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Getting the Most From a Vegetarian or Vegan Diet

Feb 26, 2014 ● By Katherine Chavez, ND

Vegetarian and vegan diets are associated with many health benefits, but the quality of the diet is very important; just taking out animal foods is not enough and can in fact increase some nutrient deficits. Some basic guidelines and monitoring with routine blood work can ensure optional nutrient intake to easily avoid these deficiencies.

Studies show many benefits of avoiding animal foods whether just meat for vegetarians or all animal products, including milk, eggs and sometimes yeasts and honey for vegans. Studies show that vegetarians have lower risk of mortality by all causes, including a 29 percent decreased risk of dying of heart disease. They have lower levels of LDL or “bad” cholesterol and diabetes, and lower body weight.

Vegetarians have lower risk of all cancers by 18 percent, especially colon cancer. These benefits are not only due to reduced consumption of animal foods, but also, in a well-balanced vegetarian diet, higher content of fiber, unsaturated fats, phytochemicals and plant pigments, potassium, magnesium, folate and vitamins A, C and E.

In addition to health benefits to the individual, there are other advantages to a vegetarian diet. Animal husbandry uses more natural resources and produces more waste for less food gained. This model of food production is more likely to contribute to long-term environmental degradation and food insecurity.

Eliminating all animal products from the diet does have its challenges, because they are indisputably a great source of complete protein, EPA and DHA omega-3 fatty acids and iron. These challenges can be managed by making conscientious food choices and in some cases, with supplementation.

Complete proteins are defined as proteins that contain all nine essential amino acids: phenylalanine, valine,  threonine, tryptophan, methionine, leucine, isoleucine, lysine and histidine. All animal foods contain all of these amino acids. Several plant foods comprise complete proteins: quinoa, soy, hemp seeds, amaranth, buckwheat, chia, aphanizomenon flos-aquae (blue green algae) and spirulina.

While some of these foods are a bit exotic and may not be readily incorporated into a typical meal, many are very easy to incorporate into almost any diet. All other plant proteins are incomplete, and do not contain either lysine or methionine. However, incomplete plant proteins can become complete by combining with other foods.

For instance, in the classic vegetarian meal of rice and beans, rice does not contain lysine and beans do not contain methionine, but when eaten together, they are a complete protein. Other plant foods that do not contain lysine include corn, barley, buckwheat, oats, rye and wheat. Combining these with beans, which are rich in lysine but deficient in methionine, will make a complete protein.

Omega-3 fatty acid deficiency is not unique to vegetarians and vegans, but is more of a challenge. Wild-caught cold-water fish such as salmon, anchovies, sardines and tuna are the richest foods in the omega-3 fatty acids called EPA and DHA. Grass-fed, free-range animal meat, milk, eggs and the meat of wild game like deer or elk also have some EPA and DHA. Plant foods like flax seeds, walnuts and algae are also great sources of ALA omega-3 fatty acids.

Our bodies can convert some ALA to EPA and then DHA, but only between 6 percent and 3 percent, respectively. Accordingly, vegetarians should make sure to eat free-range eggs and milk, and both vegetarians and vegans should get plenty of flax and walnuts. Both groups, especially vegans, should also take an algae-based DHA and EPA supplement of about 1,000 mg to make sure they are getting adequate levels of this vital nutrient.

Vegetarian Vegan DietWhile there are many plant foods that are rich in iron, plant sources are not the right form of heme iron and are not well absorbed. Eating iron foods with vitamin C will increase absorption. Iron-containing plant foods are pumpkin seeds, blackstrap molasses, beans, spinach and for vegetarians, egg yolk.

Eat these with high vitamin C-containing foods like peppers, guava, thyme and parsley, kale, kiwi, broccoli, Brussels sprouts, mustard greens, papaya, strawberries and oranges, in that order. It is true that oranges are not the highest on the list of vitamin C-containing foods, despite the citrus industry’s educational efforts.

Another easy way to greatly enhance the iron content of our food is to cook in a cast iron skillet, especially vitamin C-containing foods, because they will draw more iron from the skillet. Testing blood iron levels and iron stores called ferritin is important for vegetarians, especially menstruating vegetarian, because losing iron each month with menstrual blood greatly increases risk of deficiency.

Vitamin B12 is found almost exclusively in animal foods. Vegetarians can consume some B12 in egg yolks and yeast-containing foods like nutritional yeast and the fermented beverage Kombucha. Because yeasts are arguably an acceptable vegan food, some vegans will not be able to get B12 from their diet at all. B12 supplementation is always vital for vegans and almost always vital for vegetarians. Vitamin B12 levels can also easily be measured with blood work. Vegans and vegetarians should have their levels measured annually.


Dr. Katherine Chavez, ND is on the staff of the Raby Institute, 500 North Michigan Ave., Chicago. She is certified as a Doctor of Naturopathic Medicine by the North American Board of Naturopathic Examiners and is a candidate fellow of the American Board of Naturopathic Oncology. To schedule an appointment with Dr. Chavez, call 312-276-1212.