Editing Vitamin B6 (section)

==Research==
Observational studies suggested an [[inverse correlation]] between a higher intake of vitamin B<sub>6</sub> and all [[cancer]]s, with the strongest evidence for gastrointestinal cancers. However, evidence from a review of [[randomized controlled trial|randomized clinical trials]] did not support a protective effect. The authors noted that high B<sub>6</sub> intake may be an indicator of higher consumption of other dietary protective micronutrients.<ref>{{cite journal |vauthors=Mocellin S, Briarava M, Pilati P |title=Vitamin B6 and Cancer Risk: A Field Synopsis and Meta-Analysis |journal=J Natl Cancer Inst |volume=109 |issue=3 |pages=djw230 |date=March 2017 |pmid=28376200 |doi=10.1093/jnci/djw230 |url=|doi-access=free }}</ref> A review and two observational trials reporting lung cancer risk reported that serum vitamin B<sub>6</sub> was lower in people with lung cancer compared to people without lung cancer, but did not incorporate any intervention or prevention trials.<ref name=":1">{{cite journal |vauthors=Yang J, Li H, Deng H, Wang Z |title=Association of One-Carbon Metabolism-Related Vitamins (Folate, B6, B12), Homocysteine and Methionine With the Risk of Lung Cancer: Systematic Review and Meta-Analysis |journal=Front Oncol |volume=8 |issue= |pages=493 |date=2018 |pmid=30430082 |pmc=6220054 |doi=10.3389/fonc.2018.00493 |url=|doi-access=free }}</ref><ref>{{cite journal |last1=Fanidi |first1=A |last2=Muller |first2=DC |last3=Yuan |first3=J |last4=Stevens |first4=VL |last5=Weinstein |first5=SJ |date=January 2018 |title=Circulating Folate, Vitamin B6, and Methionine in Relation to Lung Cancer Risk in the Lung Cancer Cohort Consortium (LC3) |journal=Journal of the National Cancer Institute |volume=110 |issue=1 |pages=57–67 |doi=10.1093/jnci/djx119 |issn=1460-2105 |pmc=5989622 |pmid=28922778}}</ref><ref>{{cite journal |last1=Johansson |first1=M |last2=Relton |first2=C |last3=Ueland |first3=PM |last4=Vollset |first4=SE |last5=Midttun |first5=Ø |date=June 2010 |title=Serum B Vitamin Levels and Risk of Lung Cancer |journal=JAMA |volume=303 |issue=23 |pages=2377–85 |doi=10.1001/jama.2010.808 |pmid=20551408 |issn=0098-7484 |doi-access=free |url=https://researchonline.lshtm.ac.uk/id/eprint/2587/1/Serum%20B%20Vitamin%20Levels%20and%20Risk%20of%20Lung%20Cancer.pdf |access-date=March 20, 2024 |archive-date=November 21, 2023 |archive-url=https://web.archive.org/web/20231121064850/https://researchonline.lshtm.ac.uk/id/eprint/2587/1/Serum%20B%20Vitamin%20Levels%20and%20Risk%20of%20Lung%20Cancer.pdf |url-status=live }}</ref>

According to a prospective [[cohort study]] the long-term use of vitamin B<sub>6</sub> from individual supplement sources at greater than 20&nbsp;mg per day, which is more than ten times the adult male RDA of 1.7&nbsp;mg/day, was associated with an increased risk for lung cancer among men. Smoking further elevated this risk.<ref>{{cite journal|vauthors=Brasky TM, White E, Chen CL |date=October 2017|title=Long-Term, Supplemental, One-Carbon Metabolism-Related Vitamin B Use in Relation to Lung Cancer Risk in the Vitamins and Lifestyle (VITAL) Cohort|journal=Journal of Clinical Oncology |volume=35|issue=30|pages=3440–3448|doi=10.1200/JCO.2017.72.7735|issn=1527-7755|pmc=5648175|pmid=28829668}}</ref> However, a more recent review of this study suggested that a causal relationship between supplemental vitamin B<sub>6</sub> and an increased lung cancer risk cannot be confirmed yet.<ref>{{cite journal |last1=Calderon-Ospina |first1=CA |last2=Nava-Mesa |first2=MO |last3=Paez-Hurtado |first3=AM |date=2020 |title=Update on Safety Profiles of Vitamins B1, B6, and B12: A Narrative Review |journal=Therapeutics and Clinical Risk Management |volume=16 |pages=1275–88 |doi=10.2147/TCRM.S274122 |issn=1176-6336 |pmc=7764703 |pmid=33376337 |doi-access=free }}</ref>

