Published in 2018, this human, clinical “investigator-blinded” trial examined 264 subjects who were suffering from high levels of stress and low serum magnesium levels but were otherwise healthy adults. The interventions were a magnesium–vitamin B6 (daily dose 300 mg and 30 mg respectively) or magnesium alone (daily dose 300 mg) for 8 weeks. Overall, both treatment arms substantially reduced DASS-42 stress subscale scores from baseline to week 8 though they did not differ significantly. However, analysis of participants who had severe/extremely severe stress (DASS-42 stress subscale score >25; N = 162) at baseline did exhibit a more substantial difference in improvement between groups (24% greater improvement with Mg–vitamin B6 versus Mg alone).
Pouteau E, Kabir-Ahmadi M, Noah L, et al. Superiority of magnesium and vitamin B6 over magnesium alone on severe stress in healthy adults with low magnesemia: A randomized, single-blind clinical trial. PLoS One. 2018;13(12):e0208454. Published 2018 Dec 18. doi:10.1371/journal.pone.0208454