The health benefits of a vegan diet - one that excludes all forms of animal protein - have been espoused by its proponents in the popular press. Before swearing off fish, eggs and meat forever, however, researchers at Hebrew SeniorLife's Institute for Aging Research caution the public to look at their studies, which indicate that overall protein intake - as well as animal protein consumption - promotes bone health.
In a May 2010 study published in Osteoporosis International, senior Institute investigator Marian T. Hannan, D.Sc., M.P.H., found that seniors who consume higher levels of dietary protein are less likely to suffer hip fractures than seniors whose daily dietary intake is less. The study, which examined the daily protein intake of 946 seniors from the Framingham Osteoporosis Study, found that individuals who were in the lowest 25 percent of dietary protein intake had approximately 50 percent more hip fractures than those who consumed greater amounts of dietary protein (all within normal intakes). Those who suffered hip fractures consumed less than the 46 grams of dietary protein per day recommended for adults.
Dr. Hannan recommends that older women consume at least 46 grams of protein per day, and that older men consume at 56 grams of protein daily. This can come from both animal sources (meat, poultry, fish, eggs, milk, cheese and yogurt) and plants (legumes, grains, nuts, seeds and vegetables).
This study builds on Dr. Hannan's 2000 study, published in the Journal of Bone and Mineral Research, which examined the relationship between baseline dietary protein and subsequent four-year change in bone mineral density . Lower protein consumption was significantly related to bone loss, suggesting that protein intake is important in maintaining bone or minimizing bone loss in elderly people. Further, the study showed that higher intake of animal protein does not appear to affect the skeleton adversely in this elderly population.
What does this mean for the public? Dr. Hannan says that individuals should consult their physician or a trained nutritionist before making extreme changes to their diet. Some older adults suffer from conditions that make protein intake particularly important to the healing process. And, vegetable proteins often lack important amino acids and must be consumed in combinations to make them as complete and, thus equal, to the quality of animal protein.