By Marco Pagliarulo, Weird Veg Science columnist for Lifelines

untitled1Vegan athletes assert that a plant-based diet gives them a leg up. Let’s explore the science behind this claim.

Endurance exercise induces muscle damage and inflammation throughout the body [1].  Since this can impede tissue repair and the body’s recovery [2], minimizing inflammation is advantageous to the athlete.

But what does this have to do with diet? Several human studies have investigated the relationships between dietary patterns and inflammation. Here’s what the body of  knowledge indicates:

  • Meat-based diets and Western dietary patterns (characterized by high intakes of meat, sweets, and refined grains) are associated with chronic inflammation [3, 4].
  • Conversely, fruit- and vegetable -based diets are associated with decreased levels of  inflammation [3, 4].
  • High intakes of carotenoids and vitamin C (found mostly in plant-based foods) seem  to decrease inflammation [3].
  • The consumption of whole grains is also associated with decreased levels of  inflammation [3, 5].

One of the review papers even goes on to suggest that a diet high in vegetables, fruit, and whole grains may even protect the body against inflammation [3]. Aside from inducing inflammation, exercise may also induce oxidative stress [6] – an imbalance in the body between free radicals (which cause damage to our cells) and antioxidants. Although the relationship between diet and oxidative stress is not always clear, several studies report that athletes consuming diets high in antioxidants may reduce oxidative stress in their tissues; accordingly, athletes have been encouraged to consume diets rich in natural antioxidants such as fruits, vegetables, whole grains, legumes, sprouts, and seeds [7, 8, 9].

It seems that athletes consuming more  antioxidants in their diet have higher levels of antioxidants in their blood [10]. The benefits of plant-based food to athletes shouldn’t be a surprise though. Archaeological evidence shows that the greatest athletes of Ancient Rome – both the  gladiators and the Roman army troopers – were on a mostly plant-based diet [11].

The overall weight of evidence shows that a whole-food plant-based diet decreases  inflammation and that meat-based and Western diets increase inflammation. A plant-based diet is also recommended for athletes to help counteract oxidative stress. So, what does this all mean? Well, if you engage in strenuous exercise, consider a whole-food. plant-based diet for a faster recovery time and less oxidative tissue damage.


References

[1] Neubauer O, König D, Wagner K-H. 2008. Recovery after an Ironman triathlon: Sustained inflammatory responses and muscular stress. Eur J Appl Physiol 104:417-426.

[2] Tidball JG. 2005. Inflammatory processes in muscle injury and repair. Am J Physiol Regul Integr Comp Physiol 288:R345-R353.

[3] Nanri A, Moore MA, Kono S. 2007. Impact of C-reactive protein on disease risk and its relation to dietary factors: Literature review. Asian Pac J Cancer Prev 8:167-177.

[4] Barbaresko J, Koch M, Schulze MB, Nöthlings U. 2013. Dietary pattern analysis and biomarkers of low-grade inflammation: A systematic literature review. Nutr Rev 71:511-527.

[5] Lefevre M, Jonnalagadda S. 2012. Effect of whole grains on markers of subclinical inflammation. NutrRev 70:387-396.

[6] Pyne DB. 1994. Exercise-induced muscle damage and inflammation: A review. Austral J Sci Med Sport 26:49-58.

[7] Clarkson PM, Thompson HS. 2000. Antioxidants: What role do they play in physical activity and health? Am J Clin Nutr 72(suppl):637S–46S.

[8] Urso ML, Clarkson PM. 2003. Oxidative stress, exercise, and antioxidant supplementation. Toxicol 189:41-54.

[9] Yavari A, Javadi M, Mirmiran P, Bahadoran Z. 2015. Exercise-induced oxidative stress and dietary antioxidants. Asian J Sports Med 6:e24898.

[10] Watson TA, MacDonald-Wicks LK, Garg ML. 2005. Oxidative stress and antioxidants in athletes undertaking regular exercise training. Int J Sport Nutr Exer Metab 15:131-146.

[11] Longo UG, Spiezia F, Maffulli N, Denaro V. 2008. The best athletes in Ancient Rome were vegetarian. J Sports Sci Med 7:565.