A vegan diet prohibits all animal products, even eggs and milk, which many vegetarian diets allow as they are normal parts of animal and bird life. Because of this, a strict vegan diet may lack some parts of nutrition that are most efficiently consumed through meat or eggs; essential amino acids, which are protein, are most available through meat and less so through vegetables and fruits. Amino acids are essential for healing, growth, and general good health.
To provide a properly balanced amino acid intake, the vegan diet should contain at least 1.4 grams of protein for every kilogram of body weight; women should consume about ten grams less total than men. A healthy man weighing 68kg should consume at least 55 grams of protein daily. This protein can be found in many vegetables, but in lesser quantities than in eggs or meat; while meat and eggs are complete proteins, meaning that they contain all the essential amino acids, most vegetables contain incomplete proteins. However, by eating a wide variety of plants including nuts, fruits, beans, and vegetables, the body will store and regulate proper amino acid levels. One of the only plants that has a complete amino acid profile is the soybean; soybean-based foods are very healthy, as they contain protein and fiber in high quantities compared to other plants, as well as good fats.
Essentially, a varied diet with daily servings of soybean products should provide all the amino acids necessary for a healthy diet. Contrary to popular belief, there is little chance of protein starvation on vegan diets unless the diet is restricted to only a few types of food.
A (healthy) vegan diet provides the proper amount of amino acids needed for the body through complete proteins. As the person above stated, soy beans are one of the foods that provides a complete protein. This is why many "Fake Meat" products are made with soy and why tofu is associated most with vegans/vegetarians (tofu is made from soybeans).
There are vegans that are allergic to soy and still get all the essential amino acids needed through, once again, complete proteins. These are through combinations of food to create complimentary proteins. They do not have to be eaten together, just as long as these foods are eaten within the same day. Some complimentary protein combinations include:
- Black beans and rice
- Pasta and peas
- Whole wheat bread and peanut butter
- Bean soup and crackers
- Roasted nuts, seeds and peanuts
- Hummus (chickpeas and tahini)
- Lentils and almonds
As long as there are enough complete or complimentary proteins eaten throughout the day, a vegan can get all the amino acids needed.