Medically Reviewed by
Dr. Carla Montrond Correia ND, CNS
8 min read
Protein is an essential part of any diet. Although it is mainly found in animal-based products, vegetarians and vegans have options, too. Keep reading to learn more.
Protein makes up the majority of the structures in the human body. An essential part of any diet, this macronutrient breaks down into amino acids that the body uses as fuel for energy, building muscle, and the structure, function, and regulation of its organs and tissues. It can be found in many foods such as meat, poultry, seafood, eggs, dairy, legumes, nuts, and seeds.
Generally speaking, animal-based protein foods provide adequate amounts of all nine essential amino acids. Plant foods, whole grains, nuts, and seeds, on the other hand, possess high levels of some amino acids and low levels of others. Vegetarians and vegans needn’t be alarmed, however, since the proper combination of plant-based foods can provide similar benefits to those derived from animal-based proteins.
Protein plays a key role in the creation and maintenance of every cell in the body. It also fuels these cells so that you have sufficient energy to stay active. The essential macronutrient builds muscle, maintains muscle mass, helps stabilize the body’s blood sugar level, plays a role in hormone regulation, and maintains satiety.
NHANES data suggests that vegetarians and vegans have a higher prevalence of protein inadequacy than meat-eaters and that vegetarian and vegan adults may require increased protein intake as they age. The good news is that studies have demonstrated that a well-planned, plant-based diet can provide similar benefits to a diet with proteins from animal sources.
Whey protein is considered to be a complete source of protein, which means it contains all of the essential amino acids. It is also high in branched-chain amino acids, which are important to maintain muscle and necessary to replenish after exercise. The downside of whey protein is that it is derived from milk so not suitable for vegans or anyone who prefers to be non-dairy. Ideally you would want your whey from grass-fed cows and with a protein concentration of 90-95% and lactose and fat content of 0.5-1%.
Soy protein is derived from soybean, the legume so central to the diet of China that it’s simply referred to as “the great legume” or “the yellow legume” (though not all soybeans are yellow). It is native to Manchuria (north-east China) and, though initially discovered nearly 3,000 years ago, it took about 1,000 years for its nutritional value to be understood. Since the 1960s, soybean products have become a staple in many American homes, especially those following vegan and vegetarian diets.
Soy-based foods are unique because they are flavorless, provide all nine essential amino acids in sufficient quantities, have plant-based estrogen properties, and are available in a wide variety of “meat-like” foods. Whether it’s a tofu product, soy milk, tempeh, miso, or any other soy processed food, it’s always best to stick to organic sources.
Pea protein is usually made from yellow peas. It is gluten-free, dairy free, nutritious, and of low allergenicity. Though it contains all 9 essential amino acids and is a good source of iron, arginine and Branch-Chain Amino Acids (BCAAs), pea protein is low in methionine, an essential amino acid that cannot be made by the body.
Rice protein%20content%20%5B12%5D. "Rice protein") is an excellent source of protein, though both brown and white rice are low in lysine and high in methionine. The good news is that beans are high in lysine and low in methionine. Together, rice and beans contain all nine essential amino acids forming a complete source of protein. Top the mixture off with some salsa, guacamole, and vegetables for a healthy, filling, easy meal.
Though Chia seed protein is highly nutritious and loaded with antioxidants, it is not a complete source of protein. It is, however, an excellent source of omega-3s and fiber, and rich in minerals like phosphorus, calcium, potassium, and magnesium. Chia seed protein makes an especially healthy addition to any smoothie.
Hemp seed protein is a complete protein, (containing all of the essential amino acids), rich in fatty acids, fiber, and essential minerals like iron and potassium. Though it comes from the hemp plant Cannabis sativa and its seeds are members of the same species as marijuana, you will not get high. You will, however, have found a healthy, delicious, nutty addition to yogurt, smoothies, and even your salad.
Eggs are a complete amino acid profile food that contain 6 grams of protein per large egg. They are also rich in vitamin D, Omega 3s, antioxidants, and choline. They are versatile, compact, and you already know how to make them.
