One of the most common questions vegans get is the infamous: "But where do you get your protein?" The best answer I've heard is: "The same place super-strong gorillas, elephants, and horses get their's: from plants."
Here are some facts on protein and a plant-based diet that you may find interesting:
The plant-based diet includes a wide variety of whole foods consisting of beans, whole-grains, fruits, vegetables, nuts, and seeds, along with products made from these natural foods, such as tofu and tempeh. Those who believe plant protein is inferior to animal protein may be surprised to learn that plant proteins contain the same 22 amino acids as animal proteins.
Animal foods all contain complete protein--that is, all 22 amino acids. Complete protein in the vegan diet is found in the grain quinoa. Soybeans and products made from soybeans like tofu, tempeh, and miso, also contain complete protein.
Plant-based foods like legumes, most whole grains, fruits, vegetables, nuts, and seeds all contain protein but do not contain complete protein by themselves. However, the body forms an amino acid pool from the foods eaten throughout the day. When a vegan consumes a variety of foods eaten at breakfast, lunch, and dinner, the body can use these amino acids to make up complete protein.
The World Health Organization (WHO) recommends that men and women obtain 5% of their calories as protein. This would mean 38 grams of protein for a man burning 3000 calories a day and 29 grams for a woman using 2300 calories a day.
This quantity of protein is impossible to avoid when daily calorie needs are met by unrefined starches and vegetables. For example, rice alone would provide 71 grams of highly useable protein and white potatoes would provide 64 grams of protein.
Pregnant and lactating women require an additional 25 grams daily. Those recovering from surgery or serious injury need 20 percent of their daily caloric intake from protein. It is recommended that endurance athletes and body builders get between 12 and 20 percent of their calories from protein.
Unlike fat, protein cannot be stored. When it is consumed in excess of our needs, protein is broken down mostly by the liver, and partly by the kidneys and muscles. Consumption in excess of our needs overworks the liver and kidneys, and can cause accumulation of toxic protein byproducts.
Physicians in the United States rarely encounter patients who are deficient in protein. Deficiency is uncommon and is seen mostly in countries where serious shortages of food exist and malnutrition is prevalent.
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