Complementary proteins

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After giving the issue of complementary proteins in the vegan/vegetarian diet more thought and research, I’ve settled on this: Experts say the goal for all eaters is to get a variety of different types of (hopefully plant) foods into one’s daily diet. Ensuring you’ve hit as many food groups as you can is essential for complete nutrition.

This speaks both to the point made by Anonymous (regarding “Vegan Beware: just because it’s vegan doesn’t mean it’s sustainable”), and to that of Frances Moore Lappé, whose 1981 and ’91 revised editions of Diet for a Small Planet do recant somewhat an emphasis on complementary proteins but don’t entirely break from the idea; the timing is less important, the need for the full spectrum of amino acids is still very much important.

Many sources, including UBC, McGill and others, agree that complementary proteins are indeed necessary for the body to completely absorb and utilize the amino acids present in plant food—though, like I mention in the article mentioned above, the timing of it is less important. The goal should be to cover the spectrum of plant food sources from legumes to cereals to nuts to leafy greens.

The American Dietetic Association Position Paper on Vegetarian Diets says:

Plant protein can meet requirements when a variety of plant foods is consumed and energy needs are met. Research indicates that an assortment of plant foods eaten over the course of a day can provide all essential amino acids and ensure adequate nitrogen retention and use in healthy adults, thus complementary proteins do not need to be consumed at the same meal.

Further, health services at McGill University assert:

Most North Americans eat too much protein, not too little. Vegetarians, who tend to eat less protein than meat eaters, probably get enough. However, it is necessary for vegetarians to ensure they get “complete” protein. Protein from plant sources, unlike that from meats, contains only some of the amino acids required by the body. It is essential to obtain a complete set of these amino acids so the body can use them to “build up” human proteins such as hemoglobin and insulin. It is necessary for vegetarians to combine “complementary” foods to ensure they get a complete set of amino acids. These foods do not have to be eaten at the same sitting; they need only be consumed within a few hours of each other. Most vegetarians who always eat a variety of foods get complete proteins.

That said, there of course continue to be differing opinions on the importance of complementing your proteins, with some sources maintaining that the essential amino acids are contained in sufficient amounts in a single plant. The Vegan Society is one such proponent of this school of thought, calling protein complementing unneccessary and indeed “old fashioned.”

However, such a position seems to contradict the majority opinion that a varied diet of food sources is ultimately best for meeting one’s overall nutritional needs and reaching optimal health.

In a nutshell: To ensure your body is absorbing sufficient amino acids (the building blocks of protein), eat beans, nuts and seeds with grains, leafy greens and dairy (if that’s your thing).

Really, this isn’t just a lesson only for veg-heads; meat eaters, too, should eat a varied diet. As Michael Pollan—who, incidentally, will be speaking at UBC Farm on June 6—is often quoted as saying, “Eat food. Not too much. Mostly plants.” (Win a copy of his book In Defense of Food here.)