Plant-Based Nutrition

Eating a plant-based vegetarian or vegan diet can be a healthy, exciting alternative to traditional meat-based meal planning. Obtaining proper nutrients from non-animal sources is simple for the modern herbivore. There is a wide variety of vegetarian/vegan-friendly meat/dairy/egg replacements currently on the market. Recipes are abundant on the Internet as well as in a variety of vegetarian cookbooks.

Benefits of a plant-based diet

There really are no disadvantages to a herbivorous diet! A plant-based diet has many health benefits, including lowering the risk for heart disease, hypertension, Type 2 diabetes, and cancer. It can also help lower cholesterol and blood pressure levels, plus maintain weight and bone health.

Vegetarians can be classified into 3 groups:

  • Vegans: exclude all animal products, such as meat, poultry, fish, eggs, dairy, and honey.
  • Lacto-vegetarians: exclude meat, poultry, fish, and eggs, but do include dairy products.
  • Lacto-ovo-vegetarians: exclude meat, poultry, and fish but do include eggs and dairy products. Most vegetarians in America fall into this category.

How many Americans are vegetarian?

A 2008 study published in Vegetarian Times entitled “Vegetarianism in America” shows that 3.2% of U.S. adults, or 7.3 million people, follow a vegetarian diet. Approximately 0.5%, or 1 million, of those are vegans. In addition, 10% of adults in America, or 22.8 million people, say they largely follow a vegetarian-inclined diet.

Does a vegetarian diet provide all the necessary nutrients?

If a vegetarian diet is well-planned and balanced, it can be just as nutritious, if not more beneficial to health, than a traditional diet. Obtaining the nutrients listed below from plant, rather than animal foods, eliminates much of the saturated fat and cholesterol found in a meat-based diet.


Typically, the first question people pose to a vegetarian is “How do you get enough protein?” Protein is readily bio-available in most plant as well as animal foods. Vegetarians do not need to combine specific foods within a meal to assimilate a complete protein from separate amino acid chains, as once thought. Plant foods rich in protein include nuts, seeds, legumes, lentils, tempeh, seitan, tofu, and a variety of prepared soy and wheat gluten (the protein portion of wheat) foods available in grocery and health food stores.


Lacto-vegetarians and lacto-ovo-vegetarians are able to consume dairy products rich in calcium. Vegans can obtain their calcium from plant foods such as dark, leafy greens, bok choy, kale, broccoli, tofu prepared with calcium, almonds, blackstrap molasses, and calcium-fortified cereals and juices. The bio-availability, or absorption rate, of calcium from plant sources is twice as efficient as the calcium in cow’s milk.


Good sources of non-heme iron (type of iron found in plant foods) include dark, leafy greens, dried legumes and lentils, soybeans, blackstrap molasses, and spinach. Iron absorption is improved by six-fold when eaten with a Vitamin C source. For example, vegetarian chili, including beans and tomato, is a highly bioavailable source of iron. Fortunately, many vegetables, such as broccoli and bok choy, which are high in iron, are also high in Vitamin C, so that the iron in these foods is very well absorbed.

Vitamin B-12

Is the only vitamin that cannot be found plentifully in plant foods. Lacto-vegetarians and lacto-ovo vegetarians need not worry about consuming enough B-12 if they are eating dairy and eggs on a daily basis. The concern rests with vegans, who can obtain B-12 from fortified cereals and soy milk, or from nutritional yeast, which has a pleasant cheesy flavor and can be used in recipes as a cheese substitute. To be on the safe side, many vegans take a vegan-specific multivitamin supplement with at least 2.4 mcg B-12 per day.

Vitamin D

Few foods are naturally high in Vitamin D, which is why milk is fortified (making the risk of a Vitamin D deficiency a non-issue for lacto-vegetarians). Vegans can obtain Vitamin D from 20 minutes of direct (unprotected) midday sunlight, or from a supplement.

Last reviewed by a Cleveland Clinic medical professional on 01/11/2019.

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