What is Protein Combining?

About 40 years ago, someone came up with the theory that plant-based proteins were incomplete and that vegetarians had to eat “complementary proteins” during the same meal. For example, advocates recommended eating rice and beans together, or tofu and sesame seeds. The best known cookbook based on the complementary protein principle was Frances Moore Lappé’s Diet for a Small Planet, with recipes like “Roman Rice and Beans” and “Kitchen Sink Cookies” (I loved the carrot bread recipe myself!)

What the research says

As it turns out, the complementary protein idea is a myth. Researchers disproved it decades ago, but some myths die hard. Our bodies actually maintain pools of free amino acids that can be used to do all the complementing for us. Some 90 grams of protein can be stored at any given time, and they get broken down and reassembled. Our bodies, in other words, can mix and match amino acids to whatever proportions we need.

Plant-based eaters do not need to be concerned about amino acid imbalances from plant proteins. For more information, see this video on Nutritionfacts.org.

How much protein do we need?

The Food and Nutrition Board of the Institute of Medicine, National Academy of Sciences, recommends 0.8 grams of protein per kilogram of body weight. That means that the “average” woman needs about 46 grams of protein per day and the average man, about 56.

Even most vegans get more than the recommended amount of protein every day, according to a large study conducted by Loma Linda University. For more information on this, see this post.