Vegetarian Diet: Types and Nutritional Considerations
Vegetarian diets are followed by many people around the globe for varied reasons such as health issues, religious belief or in an attempt to preserve and protect animal rights.
These diets vary depending upon the degree of avoidance of animal-origin foods. The strictest vegan vegetarian diet consists primarily of cereals, vegetables, fruits, legumes, and nuts. This type of diet usually excludes any product of animal-origin such as eggs, milk, and other dairy products. Many less restrictive vegetarian diets may include animal flesh, eggs, or milk and milk products.
- Semi-vegetarian: These people may include meat, fish or chicken in their diet occasionally. They avoid red meat completely, but eat fish and perhaps chicken.
- Pescetarians: Vegetarians who include fish in their diet occasionally, along with egg, milk, and milk products, but who avoid chicken, beef, or red meat.
- Lacto-ovovarians/pollo vegetarian: Include eggs, milk and milk products in the diet and avoid any animal meat, chicken, fish.
- Lacto-vegetarians: These people take milk and milk products in their diet. Such vegetarians avoid eggs and meats.
- Macrobiotic: Whole grains are especially included, along with vegetables, legumes, and seaweed, in the daily food. Animal-origin foods are limited to white meat or white meat fish. Locally grown foods are usually recommended.
- Vegans: All animal products are excluded from the diet including eggs, milk, and milk products. Additionally, some vegans may exclude honey, foods that are processed or not grown organically or ingredients derived from animal-origin such as gelatin and casein.
- Fruitarians: Includes only fruits, nuts and seeds. Vegetables that are botanically considered fruits are included in such diets. All other vegetables, grains, beans and animal products are excluded.
- Raw vegan: This diet includes unprocessed food that is heated above 115 degrees Fahrenheit. Although the people following this diet prefer no cooking, they sometimes process such as by blending. This type of diet is usually followed for health reasons.
- Kangatarian: All meats are excluded from the diet except kangaroo. It is believed that the animal is killed humanely as it dies instantly. It is said that kangaroo is the animal of choice for those who exclusively eat organic meat.
Is Your Diet Nutritionally Adequate?
The nutritional adequacy of a vegetarian diet is judged on the basis of the type, amount, and variety of nutrients that are consumed.
Vegetarian diets often have a number of health advantages, including lower blood cholesterol, lower risk of heart diseases, hypertension and type 2 diabetes. Additionally, these diets are high in dietary fibers, vitamin C and E, magnesium, potassium, carotenoids, and flavonoids. However, lower intake of some other nutrients such as calcium, vitamin D, and B12 may be seen in some vegetarians whose diet is not varied and well-balanced.
Here are some important nutrients that are needed to be balanced to make the best of your diet.
Typical protein intakes of lacto-ovo-vegetarians and of vegans usually meet and exceed the requirements. Not surprisingly, even athletes can meet their protein needs on vegetarian diets.
Protein and energy requirements are usually met if a variety of plant foods are consumed over the course of the day. And in this case, complementary proteins are not usually needed at the same meal.
While vegetarian foods can provide all essential amino acids and ensure nitrogen absorption, protein requirements for individuals may vary depending on the dietary choices.
For example, eating wheat protein alone can result in reduced efficiency of nitrogen utilization, whereas soy protein can be as effective as meat protein.
Sometimes adjustments of the diet will be needed. Such as cereals that are low in lysine, an essential amino acid, can be followed by eating more of beans and soy products that are a good lysine source.
N-3 Fatty Acids
Fatty acids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are important in cardiovascular health as well as eye and brain development.
Diets that exclude fish, eggs, and algae are generally low in these types of fatty acids. This is why vegetarians particularly vegans have lower levels of DHA and EPA in the blood compared to non-vegetarians.
Pregnant and lactating women require high levels of DHA and this can be met by taking DHA-rich microalgae.
Flaxseed, walnuts, canola oil, and soy are rich sources of ALA (that converts to DHA). Soy milk and breakfast bars fortified with DHA are also available in the market.
Iron and Zinc
Phytates, calcium, tea, coffee, and cocoa can inhibit iron and zinc absorption. Some food preparation techniques such as some fermentation processes or soaking and sprouting beans, grains and seeds can enhance the iron and zinc levels in the body by diminishing phytates.
Iron from plant foods is non-heme iron that is sensitive to inhibitors as well as an enhancer of iron absorption. Because of low iron availability in the blood from a vegetarian diet, vegetarians are encouraged to take iron 1.8 times those of non-vegetarians.
Zinc may also be needed more than the recommended dietary allowance (RDA) amount. Soy products, legumes, grains, cheese, and nuts are good sources of zinc.
Plant foods are typically low in iodine. Hence, those vegans who do not consume iodine rich sources, such as iodised salt or sea vegetables, may be at a risk of iron deficiency.
Note: Sea salt, kosher salt, salty seasonings such as tamari are not iodized. If you are consuming sea sources check their iodine content as these are not usually adequate in iodine.
A lacto-ovo vegetarian diet offers calcium similar to and sometimes greater than a non-vegetarian diet. But vegan diets may have lower than the recommended amount.
Foods with good calcium bioavailability are:
- Low-oxalate greens. (eg, bok choy, broccoli, Chinese cabbage, collards, and kale)
- Calcium-set tofu, cow’s milk, sesame seeds, almonds, and dried beans.
- Fortified foods such as calcium-citrate and malate fruit juices, soy milk, and rice milk, and breakfast cereals.
Vitamin D plays a role in bone health. Its level depends on sunlight exposure and the intake of vitamin D-fortified foods and supplements. Sometimes, vitamin D2 and D3 are also used to fortify foods. Vitamin D3 is produced in animals and vitamin D2 in yeast by UV irradiation. Vitamin D2 is usually acceptable to vegans.
Vitamin D fortified foods are:
- Cows milk, rice milk, orange juice, some brands of soy milk, breakfast cereals, and margarine.
No plant food contains enough amounts of Vitamin B12. Thus, vegans need to get the dietary recommended amounts from fortified foods such as fortified soy and rice beverages and breakfast cereals. However, lacto-ovo vegetarians can get enough amount from eggs or dairy foods.
Most plant foods contain folacin, which may mask the deficiency symptoms of vitamin B12 so that the deficiency may go undetected until after the neurological symptoms manifest.
Vegetarian Diets Are Healthy
Well planned vegetarian diets are appropriate for infants, children, adolescents and pregnant or nursing women. It may promote normal growth of infants and children.
More often, the children who grow up on a vegetarian diet establish healthy eating patterns lifelong and this can give them the added nutritional benefits compared to non-vegetarians
Which type are you?
- Craig WJ, Mangels AR, American Dietetic Association. Position of the American Dietetic Association: vegetarian diets. J Am Diet Assoc 2009; 109:1266.
- Krajcovicova M, Buckova K, Klimes I, Sebokova E. Iodine deficiency in vegetarians and vegans. Ann Nutr Metab. 2003;47:183185.
- Institute of Medicine, Food and Nutrition Board. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: National Academies Press; 2002.
- Janelle KC, Barr SI. Nutrient intakes and eating behavior scores of vegetarian and nonvegetarian women. J Am Diet Assoc. 1995;95:180-189.
© 2018 Sherry Haynes