Assessing the efficacy of Chlorella vulgaris for Vitamin B12 Deficiency: A Randomized Controlled Trial

ContextVitamin B12 deficiency is common among vegans and vegetarians due to limited intake of animal-derived foods. Identifying safe, plant-based sources of vitamin B12 is essential to address this nutritional gap. AimsThis study evaluated the efficacy and safety of Chlorella vulgaris tablets in improving vitamin B12 deficiency. Settings and DesignA double-blind, randomized, placebo-controlled trial was conducted among 46 healthy adults with vitamin B12 deficiency (serum levels 107-210 pmol/L). Methods and MaterialParticipants were randomized (1:1) to receive C. vulgaris (1 g twice daily) or identical placebo for 12 weeks. Primary outcome was change in serum vitamin B12; secondary outcomes included folic acid, homocysteine, methylmalonic acid (MMA), and quality of life (WHO-QoL). Assessments were conducted at baseline and week 12, with safety monitored through liver and kidney function tests and adverse event reporting. Statistical Analysis UsedSample size (n=46) was calculated with 90% power and 10% dropout allowance. Data were analyzed using SPSS v22. Non-parametric tests were applied after normality assessment, with p<0.05 considered significant. ResultsOf 46 participants (mean age 35.5 {+/-} 11.2 years; 69.6% female), mean serum vitamin B12 levels were significantly higher in the C. vulgaris group than in the placebo group at 12 weeks (214.4 {+/-} 160.8 vs 55.9 {+/-} 15.0 ng/mL; P < .001). No significant differences were observed in folic acid, homocysteine, MMA, or QoL scores between groups. No adverse events were reported. ConclusionsSupplementation with Chlorella vulgaris significantly improved serum vitamin B12 levels, suggesting its potential as a safe, plant-based alternative for managing vitamin B12 deficiency. Key MessagesO_LIPlant-based Chlorella vulgaris improved vitamin B12 levels significantly C_LIO_LIRandomized trial in B12-deficient healthy adults over 12 weeks C_LIO_LINo adverse effects observed on liver or kidney function tests C_LIO_LIQuality of life improved across all domains in the intervention group C_LI