Significance of "Complete Protein" in a Vegetarian Diet
Expand your culinary horizon beyond the conventional 3-course paradigm of animal protein plus starch plus vegetable. Vegetarian meals typically combine several different kinds of incomplete protein to obtain a complete balanced protein. Look to indigenous cultures and traditional peasant cuisines for delicious protein combinations: Mexican, Indian, Thai, Chinese, Mediterranean, Middle-Eastern, Native American, etc.
All proteins are composed of several different kinds of amino acids. While there are dozens of amino acids, eight of these are classified as essential because our bodies cannot build them from other components; they must be supplied by our diet. People who eat animal products are likely to get complete protein without any special effort. Vegetarians need to combine different sources of incomplete protein in appropriate ratios.
The Centers for Disease Control and Prevention defines complementary proteins as two or more incomplete protein sources that - when combined - provide adequate amounts of all the essential amino acids. Examples include grains plus legumes; and legumes plus seeds plus nuts. See https://www.reference.com/health/complementary-proteins-c8b60f574f85a10b .
A vegetarian diet should include a variety of foods with complementary proteins so that the essential amino acids missing from one protein source are supplied by another. Most non-animal protein sources (aside from soybeans) lack one or more of the essential amino acids that are needed for proper body functioning. Legumes such as lentils, beans and peas lack the amino acids methionine and tryptophan, while whole grains such as brown rice, oats and wheat lack the amino acids isoleucine and lysine. Combining these two food groups yields complete proteins with the full range of essential amino acids.
It is not necessary to eat complementary proteins together at each meal (although numerous cultures do combine these foods in meals such as corn and beans, falafel and pita, or rice and lentils). Food combinations for vegetarians and vegans include dairy plus grains, dairy plus seeds, dairy plus legumes, grains plus seeds, grains plus legumes, and legumes plus seeds.
To the person accustomed to eating meat, vegetarian food can seem strange or boring at first, and it may feel filling in a different way. Your body will quickly become accustomed to it as your population of beneficial gut organisms adapt to help you digest different kinds of food.
A variety of fresh ingredients, appropriate and varied herbs and spices, and attractive presentation can all enhance the vegetarian experience.
Go ahead and add something green when appropriate, if you have it: a handful of fresh herbs, or a garnish of chopped cilantro, parsley, scallions, chives or onion leaves. Little additions can freshen up an often-used recipe, and improve its nutritional content.