Evidence Level
B-Complex supplementation has been extensively studied for its benefits in stress reduction, mood improvement, and cognitive function. A systematic review and meta-analysis by Long and Benton (2013) of eight randomized controlled trials (RCTs) demonstrated significant improvements in perceived stress and mood outcomes, particularly among individuals experiencing occupational stress. The VITACOG trial conducted by Smith et al. (2010) highlighted that high-dose B6/B12/folate supplementation slowed brain atrophy by 30% in elderly subjects with mild cognitive impairment and elevated homocysteine levels. Additionally, Kennedy et al. (2010) found that 90 days of high-dose B-complex supplementation improved cognitive performance and reduced mental fatigue in healthy adults.
Recent studies further support the efficacy of B-Complex. Sarris et al. (2021) reviewed seven RCTs and concluded that high-dose B-complex supplements enhance mental health, stamina, and cognitive function across both healthy and at-risk populations. Furthermore, Nunes et al. (2022) noted that Roux-en-Y gastric bypass surgery leads to higher rates of vitamin B12 deficiency compared to sleeve gastrectomy, underscoring the importance of supplementation in surgical patients. The synergistic interaction among B vitamins suggests that supplementation as a complex is more effective than individual vitamins for most applications.