Do Vegetarians Get Enough Protein?

This question has been asked many times without a clear consensus on what the answer is.

Until now.

The happy herbivore writes an important paragraph:

Let me start by saying all whole foods contain protein — even kale and bananas. Sure some whole foods have more protein calorie for calorie than others, but if it a whole food, it has some protein, which means as long as you eat enough calories (and those calories come from whole foods), you aren’t going to be protein deficient 

It’s a good post. Read the whole thing.

The notion that vegetarian diets put you at risk of insufficient protein intake is a canary that refuses to die. It’s false, for the reasons mentioned above. The average person needs about 50g of protein per day, which isn’t that hard to get…..from anywhere.

A similar claim is that carnivore diets are superior because the protein contained in animal foods is more complete (bigger array of amino acids), thus more beneficial.

In a technical sense, this is true because animal proteins tend to have the amino acids lysine, methionine, and threonine in greater quantities than vegetable proteins. However, all protein gets broken down into its amino acid constituents when digested, so the particular amino acid profile of one particular food isn’t important as long as the sum of all food eaten gives you the protein that you need. And you need about 50 g. Not that much.

For the most part, vegetarian diets rarely lack any essential nutrients. My favorite example of this effect comes from a study that examined the iron, folate, and vitamin B status of vegetarian Buddhist nuns in Korea compared to their non-vegetarian counterparts. From the abstract: (emphasis added by me):

Three-day dietary records were completed, and the blood samples were collected for analyzing a complete blood count, and serum levels of ferritin, folate, and vitamin B-12. There was no difference in hemoglobin among the diet groups. The serum ferritin and hematocrit levels of vegetarians did not differ from that of non- vegetarian students with a high intake of animal source food but low intake of vitamin C, and the levels were lower than that of non-vegetarian Catholic nuns with a modest consumption of animal source food and a high intake of vitamin C. The serum vitamin B-12 levels of all subjects except one vegetarian and the serum folate levels of all subjects except one non-vegetarian student fell within a normal range.

So, if you’re on the fence about eating a plant-based diet…..don’t let that stop you.