Protein on a Plant-Based Diet

As a nutritionist, athlete and someone who has followed a whole food plant-based diet since July 2012, I often get asked about protein. Specifically, “Where do you get your protein?”

The protein obsession dates back to the early-1800s when Francois Magendie discovered its importance in human health and physiology. Gerhard Mulder coined the term “protein” from the Greek work proteios, which means “of primary importance.” Justus von Liebig has been credited with describing protein as “the stuff of life itself.”  This protein obsession carried forward into the 1970s and 1980s when bodybuilders were moving into the mainstream and savvy marketers were pedaling protein powders, promoting them as a way to build muscle mass.

Despite this protein obsession, sadly, most people are unable to name one protein deficient disease.

How much protein do we really need? According to the National Academy of Sciences (Institutes of Medicine), the Recommended Dietary Allowance for adults is 0.8 grams of protein per kilogram of body weight each day. This works out to about 10% of total dietary calories, or 46 and 56 grams of protein daily for women and men, respectively. The only people possibly needing more than this are athletes, pregnant and lactating women, and people in critical care situations such as trauma and severe burns. Overall, the Acceptable Macronutrient Distribution Range (AMDR) for protein is between 10% to 35% of calories consumed.

Going back to the question I get asked most often about where I get my protein, the answer is, simply, from plants. Eating plants from a variety of sources including leafy greens, legumes (beans, lentils), nuts, seeds and whole grains provides plenty of protein from all essential amino acids.  Using the USDA Nutrient Database, the following represents 250 calories of various plant foods and their protein content:

Protein deficiency conditions, such as Kwashiorkor, are often associated with calorie deficient diets found in developing countries. However, people who maintain a dietary pattern high in ultra-processed foods are also at risk of protein deficiencies. For example, the meal pattern below provides 1,860 calories and 36 grams of protein (comprising less than 8% of calories consumed) which does not meet the minimum RDA for protein.

• Breakfast: 2 slices of bacon, 1 buttermilk biscuit with jam, coffee
• Lunch: 1 corndog, 1oz sour cream & onion potato chips, 16oz cola and 6 cream sandwich cookies
• Dinner: 1 ham & cheese hot pocket, 16oz sweet tea and 1 popsicle

On the other hand, most people who promote the Standard American Diet (SAD) and high protein diets are also unaware of the consequences of too much protein.

People who regularly consume a diet high in protein (above AMDR of 35% of total calories) may be at risk for kidney disease, bone loss, elevated cholesterol and other metabolic conditions. Also, since animal protein contains zero fiber, these high-protein dietary patterns may also be fiber deficient. Given fiber is only found in plant foods and the average person in the United States consumes 16 grams compared to the recommended 25 to 38 grams per day, perhaps the more pertinent question to ask is “Where do you get your fiber?”

In summary, eating a varied whole food plant-based diet can provide sufficient protein for all life stages.