Eating sufficient protein is a challenge for vegans. Proteins are made of amino acids, which play important roles in many of your body's functions: growth and development, building and repairing cells and tissues, making hormones and enzymes and stimulating your immune system. Few foods in a vegan diet provide all the essential amino acids needed to make a complete protein, but you may combine certain foods to obtain your protein requirements.
Vegan Diet
A vegan diet includes only plant-based foods, such as fruits, vegetables, seeds, nuts, legumes and whole grains, and it excludes dairy, eggs, fish, meat and other animal products.
People may choose a vegan diet for nutritional, religious or philosophical reasons. A vegan diet is a healthy diet provided that you obtain all of the essential amino acids for an adequate daily intake of protein.
Amino Acids
Amino acids are substances found in both plant-based foods and animal products. Twenty naturally occurring amino acids can be incorporated into human proteins. Each protein contains a sequence of amino acids, which may or may not include all 20 amino acids. Your genes determine the exact sequence of amino acids in each of the proteins your body makes. If you are deficient in a particular amino acid, then you will be unable to produce enough of the proteins that require it. Your body can make 10 amino acids called nonessential amino acids and the other 10 amino acids, called essential amino acids, must come from food. The 10 essential amino acids include arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Arginine is an essential amino acid for infants and children, but adults can make this nutrient.
Vegan Protein Foods
Vegans can obtain all the essential amino acids to make a complete protein in two ways. The first way is by eating plant-based foods that contain complete protein, such as soy and quinoa. Soybean is a legume and is among the most popular foods worldwide. Soybean is high in protein and equivalent in protein quality to animal foods. Soy foods include tofu, soy milk, tempeh and miso. Quinoa is a seed with a grainlike look and texture that contains all of the essential amino acids.
The second way is by combining foods that contain incomplete proteins but which together provide enough of the essential amino acids to complement what's lacking in the other incomplete protein-containing food. Beans, peas, seeds, nuts, grain and vegetables are sources of incomplete proteins. Complementary proteins are two or more sources of incomplete proteins which together contain all the essential amino acids in proper proportions. Complementary proteins include whole-wheat bread and peanut butter, rice and beans and beans or peas and corn.
Considerations
Amino acids from plant-based protein have the same effects on your health as amino acids from animal protein. Yet plant-based foods provide a healthier package of nutrients overall than animal products. Plant-based foods contain vitamins, minerals and fiber and usually do not contain unhealthy fats.
References
- McKinley Health Center University of Illinois at Urbana Champaign; Macronutrients: The Importance of Carbohydrate, Protein, and Fat; 2008
- The Vegetarian Resource Group; Veganism in a Nutshell; 2009
- University of Arizona; The Chemistry of Amino Acids; September 30 2003
- MedlinePlus; Soy; 2010
- Iowa State University Agricultural Marketing Resource Center; Quinoa; 2010
- Centers for Disease Control; Protein; 2009
Member Comments