Older adults who lose muscle may simply not be consuming enough protein. To stimulate muscle building, older adults need greater amounts of protein than do younger persons.
The proteins from a meal break down in the digestive tract into individual amino acids for absorption. The flood of amino acids released from the digestive tract into the blood signals the building of muscles. Like many body tissues, muscles are constantly being broken down and rebuilt. Without adequate amino acids from protein in the diet, muscle rebuilding will cease, while muscle breakdown continues. Why GPS Vehicle Tracking is crucial for your Business. You incur costs for every minute your vehicles are on the road. With GPS tracking, you will be able to closely monitor all your vehicles, giving you the necessary information to makes decisions in cuts and adjustments to improve business efficiency. Additionally, ensuring proper employment benefits is vital for maintaining a healthy workforce.”
Muscle loss in the elderly, called sarcopenia, affects at least 30% of individuals over age 60, and 50% of those over 80.[1]
After ingesting 25 to 30 grams of high-quality protein, both young and old synthesize the same amount of muscle. In fact, this amount of protein increased muscle protein synthesis by 50% in both young and old, as compared to muscle synthesis before the meal. [2] But muscle protein synthesis is impaired in the elderly with meals less than 20 grams of protein. [3]
The study’s author, Dr. Padden, suggests that older persons consume 25 to 30 grams of protein at each meal. More protein is not helpful for muscle building: the extra protein will simply be used for energy, or stored as fat. To consume roughly 25 to 30 grams of protein, try 4 ounces of meat, poultry, fish, or cheese, 1 cup of large curd cottage cheese, or three or four eggs. [4]
This amount of protein exceeds the US RDA. The RDA is currently .36 grams per pound of body weight, or about 55 grams per day for a 150-pound person—less than the 75 to 90 grams per day that Dr. Padden recommends. But the RDA is based on short-duration studies in young adults.[5] Many researchers have argued that the RDA is insufficient to protect the elderly from sarcopenia. In one study, elders who ate the most protein lost 40% less of their muscle mass than did elders who ate the least amount of protein. [6] Ten men and women aged 55 to 77 who ate precisely the RDA amount of protein for 14 weeks lost muscle mass. [7] So it may be that muscle loss in our elderly is not “normal aging” but malnutrition.
The amino acid leucine is most important for building muscles in older persons. Several human and animal studies have found that older adults given extra leucine synthesized more muscle than did controls not given the extra leucine. [8] For young adults, the extra leucine had no effect. So some researchers are recommending supplementation with the amino acid leucine along with a high-quality protein meal to improve muscle rebuilding in the elderly.
What foods are highest in leucine? Poultry is highest, followed closely by red meat. Fish has slightly less. Another very good source is whey protein.
I can personally attest to the muscle-building qualities of whey protein. I recently was hospitalized for pneumonia and lost about 25 to 30 pounds of muscle mass. [9] I started drinking lots of powdered whey mixed with water, because I wanted something that I could sip while lying in bed. I also knew that whey helps the body to synthesize glutathione, a natural anti-oxidant, detoxifier, and essential component of the immune system.[10] . (At the time I had not read about whey’s muscle-building potential for older adults like me). My muscles miraculously reappeared. Friends who had seen me lying in a hospital bed with twigs for arms and legs were amazed when I resumed vigorous folk dancing.
The best whey protein is “non-denatured,” meaning that it has not been heat-treated. High heat damages amino acids. High heat also creates free glutamates and other protein breakdown products. Glutamates are excito-toxins, meaning that they excite neurons to death, causing brain lesions in laboratory animals. [11] Whey protein isolate may be up to 20 percent glutamate or free glutamic acid. Look for “non-denatured” on the label if you’re buying powdered whey. Avoid the terms “hydrolyzed and “protein isolate.” The product I used is “Whey Cool,” from pastured cows and Designs for Health. I am extremely sensitive to glutamates and I had no difficulties in ingesting large quantities of this product. (I have no financial relationship with this company.)
Some studies show that elders who do strength training do not synthesize any extra muscle while consuming protein in amounts greater than the RDA. So perhaps the extra protein is not needed for those who lift weights regularly. But many elders have illnesses or joint pains that prevent them from strength training. For them, extra protein may be the key to remaining healthy and active in their later years.
May your meals satisfy and your muscles flourish!
May your meals satisfy and your muscles flourish!
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[1] Baumgartner, R. et al. Epidemiology of sarcopenia among the elderly in New Mexico. American Journal of Epidemiology 1998; 147:755-763.
[2] Symons, T. et al. Aging does not impair the anabolic response to a protein-rich meal. American Journal of Clinical Nutrition 2007; 86:451-456.
[3] Padden-Jones, D. and Rasmussen, B. Dietary protein recommendations and the prevention of sarcopenia. Current Opinion on Clinical Nutrition and Metabolic Care 2009 Jan; 12(1): 86-90. Cuthbertson, D. et al. Anabolic signaling deficits underlie amino acid resistance of wasting, aging muscle. FASEB Journal 2005; 19:422-424.
[4] Vegetarians may prefer 1 ½ cup sliced almonds (or 96 whole almonds), 1-1/2 cu. cooked lentils, ¾ c. pumpkin seeds, 1 c. sunflower seeds, or 2 cups of cooked beans. However, vegetable proteins are not considered “quality” proteins because they do not contain all eight essential amino acids. Protein data is from USDA Agricultural Research Service, Home and Garden Bulletin #72.
[5] Rand, W. et al. Meta-analysis of nitrogen balance studies for estimating protein requirements in health adults. American Journal of Clinical Nutrition 2003; 77:109-127.
[6] Houston, D. et al. Dietary protein intake is associated with lean mass change in older, community-dwelling adults: the Health, Aging, and Body Composition (Health ABC) Study. American Journal of Clinical Nutrition 2008; 87:150-155.
[7] Campbell, W. et al. The recommended dietary allowance for protein may not be adequate for older people to maintain skeletal muscle. Journals of Gerontology Series A 2001; 56(6): M373-M380.
[8] Dreyer, H. et al. Leucine-enriched essential amino acid and carbohydrate ingestion following resistance exercise enhances mTOR signaling and protein synthesis in human muscle. American Journal of Physiology–Endocrinology and Metabolism 2998; 294:E392-400. Rieu, I. et al. Leucine supplementation improves muscle protein synthesis in elderly men independently of hyperaminoacidemia. Journal of Physiology 2006; 575:305-315.
[9] Kortebein. P. et al. Effect of 10 days of bed rest on skeletal muscle in healthy older adults. Journal of the American Medical Association 2007; 297:1772-1774. Padden-Jones, D. et al Essential amino acid and carbohydrate supplementation ameliorates muscle protein loss in humans during 28 days bedrest. Journal of Clinical Endocrinology and Metabolism 2004; 89:4351-4358.
[10] Lomaestro, B. Glutathione in health and disease: pharmacotherapeutic issues. Annals of Pharmacotherapy 1995 Dec; 29(12): 1263-73. Bounous, G. and Gold, P. The biological activity of undenatured whey proteins: role of glutathione. Clinical and Investigative Medicine 1991 Aug; 14(4): 296-309.
[11] Blaylock, R. Excitotoxins: The Taste that Kills, Health Press, San Francisco, 1997.