Yogurt, especially thicker Greek yogurt, is high in protein, calcium, vitamin B12, and several key minerals. Fat-free yogurt is made from skim milk and all other yogurt from whole milk. It is not recommended for those with milk allergies (casein or whey), and is not suitable for dairy free or vegan diets. Choose your yogurt carefully as many commercial brands contain sugar and other additives. Try plain, unsweetened yogurt with fresh berries, nuts and seeds for a delicious breakfast or mid-day snack.
Beans and legumes are packed with protein, high in fiber, contain phytochemical properties that work as antioxidants, and, when properly prepared, have more potassium than a banana. They are also low in fat and nearly free of saturated fat. While beans are not a complete protein, when combined with rice, the dish has all the amino acids of a complete protein. Popular beans and legumes include peanuts, lentils, black beans, kidney beans, cannellini beans, soybeans, and chickpeas. Whether it’s hummus, lentil soup, or any of the countless recipes out there, the fact is beans and legumes are an inexpensive protein source with extraordinary possibilities for healthy, delicious, plant-based fare.
Though technically an edible seed, Quinoa is classified as a whole grain. It is high in fiber and rich in magnesium, phosphate, thiamine, folate, and manganese. Unlike most plant-based proteins, it is a complete protein.
Nuts and seeds are healthy sources of plant-based protein that make convenient snacks and are easy additions to any dish if you’re looking to boost its protein content. While peanuts provide the most protein per serving, commercial peanut butters often contain added sugars, fats, and oils. Look for organic, whole peanut butter, or try making it yourself. Other healthy, delicious nuts include almonds, cashews, walnuts, hazelnuts and Brazil nuts.
Vegetarians and vegans are at a higher risk for vitamin b12 deficiency as it is commonly found in animal products but not present in fruits or vegetables. Older adults are also prone to this deficiency as they have difficulty absorbing it. Active forms of b12 (methylcobalamin, hydroxocobalmin, and adenosylcobalamin) are the most easily absorbed.
Vitamin D is a fat-soluble vitamin that can be synthesized from sun exposure or obtained from the diet. There are two types of vitamin D: D2 (ergocalciferol) and D3 (cholecalciferol). Vitamin D2 is synthesized by plants and not produced by the human body. On the other hand, vitamin D3 is produced by the human body from sun exposure, when conditions permit, and can be consumed from limited food sources such as fortified milk, egg yolks, meat and fatty fish such as sardines or mackerel.
Calcium is a mineral that is necessary for building bones and keeping them healthy, enabling our blood to clot, our muscles to contract, and our hearts to beat. Every day, we lose calcium through our skin, nails, hair, sweat, urine, and feces. Our bodies cannot produce its own calcium but it can be found in dairy, fortified plant-based milks (soy, almond, rice), fortified orange juice, edamame, and leafy greens.
Studies have proven that a well-balanced vegetarian diet can yield a satisfactory iron level. Iron from food comes in two forms: heme and non-heme. Heme is found in animal meat while non-heme is found in plant-based foods, leafy greens, whole grains, nuts, seeds, and legumes. Vitamin C can help with better absorption.
Iodine is a trace mineral that is not made by the body so it must be found in food or supplements. Some excellent sources of iron are seaweed, kelp, fish, “iodized” table salt, dairy, eggs, and chicken.
Omega-3 fatty acids are essential fats that the body cannot make so they must come from food. Fish oil, fatty fish (salmon, trout, mackerel), walnuts, flaxseed, flaxseed oil, and leafy greens are especially good sources of Omega-3 fatty acids. Algae oil can provide an alternative to fish oil.
Zinc is a trace mineral that is responsible for approximately 100 enzymatic reactions in the body. It is responsible for wound healing, DNA synthesis, immune function, protein absorption and cell division. Since the body cannot produce zinc on its own, it must come from food sources. Oysters, crab, lobster, red meat, whole grains, legumes, nuts, and seeds are all excellent sources of zinc, though legumes and whole grains contain phytates that can lower its absorption.