
Ali Niklewicz
About
My research project
The utility of genetic risk communication in vitamin B12 deficiency for vegan women of reproductive ageMy PhD project explores the utility of communicating "genetic risk" information within a public health setting, specifically within the context of vitamin B12 deficiency in vegan women of reproductive age. My project investigates precision nutrition in public health, which aims to formulate policy by removing the one-size fits all paradigm. Vegan pregnant women are at a higher risk of vitamin B12 deficiency due to the increased demand for B12 during pregnancy/lactation and the absence of vitamin b12 in unfortified plant-based foods. However, the current policy and UK recommended daily intake of vitamin B12 for pregnant women or women of reproductive age does not consider the increased demand during these times. Further yet, it does not reflect the additional risk of plant-based diets. Therefore, my project aims to investigate whether personalised (genetic risk scores) nutrition information could mitigate the risk of B12 deficiency in vegan women, using risk communication techniques and if it could apply to public health.
Supervisors
My PhD project explores the utility of communicating "genetic risk" information within a public health setting, specifically within the context of vitamin B12 deficiency in vegan women of reproductive age. My project investigates precision nutrition in public health, which aims to formulate policy by removing the one-size fits all paradigm. Vegan pregnant women are at a higher risk of vitamin B12 deficiency due to the increased demand for B12 during pregnancy/lactation and the absence of vitamin b12 in unfortified plant-based foods. However, the current policy and UK recommended daily intake of vitamin B12 for pregnant women or women of reproductive age does not consider the increased demand during these times. Further yet, it does not reflect the additional risk of plant-based diets. Therefore, my project aims to investigate whether personalised (genetic risk scores) nutrition information could mitigate the risk of B12 deficiency in vegan women, using risk communication techniques and if it could apply to public health.
Publications
The dietary intake of vitamin B12 among unsupplemented vegans is notably lower compared to both vegetarians and omnivores. Prolonged low intakes of vitamin B12, such as seen in those adhering to a vegan diet, lead to physiological deficiency of vitamin B12 and an elevated risk of B12-related morbidity. However, while serum B12 serves as a conventional biomarker for assessing B12 status, its utility is limited given its sensitivity and specificity in ascribing physiological deficiency of B12 and the functional vitamin B12 status of those adhering to vegan diets is unclear. We conducted a systematic review and meta-analysis using data based on the full panel of biomarkers of vitamin B12 status to test whether adherence to a vegan diet is associated with an elevated risk of functional vitamin B12 deficiency compared to vegetarian or omnivorous diets. In addition, subgroup analysis was carried out to look at the effect of vitamin B12 supplement use on B12 status among vegans. Our search identified 4002 records, of which 19 studies met the inclusion criteria for the systematic review and 17 studies were taken forward for the meta-analysis. Meta-analysis results revealed significantly lower serum B12, pmol/ (-0.72 [-1.26, -0.18]; p = 0.01) and elevated total homocysteine, mu mol/L (tHcy) (0.57 [0.26, 0.89]; p < 0.001) concentrations, alongside elevated methylmalonic acid, nmol/L (MMA) (0.28 [-0.01, 0.57]; p = 0.06) and lower holotranscobalamin, pmol/ (HoloTC) (-0.42 [-0.91, 0.07]; p = 0.09) levels among vegan adults compared to omnivores, indicating increased functional B12 deficiency in addition to low vitamin B12 status in vegan adults. There were no differences between vegans and vegetarians in HoloTC (0.04 [-0.28, 0.35]; p = 0.814) or MMA (-0.05 [-0.29, 0.20]; p = 0.708), but differences were found in serum B12 (-0.25 [-0.40, -0.10]; p = 0.001) and for tHcy (0.24 [0.09, 0.39]; p = 0.002) concentrations. Subgroup analyses indicated that the use of vitamin B12 supplements among vegans contributes to significant improvements in all biomarker concentrations compared to their unsupplemented counterparts. Our findings underscore the need for improved strategies to redress poor vitamin B12 status with appropriate B12 supplementation use among those adhering to vegetarian and vegan diets.