What Are The Dangers Of The Modern Vegetarian Diet?

Vegetarianism is making a splash across the globe, with celebrities extolling its virtues, fitness and health experts endorsing it wholeheartedly, and niche restaurants rhapsodizing over the possible combinations. But for all the brownie points it is getting, is there a possibility that vegetarianism can do harm to your body?

A vegetarian diet is one devoid of animal-based foods in any form. Over the years, vegetarianism has evolved into many sub-groups.

  • Lacto-ovo vegetarians don’t eat meat, but do include milk and its products in their diets.
  • Lacto-vegetarians include milk and its products, but do not include eggs.
  • Vegans eat only plant-based food and no derivatives at all from animals, including eggs, milk, honey, and the like.
  • Pescatarians include plant derivatives and seafood in their diets.

The reasons for vegetarianism vary globally. While some follow it for religious purposes, others look at it as a non-violent way of life. Some others believe in the higher health benefits, and for a few others it is just a matter of taste.

Vegetarianism: The Way To Go?

The American Dietetic Association endorses a well-planned vegetarian or vegan diet and its role in preventing as well as treating some ailments.1 A vegetarian diet may reduce the risk of obesity and heart disease, high blood pressure, and Type 2 diabetes.2 Also, if you are a vegetarian, your intake of calories from saturated fat is lower while that of essential nutrients like fiber, potassium, and Vitamin C is higher.


The general consensus, backed by many studies, is that when done right, vegetarianism does mean a healthier lifestyle.3 The operative words, however, is “done right!”

The Flip Side Of Vegetarianism

Research on vegetarianism extends into two directions. While some studies examine the consequences of long-term vegetarianism on the human constitution, other studies evaluate the nutritional deficiencies that can result from an imbalanced vegetarian diet.


Although studies predominantly show that there is a lower incidence of cancer among vegetarians than among non-vegetarians, some recent research veers in the other direction. One study shows that vegetarians may be as prone to colorectal cancer as their meat-eating peers.4 A Cornell University study has found evidence of a mutation that could spell trouble: vegetarians who did not consume a balanced omega-6 to omega-3 diet were found to be prone to inflammation, colon cancer, and even increased risks of heart disease. This may be because of a genetic mutation in successive generations of vegetarians that makes it easier for them to absorb essential fatty acids from plants. While this is good, it also results in a vegetarian being unable to make long chain polyunsaturated fats and particularly arachidonic acid, leading to possibilities of inflammatory disease, heart trouble, and cancer.5

Vegetarian Diet Can Cause Lower Sperm Count

Studies also show that a primarily vegan or vegetarian diet can cause a lower sperm count in men. Vegetarianism affects the parameters of healthy sperm, particularly the estrogenic levels and this can cause low motility.6


Genetic And Physiological Impact Of Vegetarianism

Research on the genetic and physiological impact of vegetarianism continues. But there is no dispute that vegetarianism takes a wrong turn when it’s not properly planned and managed. A consciously healthy blend of nutrients makes for a good vegetarian diet. But often, rather than a healthy, wholesome way of life, vegetarianism turns into a restricted diet, lacking in a balance of carbs, proteins, and fat and leading to several health complications. Though the impact varies from person to person depending on their genetic and individual constitution, there is no question that it does open up health risks, especially related to nutritional deficiencies.

Vegetarianism And Low Bone Density

Repercussions of vegetarianism on bone mineral density have been a focus of ongoing research. A study by Ho-Pham et al. in the American Journal of Clinical Nutrition shows that a long-term vegetarian diet may result in lower bone density.7 The effect was found to be most pronounced in lacto-vegetarians. Although not yet of a magnitude that causes concern, bone mineral deficiency in vegetarians is a red flag. Factors that may come into play are an individual’s personal health profile, genetics, and even where they are located.


According to an Academy of Nutrition and Dietetics report, when compared to meat-eaters, vegetarians tend to have lower levels of iron as iron is not absorbed as effectively from plant foods. This is more prominent in vegetarian women than men, and may lead to anemia. The Food and Nutrition Board recommends an iron recommended daily intake (RDA) for vegetarians that is 1.8 times higher than that for non-vegetarians.8

Vitamin B-12 deficiencies are also common in vegetarians. Unlike some of the other B vitamins, B12 is limited in plant food, while they are found abundantly in many fish and meats and even to some extent in eggs and milk. Vitamin B12 deficiency can cause constipation, fatigue, numbness, memory loss, and even nerve damage in extreme cases. Fortified cereals or soy milk are some options available to vegetarians.


It also makes sense to be clear about your motivation for vegetarianism. Many social studies are examining the use of vegetarianism as a cover for fad dieting and unhealthy food restriction. Equating vegetarianism to detox and weight loss is a dangerous route. In a study by Bardone-Cone et al, a number of study participants revealed that “their vegetarianism was related to their eating disorder (68%) and emerged after its onset.”9 The study encouraged clinicians to review the motives of vegetarianism in such cases.

Balanced Diet

Whatever your motivation for vegetarianism, it’s finally all about what you eat. A general rule of thumb is to ensure that your food sources give you all the nutrients needed. This can be narrowed down on the basis of age, sex, and other nutritional factors. Working with a nutritionist to set the base would be the ideal first step.