Should We Increase Our Protein Intake After Age 65?

A study that purported to show that diets high in meat, eggs, and dairy could be as harmful to health as smoking supposedly suggested that “[p]eople under 65 who eat a lot of meat, eggs, and dairy are four times as likely to die from cancer or diabetes.” But if you look at the actual study, you’ll see that’s simply not true: Those eating a lot of animal protein didn’t have four times more risk of dying from diabetes—they had 73 times the risk. Even those in the moderate protein group, who got 10 to 19 percent of calories from protein, had about 23 times the risk of dying of diabetes compared to those consuming the recommended amount of protein, which comes out to be about 6 to 10 percent of calories from protein, around 50 grams a day.

So, the so-called low protein intake is actually the recommended protein intake, associated with a major reduction in cancer and overall mortality in middle age, 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. I discuss this in my video Increasing Protein Intake After Age 65.

“These results suggest that low protein intake during middle age followed by moderate to high protein consumption in old adults may optimize healthspan and longevity.” Some have suggested that the standard daily allowance for protein, which is 0.8 grams of daily protein for every healthy kilogram of body weight, may be fine for most, but perhaps older people require more. The study upon which the recommended daily allowance (RDA) was based indicated that, though there was a suggestion that the “elderly may have a somewhat higher requirement, there is not enough evidence to make different recommendations.” The definitive study was published in 2008 and found no difference in protein requirements between young and old. The same RDA should be adequate for the elderly. However, adequate intake is not necessarily optimal intake. The protein requirement “studies have not addressed the possibility that protein intake well above the RDA could prove beneficial,” or so suggests a member of the Whey Protein Advisory Panel for the National Dairy Council and a consultant for the National Cattlemen’s Beef Association.

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 bedrest may lose muscle mass six times faster than young people also on bedrest. 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 “[a]ge-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? “[T]he 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 “[m]uscle wasting appears to be an adaptive response to acidosis.” (See my video Testing Your Diet with Pee and Purple Cabbage for more on this.) 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.”


What was that about a study that purported to show that diets high in meat, eggs, and dairy could be as harmful to health as smoking? See my video Animal Protein Compared to Cigarette Smoking.

Protein is so misunderstood. For more on the optimal amount of protein, see Do Vegetarians Get Enough Protein? and The Great Protein Fiasco.

Interested in learning more about the optimal source of protein? See:

What about the rumors that plant protein is incomplete? See The Protein Combining Myth.

For information on buffering the acid in our blood, see Testing Your Diet with Pee and Purple Cabbage.

And, for more on acid/base balance, see:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Why There Is so Much Commercial Corruption in Nutrition

The prevalence of chronic diseases such as diabetes has skyrocketed, as has the number of articles published about diabetes in medical journals. “Why does our wealth of academic knowledge not translate more directly to improving the human condition?” Perhaps our over-attachment to the reductionistic mindset that proved so successful with acute deficiency diseases may actually represent an obstacle to success battling chronic disease.

These days, health seems to have been reduced to a highly commercialized commodity, in which we’re marketed all sorts of high-cost, high-tech tests and treatments of dubious value with substantial risks attached. “This is worrisome because most of the things that make us healthy and keep us healthy are cheap and largely available without professional help or commercial prodding.” This isn’t to say modern medicine can’t work miracles, but what about the big picture? That is, what about the 80 percent of death and disability caused by preventable diet-related diseases?

What about the field of nutrition? In my video Why Is Nutrition So Commercialized?, I discuss how it’s become about profits and products, and extracting nutrients from whole foods so they can be repackaged and marketed. But food is best eaten whole. Eat the broccoli and the blueberries, not some broccoberry supplement. But the reason there aren’t more studies on whole foods is fairly obvious: You can’t patent them. Why should a company spend a lot of money, time, and effort to convince you to buy broccoli when any other company can sell it to you? That’s why the field of nutrition can be more about marketing profitable products than educating people about the fundamentals of health and wellness. For example, the benefits of whole grains over refined grains is commonly attributed to the fiber, which enables the food industry to whip out fiber-fortified Froot Loops and make you feel all better.

Let’s consider this ingenious study: Burkitt and colleagues thought the extraordinarily low rates of killer chronic diseases in sub-Saharan Africa were due to all the whole, plant foods they were eating. This turned into the fiber hypothesis, the reductionistic thought that fiber must be the magic bullet active ingredient. What happens if we put it to the test? What if we compared two groups of older women, both getting around six grams of grain fiber a day, but one group mostly from whole grains and the other mostly from refined grains? Who do you think lived longer? If it was just the fiber, there shouldn’t be much difference because both groups ate about the same amount. In fact, the whole grain group lived longer and with a significantly lower mortality rate, which implies that it may be all the other wonderful things in whole plant foods “linked to fiber [that] may confer important health benefits above and beyond effects of the fiber itself.” That’s why fiber supplements wouldn’t be expected to offer the same benefit.

