Can athletes excel on a vegetarian diet?

by | Exercise and Fitness

People follow vegetarian diets for a variety of reasons such as religious beliefs, personal and moral values, environmental concerns, health benefits, financial reasons, and a limited food supply.

There is much to recommend a dietary pattern that contains lots of plant-based foods. Yet despite the growing popularity of ‘going vego’, there has been little research done on how such a diet can impact on athletic performance.

In a new study, researchers recruited 27 vegetarian and 43 omnivore competitive endurance athletes. Each person in the vegetarian group had followed the diet for at least two years and there was a mixture of vegan and lacto-ovo vegetarians amongst the group. Food intake, maximal oxygen uptake (VO2max) during treadmill running and leg strength were all assessed.

For the males, there was little difference in cardio-respiratory fitness or strength between the vegetarians and omnivores. The surprising finding though was in the women. Vegetarian women had a 13 percent greater VO2max scores than women eating an omnivore diet.

There was no difference in protein intake according to body weight between vegetarians and omnivores. Although vegetarians ate more carbohydrates and fibre, they had less vitamin B12.

One interesting finding was that vegetarians had more iron in their diet than omnivores. But because plant-based iron is less bioavailable than animal-based iron, then this may bring the vegetarians back on par with omnivores.


A well-planned and varied vegetarian diet can meet the nutritional needs of an athlete just as well as an omnivore diet. Such a diet poses little risk of sub-par performance and, for some athletes, it may even spur them on to higher levels of achievement.