All Vegan Things 3 - Vegan Performance II

In part 2 of the series, I delved a little into the macronutrient composition of vegan diets, and highlighted some of the problems they encounter. In part 3 of the series, I intend on discussing some of the micronutrients deficiencies that vegans need to deal with, and then give a quick overview thereabout. Lassen uns beginnen…


Obtaining sufficient micro-nutrients is detrimental for health, let alone sports performance, whereby higher intakes deem necessary for optimal results. As such, structuring the athletic diet correctly, in my opinion, is just as important as the training if not more. Make no mistake, when it comes to sports and performance, food is a tool, not a luxury.

To that end, addressing these deficiencies is of great importance, as it helps prevent complications down the line. Thankfully, these deficiencies are rare in omnivores athletes, but unfortunately plentiful in a vegan diet (B12, zinc, iron, iodine, calcium, vitamin D) [1]. I will try to keep this short of a long article and will briefly review these deficiencies.


Vitamin B12 (Cobalamin) is among the most important vitamins humans need, as its essential for nervous system development and function, homocysteine metabolism and DNA synthesis. A lack therein poses serious health risks, such as megaloblastic anemia, neuropathy (nerve problems), and irreversible neurological damage. That is no joke, but you don’t need me to tell you that.

Approx. 50% of the vegan UK population is B12 deficient [2], and another 21% are classified as very low. Weirdly enough, 20% of the study sample was supplementing B12 orally and was still, deficient, suggesting that oral supplementation may not be enough. By that token, vegans may need to have regular medical check-ups, and consider B12 intramuscular injections in order to stave off the deficiency [3].

Iron & Zinc

Iron deficiency is the commonest of all micronutrient deficiencies seen in the general populous; vegans are at higher risks for being deficient therein. Although, both vegans and omnivores consume similar amounts of iron, the iron in vegan diets is less bioavailable as it lacks the chemical or structural form of better Absorption.

To illustrate further, plants have non-haem iron, whereas iron found in meats is of haem group. This difference has to do with the reductive state of the iron compound and affects how our bodies contend with it; ferric iron (non-haem) is difficult to absorb when compared to ferrous iron (haem) that is readily taken up into our bodies [4].

With this in mind, Lack of iron produces iron-deficiency anemia; its symptoms range from fatigue, weakness, and exercise intolerance to possible death if left untreated. Unfortunately, this is more common in women, and more so in vegan women [5] [6] [7].

Similarly, zinc is plentiful in vegan foods, but of low bioavailability as well. Keep in mind that zinc is required for protein metabolism, DNA repair and cell growth. A lack thereof is quite problematic. Then again, there remains research suggesting that the body adapts to lower zinc intakes and maintains equilibrium, although the studies cited were of extreme short duration [8].

In spite of that, The Institute of Medicine (IOM) recommends significantly higher zinc & iron intakes for vegans; 150% and 180% respectively [9] [10].


EPA & DHA are essential fatty acids; they are so because we cannot synthesize them in our bodies. They are also known as n-3 fatty acids and by large found in marine sources. They have significant health and performance implications, including cardioprotective effects, anti-inflammatory features and performance enhancing capabilities [11] [12] [13]. Consequently, it is highly recommended of athletes to consume sufficient amounts thereof.

I however, will refrain from discussing DHA & EPA as both omnivore and vegan athletes must supplement them to obtain ideal values, although omnivores are free to consume fish on daily basis, whereas vegans cannot consume fish at all, and may opt for micro-algae oils.

Calcium & Vitamin D

Calcium, a distinct vitamin is involved in both daily life function and long-term health, whereby its responsible for muscular contractility (including cardiac tissue), neurotransmitter secretion, blood clotting, digestion, and bone density [14]. Blood level a calcium is tightly regulated, hence, experiencing serious contractility problems is the rarest of events, unless subjected to specific stresses; however, it can present with subclinical symptoms such as those horrid calf cramps when sleeping, if you’ve ever experienced one.

Similarly, prolonged deficiency of calcium predisposes for osteoporosis and increases risk of fracture in old age due to decreased bone mineral density. Mind you, this takes years to develop, but if ignored, can genuinely result in cascade of events with result of death.