For [[coronary heart disease]], a [[meta-analysis]] reported lower relative risk for a 0.5&nbsp;mg/day increment in dietary vitamin B<sub>6</sub> intake.<ref>{{cite journal |vauthors=Jayedi A, Zargar MS |title=Intake of vitamin B6, folate, and vitamin B12 and risk of coronary heart disease: a systematic review and dose-response meta-analysis of prospective cohort studies |journal=Crit Rev Food Sci Nutr |volume=59 |issue=16 |pages=2697–707 |date=2019 |pmid=30431328 |doi=10.1080/10408398.2018.1511967 |s2cid=53430399 |url=}}</ref> As of 2021, there were no published reviews of randomized clinical trials for coronary heart disease or cardiovascular disease. In reviews of observational and intervention trials, neither higher vitamin B<sub>6</sub> concentrations<ref>{{cite journal |vauthors=Zhang C, Luo J, Yuan C, Ding D |title=Vitamin B12, B6, or Folate and Cognitive Function in Community-Dwelling Older Adults: A Systematic Review and Meta-Analysis |journal=J Alzheimers Dis |volume=77 |issue=2 |pages=781–94 |date=2020 |pmid=32773392 |doi=10.3233/JAD-200534 |s2cid=221100310 |url=}}</ref> nor treatment<ref>{{cite journal |vauthors=Ford AH, Almeida OP |title=Effect of Vitamin B Supplementation on Cognitive Function in the Elderly: A Systematic Review and Meta-Analysis |journal=Drugs Aging |volume=36 |issue=5 |pages=419–34 |date=May 2019 |pmid=30949983 |doi=10.1007/s40266-019-00649-w |s2cid=96435344 |url=}}</ref> showed any significant benefit on [[cognition]] and [[dementia]] risk. Low dietary vitamin B<sub>6</sub> correlated with a higher risk of [[depression (mood)|depression]] in women but not in men.<ref>{{cite journal |vauthors=Wu Y, Zhang L, Li S, Zhang D |title=Associations of dietary vitamin B1, vitamin B2, vitamin B6, and vitamin B12 with the risk of depression: a systematic review and meta-analysis |journal=Nutr Rev |volume= 80|issue= 3|pages= 351–366|date=April 2021 |pmid=33912967 |doi=10.1093/nutrit/nuab014 |url=}}</ref> When treatment trials were reviewed, no meaningful treatment effect for depression was reported, but a subset of trials in [[pre-menopausal]] women suggested a benefit, with a recommendation that more research was needed.<ref>{{cite journal |vauthors=Williams AL, Cotter A, Sabina A, Girard C, Goodman J, Katz DL |title=The role for vitamin B-6 as treatment for depression: a systematic review |journal=Fam Pract |volume=22 |issue=5 |pages=532–7 |date=October 2005 |pmid=15964874 |doi=10.1093/fampra/cmi040 |url=|doi-access= }}</ref> The results of several trials with children diagnosed as having [[autism spectrum disorder]] (ASD) treated with high dose vitamin B<sub>6</sub> and [[magnesium]] did not result in treatment effect on the severity of symptoms of ASD.<ref>{{cite journal |vauthors=Li YJ, Li YM, Xiang DX |title=Supplement intervention associated with nutritional deficiencies in autism spectrum disorders: a systematic review |journal=Eur J Nutr |volume=57 |issue=7 |pages=2571–82 |date=October 2018 |pmid=28884333 |doi=10.1007/s00394-017-1528-6 |s2cid=3999214 |url=}}</ref>