Indeed, food, not nutrients, is the fundamental unit in nutrition.

As Dr. David Katz has pointed out, “Our culture doesn’t want to hear that the active ingredient in broccoli is broccoli—it wants to know what supplement it can take.”


This is part of my extended series on the reductionist trap, which includes:

The Five to One Fiber Rule still holds, though, since it’s an indication of how heavily processed a product is.

There are two sides to the intellectual property argument when it comes to food. I explore both in Plants as Intellectual Property: Patently Wrong?.

And, of course, this is why I always recommend Taking Personal Responsibility for Your Health.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Where Vitamin D Supplements Fail

As I discuss in my video Do Vitamin Supplements Help with Diabetes, Weight Loss, and Blood Pressure?, review articles continue to be published touting vitamin D as a veritable cure-all. The vitamin D receptor is found in most tissues in the body, including the brain, and upwards of 2,000 genes may be regulated by vitamin D. Within 24 hours of vitamin D exposure, we can change the expression of hundreds of genes.

The term vitamin is a misnomer, though, because vitamins by definition cannot be synthesized within our body, but we can make all the D we need with sufficient sun exposure. So, rather than a vitamin, D is actually a hormone that’s produced by our skin in response to sunlight exposure. D is not just a hormone of calcium regulation and bone health; it’s also a hormone of fertility, immunity, and brain function. But is it a panacea or a false prophet?

Remember when vitamin E was the vitamin du jour, touted as a “curative for many clinical disorders”? Supplement sales of vitamin E, the “radical protector,” created a billion-dollar business that capitalized on the public’s fears. After all, those with low levels of vitamin E in their blood had a 50 percent higher cancer risk. Similar attention was directed towards vitamin A or beta-carotene. People who eat lots of greens, sweet potatoes, and other beta-carotene-rich foods have lower risk of cancer, so maybe we should give people beta-carotene pills? When they were put to the test, however, beta-carotene pills actually increased cancer rates. In fact, beta-carotene, vitamin A, and vitamin E supplements all may increase mortality, so when we buy these supplements, we’re potentially paying to shorten our lifespans. As such, I imagine you can understand the skepticism in the medical community regarding claims about vitamin D, which is now enjoying its moment in the sun.

Having a half-billion-dollar vitamin D supplement industry doesn’t help matters in terms of getting at the truth. And there’s also a highly lucrative vitamin D testing industry that loves to talk about the studies suggesting that having higher vitamin D levels may reduce the risk of heart disease, cancer, diabetes, autoimmune diseases, and infections. Most of this research, however, stems from observational studies, meaning studies that correlate higher D levels in the blood with lower disease risk, but that doesn’t mean vitamin D is the cause. It’s like the early beta-carotene data: Higher levels in the blood may have just been a marker of healthy eating. Who has high beta-carotene levels? Those who eat lots of greens and sweet potatoes. Similarly, higher levels of vitamin D may just be a marker of healthy behaviors. Who has high vitamin D levels? Those who run around outside, and those who run around outside, run around outside. Indeed, higher vitamin D levels may just be a sign of higher physical activity.

So, for instance, when you see studies showing significantly lower diabetes rates among those with higher vitamin D levels, it doesn’t mean giving people vitamin D will necessarily help. You have to put it to the test.  And, when you do, vitamin D supplements fall flat on their face, showing no benefit for preventing or treating type 2 diabetes.

So, when supplement companies wave around studies suggesting vitamin D deficiency plays a role in obesity, because most population studies show that obese individuals have lower vitamin D levels in their blood, is that simply because they’re exercising less or because it’s a fat-soluble vitamin so it’s just lodged in all that fat? We might expect obese sunbathers to make more vitamin D, since they have more skin surface area, but the same exposure level for them leads to less than half the D bioavailability, because it gets socked away in the fat. This is why obese people may require a dose of vitamin D that’s two to three times higher than normal weight individuals, although they may get it back if they lose weight and release it back into their circulation. This would explain the population data. Indeed, when you put vitamin D to the test as a treatment for obesity, it doesn’t work at all.

It’s a similar story with artery health. Those with low vitamin D levels have worse coronary blood flow, more atherosclerosis, and worse artery function, but if you actually put it to the test in randomized controlled trials, the results are disappointing. Vitamin D is also ineffective in bringing down blood pressures.

This all adds to the growing body of science “casting doubt on the ability of vitamin D supplementation to influence health outcomes beyond falls, fractures, and possibly respiratory tract infection and all-cause mortality.” Wait. What? Vitamin D supplements may make you live longer? That’s kind of important, don’t you think? I talk about that in my video Will You Live Longer If You Take Vitamin D Supplements?.


Explore the other videos in my series on vitamin D, including:

And check out these other videos on vitamin D’s potential benefits:

For additional videos on supplements, see:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations: