Protein Intake For Over 65s

We often hear the comment, we need a high protein diet for energy. Special diets are recommended, powder combinations are manufactured and marketed to especially get the protein levels up. Others will recommend meat and dairy products are essential for health and well-being. But is it really the answer for all age groups?

      It is more than that. A low protein intake is actually the recognized recommended levels, and these levels are associated with a major reduction in cancer and overall mortality in middle age, that is under age 65, but not necessarily in older populations. When it comes to diabetes deaths, lower overall protein intake is associated with a longer life at all ages. However for cancer, it seems to flip around age 65.    

A study followed sedentary individuals over the age of 65 for 12 years and found they lose about one percent of their muscle mass every year. If you force people to lie in bed for days at a time, anyone would lose muscle mass, but older adults on bed-rest may lose muscle mass six times faster than young people also on bed-rest. So, it's use it or lose it for everyone, but the elderly appear to lose muscle mass faster, so they better use it. The good news is that in contrast to the 12-year U.S. study, a similar study in Japan found that the “age-related decreases in muscle mass were trivial.”

Why the difference? It turns out that in the Japanese study, “the participants were informed about the results of their muscle strength, [so] they often tried to improve it by training before the next examination.” This was especially true among the men , who got so competitive their muscle mass increased with age, which shows that the loss of muscle mass with age is not inevitable—you just have to put in some effort. And, research reveals that adding protein doesn't seem to help. Indeed, adding more egg whites to the diet didn't influence the muscle responses to resistance training, and that was based on studies funded by the American Egg Board itself.

Even the National Dairy Council couldn't spin it: Evidently, strength “training-induced improvements in body composition, muscle strength and size, and physical functioning are not enhanced when older people…increase their protein intake by either increasing the ingestion of higher-protein foods or consuming protein-enriched nutritional supplements.”

Is there anything we can do diet-wise to protect our aging muscles? Eat vegetables. Consuming recommended levels of vegetables was associated with basically cutting in half the odds of low muscle mass. Why? “The alkalizing effects of vegetables may neutralize the mild metabolic acidosis” that occurs with age, when that little extra acid in our body facilitates the breakdown of muscle. I've discussed before how “muscle wasting appears to be an adaptive response to acidosis.”  We appear to get a chronic low-grade acidosis with advancing age because our kidney function starts to decline and because we may be eating an acid-promoting diet, which means a diet high in fish, pork, chicken, and cheese, and low in fruits and vegetables. Beans and other legumes are the only major sources of protein that are alkaline instead of acid-forming. And indeed, a more plant-based diet—that is, a more alkaline diet—was found to be positively associated with muscle mass in women aged 18 to 79.

So, if we are going to increase our protein consumption after age 65, it would preferably be plant-based proteins to protect us from frailty. No matter how old we are, a diet that emphasizes plant-based nutrition “is likely to maximize health benefits in all age groups.”

— Michael Greger MD, FACLM, July 16,2019