Flashback Friday: Do Vegetarians Get Enough Protein?

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

The largest study in history of those eating plant-based diets recently compared the nutrient profiles of about 30,000 non-vegetarians to 20,000 vegetarians, and about 5,000 vegans, flexitarians, and no meat except fish-eaters, allowing us to finally put to rest the perennial question, “Do vegetarians get enough protein?” The average requirement is 42 grams of protein a day. Non-vegetarians get way more than they need, and so does everyone else. On average, vegetarians and vegans get 70% more protein than they need every day.

Surprising that there’s so much fuss about protein in this country when less than 3% of adults don’t make the cut—presumably folks on extreme calorie-restricted diets who just aren’t eating enough food, period. But 97% of Americans get enough protein.

There is a nutrient, though, for which 97% of Americans are deficient. Now, that’s a problem nutrient. That’s something we really have to work on. Less than 3% of Americans get even the recommended minimum adequate intake of fiber. So, the question isn’t “Where do you get your protein?” but “Where do you get your fiber?” We only get about 15 grams a day. The minimum daily requirement is 31.5, so we get less than half the minimum. If you break it down by age and gender, after studying the diets of 12,761 Americans, the percentage of men between ages 14 and 50 getting the minimum adequate intake? Zero.

“This deficit is stunning in that dietary fiber has been [protectively] associated…with the risk of diabetes, metabolic syndrome, cardiovascular disease…, obesity, and various cancers as well as…high cholesterol, blood pressure, and blood [sugars]. Therefore, it is not surprising that fiber is [now] listed as a nutrient of concern in the…Dietary Guidelines…” Protein is not.

“One problem is that most people have no idea what’s in their food; more than half of Americans think steak is a significant fiber source.”

By definition, fiber is only found in plants. There is no fiber in meat, dairy, or eggs, and little or no fiber in junk food. Therein lies the problem. Americans should be eating more beans, vegetables, fruits, whole grains—how are we doing on that? Well, 96% of Americans don’t eat the minimum recommended daily amount of beans, 96% don’t eat the measly minimum for greens. 99% don’t get enough whole grains. Look at these numbers. Nearly the entire U.S. population fails to eat enough whole plant foods. And, it’s not getting any better; a “lack of progress [that’s] disappointing.”

Even semi-vegetarians, though, make the minimum for fiber. And those eating completely plant-based diets triple the average American intake. Now, when closing the fiber gap, you’ll want to do it gradually, no more than about five extra grams of fiber a day each week, until you can work your way up.

But it’s worth it. “Plant-derived diets tend to contribute significantly less fat, saturated fat, cholesterol, and [foodborne pathogens], while at the same time offering more fiber, folate, vitamin C, and phytochemicals…all essential factors for disease prevention, and optimal health and well-being.”

And, the more whole plant foods, the better. If you compare the nutritional quality of “vegan [vs.] vegetarian, semi-vegetarian, pesco-vegetarian and omnivorous diets, traditional healthy diet-indexing systems, like compliance with the dietary guidelines, consistently indicate the most plant-based diet as “the most healthy one.”

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