Determination of Vitamin B12 Deficiency Status in Vegan and Non-Vegan Thais by Assessment of Homocysteine Level

Abstract

OBJECTIVES: To determine and compare vitamin B12 status in different food patterns by using serum homocysteine levels in two adult groups consisting of (1) one hundred participants in non-vegan group and (2) two hundred participants in vegan group. The vegan group is further divided into two subgroups (2.1) ordinary vegan who consumes vegan diets for more than three years and less than twenty years (2.2) high risk vegan who consumes vegan diets for more than twenty years or those who are over 65 years old or those who have signs or symptoms suggesting vitamin B12 deficiency. MATERIAL AND METHODS: This study is a descriptive cross-sectional study designed to compare the status of vitamin B12 using homocysteine level in the total 300 participants in vegan and non-vegan Thais, performed in October 2018. The study used a chemiluminescent microparticle immunoassay (CMIA) using an Architec machine to determine blood homocysteine levels. Their levels of homocysteine were then compared. The data was analyzed using the unpaired t -test. RESULT: Three hundred non-vegan and vegan Thais were included in this study. One hundred and five of these were male and 195 were female. Of these, 41% had high homocysteine levels (more than 15.4 Umol/L.), 59% of them had normal homocysteine levels (less than 15.4 Umol/L). Among one hundred non-vegans Thais (gr.1), there was only one (1%) who had a high homocysteine level. Among one hundred ordinary vegans (gr.2.1), fifty-two (52%) of them had abnormally high homocysteine. Among one hundred of high-risk vegans (gr.2.2), seventy of them (70%) had high homocysteine level. The vegan group had higher blood levels of homocysteine ( p < 0.001) than the non-vegan group. CONCLUSION: Vegan Thais have higher risk of vitamin B12 deficiency as determined by their abnormally higher homocysteine blood levels than that of non-vegans ( p < 0.001). We recommend that all Thai vegans should take vitamin B12 supplements regularly to prevent vitamin B12 deficiency. The dosage recommended by the American Vegetarian Medical Association is 50-100 micrograms per day or 500-1,000 micrograms per week. Thai vegans who do not take B12 supplementation should be screened for B12 deficiency.