Humans have survived in unique and diverse environments, to include equally unique and diverse foods and dietary habits. However, it is also true that particular nutritional proclivities have the potential to induce unfavorable physiological consequences that inhibit optimal health and longevity. In the following sections, I would like to explore vegan/vegetarian diets, strengths, limitations, and their relationships to micronutrient deficiencies, with particular emphasis upon thiamine.
In Switzerland, Schupbach, Wegmuller, Berguerand, and Herter-Aeeberli (2017) indicated that vegetarian (VG) and vegan (VN) diets have gained popularity in recent years; meat consumption has decreased from 32.7 % in 1992 to 23.9 % in 2012. The researchers were interested in evaluating the efficacy of such diets compared to traditional omnivore (OV) diets found throughout the region. In particular, Schupbach et al. (2017) examined plasma concentrations of zinc, magnesium, iron, beta carotene, biotin (B7), niacin (B3), pantothenic acid (B5), folic acid (B9), methylcobalamin (B12), pyridoxine (B6), riboflavin (B2), E, C, A, and thiamine (B1). The following sections will consider the results, with a particular focus upon thiamine, and implications from Schupbach et al. (2017).
Schupbach et al. (2017) recruited 206 healthy male and female subjects (18-50 years) who followed either a VG, VN, or OV for at least one year prior to the study. Of the 206 subjects, 53 were VG, while 53 were VN with the remaining 100 were OV (Schupbach et al., 2017). Any supplementation in either group was terminated 14 days prior to the study. Prior to urine and blood collection, each subject fasted overnight to rule out the influence of food upon samples ascertained. Furthermore, each subject provided a 3-day weighted food record during the week after collection of said blood and urine samples (Schupbach et al., 2017). The following will explore the results and implications from the VG/VN/OV dietary approaches.
Although VG and VN diets are gaining momentum in Western civilization, a complete understanding of such diets upon micronutrient status have remained unclear prior to the above study. Of particular interest to this author is thiamine (B1), which has many roles to include energy production, nutrient metabolism, and nervous system function (Gropper, Smith, & Carr, 2018). As such, deficiencies in said vitamin can cause conditions such as beriberi (compromised nervous system and cardiovascular function, among other symptoms). Interestingly, results from Schupbach et al. (2017) indicated that B1 deficiency was not found in the VN, VG, or OV subjects. However, other deficiencies were found among the VN and VG subjects, but are beyond the scope of this author’s review of such diets.
It is likely that thiamine deficiency is not a micronutrient of concern amongst VG/VN groups since B1 is found in several non-animal sources. Such sources can include nuts, beans, lentils, seeds, pasta, rice, bagels, and breads (Gropper et al., 2018). Moreover, results indicated that B1 was highest among the VN group Schupbach et al. (2017). However, non-animal sources are significantly lower, demanding larger intakes of such foods to reach adequate levels of B1.
In conclusion, VG and VN dietary approaches do not appear to induce B1 micronutrient deficiencies. However, it should be noted that, although it is beyond the focus of this author’s review, other micronutrient deficiencies do appear to exist amongst VN/VG subjects (especially VN groups) such as zinc, B12, iron, omega-3 polyunsaturated fats, and vitamin D (Winston, 2009). As such, it is imperative to be aware of the strengths, and weaknesses, of any dietary approach.
References
Gropper, S. S., Smith, J. L., & Carr, T. P. (2018). Advanced nutrition and human metabolism (7thed.). Boston, MA: Cengage Learning.
Schupbach, R., Wegmuller, R., Berguerand, C., Bui, M., & Herter-Aeeberli, I. (2017). Micronutrient status and intake in omnivores, vegetarians, and vegans in Switzerland. European Journal of Nutrition, 56(1), 283-293.
Winston, C. (2009). Health effects of vegan diets. The American Journal of Clinical Nutrition, 89(5), 1627S-1633S.
-Michael McIsaac