With that fluff of information, vegan’s calcium intake seems to be about 40% lower than that of omnivores, as dairy consumption is prohibited [5] [15]. Keep the above-mentioned in mind, vegan do have lower bone mineral density (BMD) than omnivores by about 4-6%, but was concluded to be clinically non-significant [16]. It is something to be wary of where more clinical research is needed.

On the other hand, vitamin D values of vegans seem to be lower than that of omnivores, which can be explained by their sourcing as they tend to hold the inactive form of the vitamin (D2), whereas omnivore sources tend to contain the active form of the vitamin (D3) [17] [18]. This again indicates a possible increase in daily recommendations, and preferably supplementation. That said, obtaining vitamin D is crucial for bone health, a number a physiological processes, and might improve sports performance, particularly when deficient [19] [20] [21].

Wrap up & a snippet on Social Factors

In conclusion, vegans need to contend with a multitude of micro-nutrient deficiencies, as it seems that two or more things need supplementing on daily basis to stave them off. And there is nothing particularly wrong with that, but it is subpar and by no margin ideal from a view of self-sufficient dieting and sustenance.

Beyond that, exists a neglected aspect in the literature, which is the lifestyle aspect of adherence to vegan diets or no man’s land as I’d like to call it. Having to deal with bloating, bathroom breaks, gas, and other gastrointestinal symptoms can be quite irritating, especially for females whether athletic or not.

Moreover, nutrient fortified vegan foods & vegan supplements can be quite expensive to sustain, and I hating using this word, but there is a prerogative that comes with being able to afford these foods on regular basis, especially where I live for the moment. The psychological & social impacts need to be taken into consideration when one wishes to switch to a vegan-based diet.

This concludes part 3 of the series and marks the end thereof. In my next article I will review some of the literature cited from the game changers, and then give the documentary a good bashing. It is going to be short of boring. Talk soon…


1. Anon. “Position of the American Dietetic Association: Vegetarian Diets.” Journal of the American Dietetic Association, vol. 109, no. 7, July 2009, pp. 1266–1282, 10.1016/j.jada.2009.05.027.

2. Ball, M. J., and M. L. Ackland. “Zinc Intake and Status in Australian Vegetarians.” British Journal of Nutrition, vol. 83, no. 1, Jan. 2000, pp. 27–33, 10.1017/s0007114500000052. Accessed 2 Jan. 2020.

3. CANNELL, JOHN J., et al. “Athletic Performance and Vitamin D.” Medicine & Science in Sports & Exercise, vol. 41, no. 5, May 2009, pp. 1102–1110, 10.1249/mss.0b013e3181930c2b. Accessed 30 Oct. 2019.

4. Ceglia, Lisa. “Vitamin D and Skeletal Muscle Tissue and Function.” Molecular Aspects of Medicine, vol. 29, no. 6, Dec. 2008, pp. 407–414, 10.1016/j.mam.2008.07.002. Accessed 8 July 2019.

5. Crowe, Francesca L, et al. “Plasma Concentrations of 25-Hydroxyvitamin D in Meat Eaters, Fish Eaters, Vegetarians and Vegans: Results from the EPIC–Oxford Study.” Public Health Nutrition, vol. 14, no. 02, 21 Sept. 2010, pp. 340–346, 10.1017/s1368980010002454. Accessed 18 Feb. 2019.

6. Davey, Gwyneth K, et al. “EPIC–Oxford:Lifestyle Characteristics and Nutrient Intakes in a Cohort of 33 883 Meat-Eaters and 31 546 Non Meat-Eaters in the UK.” Public Health Nutrition, vol. 6, no. 03, June 2003, 10.1079/phn2002430.

7. Fuhrman, Joel, and Deana M. Ferreri. “Fueling the Vegetarian (Vegan) Athlete.” Current Sports Medicine Reports, vol. 9, no. 4, July 2010, pp. 233–241,, 10.1249/jsr.0b013e3181e93a6f. Accessed 5 Mar. 2019.

8. Gilsing, A M J, et al. “Serum Concentrations of Vitamin B12 and Folate in British Male Omnivores, Vegetarians and Vegans: Results from a Cross-Sectional Analysis of the EPIC-Oxford Cohort Study.” European Journal of Clinical Nutrition, vol. 64, no. 9, 21 July 2010, pp. 933–939, 10.1038/ejcn.2010.142.

