Protein is one of three macronutrients our bodies need; the other two are fats and carbohydrates. Our bodies require a larger amount of these nutrients as compared to micronutrients like vitamins and minerals. Proteins are in every cell of the human body, making up the muscles that allow us to move, acting as enzymes that help us metabolize food and giving structure to our bodies.
Proteins are made up of building blocks called amino acids. There are 20 amino acids, nine of which are considered “essential”, because our bodies cannot make them. These nine amino acids must be supplied by the 3 week diet.
The other 11 amino acids are considered “non-essential”, because our bodies can make them. They’re not required in the diet.
Vegetarian Food Sources of Protein
The first question vegetarians often get is “how do you get your protein?” It is a myth that people following a vegetarian diet are likely to be deficient in protein. As long as vegetarians and vegans eat enough food to meet their calorie needs, eating enough protein should not be a problem.
Good Vegetarian and Vegan Sources of Protein
- Beans (soybeans, kidney, fava, black, turtle, navy beans etc.) (175 ml / 3/4 cup black beans – 11 grams)
- Lentils (175 ml / 3/4 cup = 13 grams)
- Tofu, tempeh and other soy protein products (150 grams / 1/3 brick firm tofu – 21 grams)
- Vegetarian meat substitutes like burgers and deli slices (1 soy patty – 18 grams)
- Vegetable patty (18 grams)
- Peanut butter and other nut butters (2 Tbsp. natural peanut butter – 7 grams)
- Nuts and seeds (¼ cup almonds – 8 grams)
- Eggs (1 large – 6 grams)
- Hummus (125 ml / 1/2 cup – 8 grams)
Remember, nearly all foods contain some protein.
- 1 slice whole wheat bread – 3 grams
- 1 packet instant oatmeal – 4 grams
- 1 cup 2% milk – 9 grams
- 1 cup soymilk (varies) – about 7 grams
Complete and Incomplete Proteins
Animal foods like meat and eggs contain all the essential amino acids (“complete” protein), but some vegetarian foods are limited in essential amino acids (“incomplete” protein). This limitation led to the idea of “complementary” proteins or protein combining. Protein combining means that different plant-based protein sources should be combined in a way that their limiting (deficient) amino acids complement each other; making a complete protein.
It is important to eat a variety of foods that provide all the essential amino acids, but it is not necessary to consciously combine proteins a single meal. The body will combine proteins over time.
Soy protein is the most complete plant protein.
Most people who live in developed countries have much more protein in their diets than is required for good health. Vegetarian and vegan diets contain enough protein, even for pregnant women and athletes.
Amount of Protein Required in the Diet
The typical meat-eating American eats 114 grams of protein per day (77 grams from animal sources). The typical lacto-ovo-vegetarian eats about 89 grams of protein per day; still well above the recommended daily intake of 56 grams.
For adults, 0.8 grams of good-quality protein per kilogram body weight per day is required. No separate recommendations are made for vegans and vegetarians, provided a healthy, varied diet is eaten.
Daily Protein Requirements Based on Body Weight
- 100 lbs. (45.5 kg) – 36.4 g protein
- 120 lbs (54.5 kg) – 43.6 g protein
- 150 lbs (68.2 kg) – 54.5 g protein
- 180 lbs (81.8 kg) – 65.5 g protein