Vegetarians can be classified into different groups based on how restrictive their diets are when it comes to animal foods. The more restrictive they are the more they have to be cautious about not becoming deficient in certain nutrients such as protein, calcium, vitamin B ₁₂ etc.

History of vegetarianism

Early food cultures were plant-based. Religions like Hinduism and Buddhism have advocated a vegetarian way of life (1). The Greek philosopher Pythagoras is thought to be the father of ethical vegetarianism.

The first vegetarian society was founded in England in 1847.

The International Vegetarian Society began in 1908.

The first vegan society began in 1944.

The reasons for increasing people following vegetarianism

• Ethical
• Health concerns
• Social
• Ecological

The scientific evidence in recent times has been building up which suggests wholesome vegetarian diets present considerable advantages when compared to diets containing foods of animal origin (2).

Benefits of a vegetarian diet include

• Reduced cholesterol, saturated fat and animal protein intake
• Increased intakes of dietary fiber, antioxidants, micronutrients and other phytochemicals.

Vegans

Vegans restrict their diet to plant foods. For example, cereal grains, fruits, vegetables and legumes. Vegans have numerous choices for complementing protein sources. They may have to take supplements to meet recommended dietary allowances of certain nutrients such as B ₁₂.

Different types of vegetarians

Lacto-vegetarians

These people include milk and dairy products to a vegan diet. Milk is a complete source of protein. Also, dairy products are good sources of calcium. Soy products and dairy products make meeting nutrient recommendations a little easier for this group.

Ovo-vegetarians

This group of people include eggs in their diet. Eggs are a complete source of protein and several recipes can be made from eggs. Soy products and eggs together make it easier for them to meet nutrient recommendations.

Lacto-ovo-vegetarians

This group can include dairy products and eggs in their diet. Soy also can be included in the diet. It is quite easy to meet all the nutritional requirements for this group of people (3).

Concerns regarding vegetarianism

Earlier it was thought that vegetarianism would lead to malnutrition. But scientific evidence shows that vegetarians can be nourished well if they plan their diets and also vegetarianism can reduce the risk of certain diseases (1). Internationally the number of people following vegetarianism is picking up and this is because of various reasons.

Vegan and vegetarian diets have their own advantages as far as health is concerned

• Because of lower levels of cholesterol and saturated fat, it reduces the risk of cardiovascular diseases.
• Substituting animal protein with plant protein improves lipid profile. Therefore, effective in reducing the risk of heart related problems. Similar positive results were seen when animal protein is replaced by plant protein on glucose levels in the blood (4, 5).
• Higher content of dietary fiber in vegetarian diets helps in managing blood glucose and cholesterol levels which is also beneficial in reducing the risk of diabetes and cardiovascular diseases (6).

Final word

In general, it is thought that vegan and vegetarian diets lack nutrients such as vitamin B₁₂, proteins, zinc, calcium etc. If care is taken to plan the diet properly and including supplements where necessary, the deficiencies can be prevented. It helps a person to have reduced risk of developing cardiovascular diseases and diabetes.

References

1. Leitzman, C. (2014) Vegetarian Nutrition: Past, present, future, The American Journal of Clinical Nutrition. Vol.100 (1).
   https://www.ncbi.nlm.nih.gov/pubmed/24898226

2. Mehta, V. (2018) Vegetarian Diet: A Boon or Bane for Health?, Journal of Medical Research Innovation. 2(1).
   https://jmrionline.com/index.php/jmri/article/view/84

3. Wildman, R. (2009) The Nutritionist-Food, Nutrition, and Optimal Health, Second Edition; How our body works 18; Routledge, Taylor and Francis Group, New York and London.
4. Dahl and Stewart (2015) Position of the Academy of Nutrition and Dietetics: Health Implications of Dietary Fiber, J Acad Nutr Diet.  115( 11).
   https://www.ncbi.nlm.nih.gov/pubmed/26514720

5. Li, S.S., Mejia, B.S., Lytvyn, L ., Stewart, S.E., Viguiliouk, E., Ha, V., de Souza, R.J., Leiter, L.A., Kendall, C.W.C., Jenkins, D.J.A. and Sievenpiper, J.L.(2017) Effect of Plant Protein on Blood Lipids: A Systematic Review and Meta-Analysis of Randomized Controlled Trials, J Am Heart Assoc. Vol. 12(6).
   https://www.ncbi.nlm.nih.gov/pubmed/29263032

6. Viguiliouk, E., Stewart,S.E., Jayalath, V.H., Ng, A.P., Mirrahimi, A., de Souza, R.J., Hanley, A.J., Bazinet, R.P.,  Mejia, B. S., Leiter, L.A., Josse, R.G., Jenkins, D.J. and Sievenpiper, J.L.(2015) Effect of Replacing Animal Protein with Plant Protein on Glycemic Control in Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trial, Nutrients. Vol.7 (12).
   https://www.ncbi.nlm.nih.gov/pubmed/26633472