9. Harris, William S., et al. “Omega-3 Fatty Acids and Coronary Heart Disease Risk: Clinical and Mechanistic Perspectives.” Atherosclerosis, vol. 197, no. 1, 1 Mar. 2008, pp. 12–24,, 10.1016/j.atherosclerosis.2007.11.008. Accessed 8 May 2020.

10. Ho-Pham, Lan T, et al. “Effect of Vegetarian Diets on Bone Mineral Density: A Bayesian Meta-Analysis.” The American Journal of Clinical Nutrition, vol. 90, no. 4, 1 July 2009, pp. 943–950, 10.3945/ajcn.2009.27521. Accessed 10 May 2019.

11. Hunt, Janet R. “Moving toward a Plant-Based Diet: Are Iron and Zinc at Risk?” Nutrition Reviews, vol. 60, no. 5, 1 May 2002, pp. 127–134, 10.1301/00296640260093788. Accessed 6 Nov. 2019.

12. JANELLE, K.CHRISTINA, and SUSAN I. BARR. “Nutrient Intakes and Eating Behavior See of Vegetarian and Nonvegetarian Women.” Journal of the American Dietetic Association, vol. 95, no. 2, Feb. 1995, pp. 180–189, 10.1016/s0002-8223(95)00045-3. Accessed 8 Dec. 2019.

13. Mickleborough, Timothy D., et al. “Effect of Fish Oil-Derived Omega-3 Polyunsaturated Fatty Acid Supplementation on Exercise-Induced Bronchoconstriction and Immune Function in Athletes.” The Physician and Sportsmedicine, vol. 36, no. 1, Jan. 2008, pp. 11–17, 10.3810/psm.2008.12.7. Accessed 8 May 2020.

14. Moran, Daniel S., et al. “Vitamin d and Physical Performance.” Sports Medicine (Auckland, N.Z.), vol. 43, no. 7, 1 July 2013, pp. 601–611,, 10.1007/s40279-013-0036-y. Accessed 8 May 2020.

15. Pawlak, R., et al. “The Prevalence of Cobalamin Deficiency among Vegetarians Assessed by Serum Vitamin B12: A Review of Literature.” European Journal of Clinical Nutrition, vol. 70, no. 7, 1 July 2016, p. 866,, 10.1038/ejcn.2016.81. Accessed 8 May 2020.

16. Phillips, Stuart M., and Luc J.C. Van Loon. “Dietary Protein for Athletes: From Requirements to Optimum Adaptation.” Journal of Sports Sciences, vol. 29, no. sup1, Jan. 2011, pp. S29–S38, 10.1080/02640414.2011.619204.

17. Simopoulos, Artemis P. “Omega-3 Fatty Acids and Athletics.” Current Sports Medicine Reports, vol. 6, no. 4, 11 July 2007, pp. 230–236, 10.1007/s11932-007-0037-4. Accessed 12 Sept. 2019.

18. Theobald, H. E. “Dietary Calcium and Health.” Nutrition Bulletin, vol. 30, no. 3, Sept. 2005, pp. 237–277, 10.1111/j.1467-3010.2005.00514.x.

19. Trang, H M, et al. “Evidence That Vitamin D3 Increases Serum 25-Hydroxyvitamin D More Efficiently than Does Vitamin D2.” The American Journal of Clinical Nutrition, vol. 68, no. 4, 1 Oct. 1998, pp. 854–858, 10.1093/ajcn/68.4.854. Accessed 19 Oct. 2019.

20. Waldmann, Annika, et al. “Dietary Iron Intake and Iron Status of German Female Vegans: Results of the German Vegan Study.” Annals of Nutrition and Metabolism, vol. 48, no. 2, 2004, pp. 103–108, 10.1159/000077045. Accessed 20 Apr. 2019.

21. Camaschella, Clara. “Iron-Deficiency Anemia.” New England Journal of Medicine, vol. 372, no. 19, 7 May 2015, pp. 1832–1843, 10.1056/nejmra1401038. Accessed 20 Sept. 2019.


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