Age exerts major effect on healthy body weight
Developing generalized public health recommendations is complicated by the fact that "one size does not fit all." One of the most widely pronounced recommendations is to maintain a healthy body weight. But, what is healthy? The answer to this depends on many factors, including a person's age.
Question: How does age affect weight recommendations?
Answer: In middle-age adults, overall risk of death is greatest for both the thinnest and the heaviest individuals. Those with body weight in the middle range have the lowest risk. However, studies of people over 75 report that the heaviest individuals have the lowest risk of death. One study of community-dwelling seniors found that mortality rates were lower in obese than in normal-weight participants and mortality was highest in underweight individuals.
French researchers recently studied 125 seniors with an average age of 84. All of them were in the hospital for recovery from a variety of common problems such as fractures, neurological ailments, infections and cardiovascular disease. Those with the greatest levels of body fat were most likely to live and fully recover from their condition.
Based on their study in a hospital setting, the French researchers point out that their results suggest that it might not be justifiable to encourage very elderly overweight patients to lose weight. In fact, it could harm their health!
Q: What is a healthy weight in older people?
A: Based on research that has been conducted, it is probably best not to attempt significant weight loss after the age of 75. What makes the most sense is allowing the body to seek the weight at which a person functions best, both physically and mentally. The ideal weight for an older person likely depends on their genetics and their lifestyle.
There are no hard and fast rules about ideal body weight that apply to everyone equally at all ages. But, clearly, the recommendation to "maintain a healthy body weight" has a different meaning for older people. For most it appears to mean, "Don't lose weight." Of course, there are limits. Severe obesity can cause serious health complications at any age.
Q: Do any other public health recommendations fail the "one size fits all" test?
A: The recommendation to "eat more fruits and vegetables" can backfire. Perhaps a better way to make this recommendation is to say, "Eat enough fruits and vegetables." If someone already eats plenty of fruits and vegetables, eating more produce could displace important foods from other food groups and lead to nutrient deficiencies.
Older people generally have low calorie needs, so it is easier for them to overdo intake of fruits, vegetables and grains. This is because the most basic nutrient requirement is meeting protein needs with an adequate intake of foods from the meat and beans group and the milk and milk products group.
Along with enough of these good protein sources, fruits, vegetables and grains can be added to round out calorie needs. When protein needs are not met, the much too common geriatric condition of sarcopenia (loss of muscle) can develop.
Joannie Dobbs, PhD, CNS and Alan Titchenal, PhD, CNS
are nutritionists in the Department of Human Nutrition, Food and Animal Sciences,
College of Tropical Agriculture and Human Resources, UH-Manoa.
Dr. Dobbs also works with the University Health Service
© 2009 Honolulu Star-Bulletin -- http://starbulletin.com
Human Nutrition, Food & Animal Sciences · University of Hawai`i at Mānoa
1955 East-West Road · Honolulu, HI 96822
Page was last updated on: