Protein Revisited

I was hiking with a friend recently, and we were discussing the possibility of his adopting a plant-based diet when he raised the concern of not getting enough protein. Really? I thought that notion had been put to bed, but apparently, it is still with us.

In fact, this idea is a myth that was unknowingly created by Francis Lappe in her book “Diet for a Small Planet” 40 years ago. She later admitted that she made a mistake and retracted her original statement. But the meat and dairy industry jumped on it, and have used that false myth to create a marketing campaign to sell their products. Their message is that without copious amounts of animal protein, it’s impossible to be healthy, let alone perform as an athlete. And this message is EVERYWHERE: ad campaigns, compelling food labels, testimonials from fitness experts, etc. Protein, protein, protein – generally reinforced with the adage that more is better. So, it is now engrained in our collective psyche.

No wonder my friend was concerned. We’ve all been willfully misled by industry advertising for decades. No wonder the number one question asked of most vegans is “where do you get your protein?” That’s all due to marketing hype; on the flip side, there is reality. The surprising news is that over 97% of all Americans exceed the minimum daily requirements for protein. Even vegans exceed the RDA by 70%.[1] The RDA for protein is about 0.36 grams per pound of body weight for adult men and women. So, for a 170–pound individual, that’s 61.2 grams of protein per day. The average American male consumes about 102 grams of protein per day; the average American female consumes about 70 grams of protein.

The RDA of protein equates to about 8–10% of total dietary calories. Note that the minimum amount of protein required for the average adult is much less, around 4–5%. By setting the RDA to the higher amount, the USDA provides a buffer that ensures that about 98% of the population will get more protein than actually needed.[2]

Clearly, protein deficiency is not a pressing health issue in America. So, it is amazing that so many people are obsessed about consuming protein, as if they can’t get enough. I suppose that’s a testament to the effective marketing tactics used by the purveyors of protein. If people examine the matter a bit more closely, they might revise their opinion. Consider John Robbins’ book, Healthy at 100, which describes the diets and habits of four very different cultures that produce some of the world’s healthiest and most long–lived people on the planet. There are several factors for the longevity and vigor of these populations, including regular physical activity, stress reduction, and engagement in family life. The common thread in their diets is that they all eat low protein, high nutrient diets.[3] Let that sink in. The healthiest people on the planet eat low protein diets. So, cramming the maximum amount of protein into your system isn’t necessary, and it definitely isn’t desirable, especially if you want to live a long and healthy life. In fact, excess protein has been linked with osteoporosis, kidney disease, calcium stones in the urinary tract, and some cancers.[4] A long-term study published in 2014 found that diets rich in animal protein are linked to a fivefold increase in risk of death from diabetes and a fourfold increase in risk of death from cancer. Our bodies need protein, but moderate amounts will do nicely.

And the source of protein is critical. A recent large–scale study showed that high animal protein intake was positively associated with cardiovascular mortality while high plant protein was associated with reduced all–cause mortality and cardiovascular mortality.[5] In fact, Dr. T. Colin Campbell, in his book The China Study, states “dietary protein within the range of 10 to 20% is associated with a broad array of health problems (e.g. higher blood cholesterol levels, higher risks of cancer, osteoporosis, Alzheimer’s disease, and kidney stones), especially when most of the protein is from animal sources.”

In his article “A Fallacious, Faulty and Foolish Discussion About Saturated Fat,” Campbell explains that heart disease is not caused by a single dietary factor such as saturated fat or a single clinical factor such as LDL cholesterol. Rather it is a complex sequence of events that is dependent on the consumption of animal–based protein. “It is far more important to focus on the avoidance of animal–based foods—and concocted ‘foods’ of plant parts—in favor of whole plant–based foods naturally low in fat and protein.”[6]

Your daily protein requirement is readily obtainable from plant sources because plants contain a surprising amount of protein. The average green leafy vegetable has about 35–51% of its calories from protein. Other vegetables tend to be around 25% protein. Whole grains can range from 14% to 18% protein. Beans are around 25% to 27% protein. Fruits contain less protein, around 5% to 6%. So, if your goal is to consume between 6% and 10% protein, you can see that almost any combination of plant food sources will easily supply that. As Alan Goldhamer put it, “All natural foods-from lettuce to nuts contain varying amounts of protein. If a varied diet sufficient in calories is consumed, it is virtually impossible to get an inadequate protein intake.” T. Colin Campbell states “You can’t be protein deficient without being calorie deficient.” He notes that even the foods that have the least amount of protein in them (potatoes or rice) have 8 or 9% protein, which is what our bodies need.

The good news is that you don’t need to obsessively mix and match plants in an elaborate production effort to assemble the perfect protein. And you don’t need to eat every essential amino acid at every meal. Your body does it all for you. It stores and recycles amino acids. Every plant that contains protein, including vegetables, grains, legumes, nuts, and seeds, provides the body with amino acids. Eating a variety of plant foods provides all of the essential amino acids that we humans need. Your body breaks down protein from food sources into individual amino acid building blocks, and then reassembles them into proteins as needed. Even though some plants contain higher percentages of certain amino acids than others, as long as you consume protein from a variety of plants, your body can make as much protein as it requires. Of course, if you are aren’t getting enough calories or eating all fruit, or eating large amounts of highly processed foods, all bets are off.

So, if you know anyone who is concerned about getting enough protein on a plant-based diet, feel free to share this post with them. I’ve included a few references below to support the discussion points.

1. Greger, Michael, MD, “Where Do You Get Your Fiber?” Nutritionfacts.org,

http://nutritionfacts.org/2015/09/29/where–do–you–get–your–fiber/.

2. Karlsen, Micaela, MSPH, “How Much Protein Do We Need? RDA vs. Dietary Guidelines,” Center for Nutrition Studies, http://nutritionstudies.org/how–much–protein–do–we–need–rda–vs–dietary–guidelines/

3. Robbins, John. Healthy at 100: The Scientifically Proven Secrets of the World’s Healthiest and Longest Lived Peoples. Ballantine Books, 2007.

4. Physicians Committee for Responsible Medicine, “The Protein Myth,” PCRM.org,

http://www.pcrm.org/health/diets/vsk/vegetarian–starter–kit–protein.

5. Song, Mingyang, MD, ScD; Teresa T. Fung, ScD; Frank B. Hu, MD, PhD; et al., “Association of Animal and Plant Protein Intake With All–Cause and Cause–Specific Mortality,” JAMA Internal Medicine (2016); 176(10): 1453–1463.

http://jamanetwork.com/journals/jamainternalmedicine/article–abstract/2540540.

6. Campbell, T. Colin, PhD, “A Fallacious, Faulty and Foolish Discussion About Saturated Fat,” Center for Nutrition Studies, http://nutritionstudies.org/fallacious–faulty–foolish–discussion–about–saturated–fat/.

To your health!

David Kater