Vitamin B6 (pyridoxine hydrochloride) is a widely consumed vitamin, is a naturally occurring vitamin and is safe to consume, and studies have observed the effects of vitamin B6 on these disease biomarkers as well as the effect on cognitive performance.
Take Home Points
Vitamin B6 is associated with significant improvements in long term memory in older adults, as well as in short term memory in younger adults.
Vitamin B6 is associated with lower levels of homocysteine and methylmalonic acid, which are biomarkers associated with cognitive decline.
Vitamin B6, also known as pyridoxine, pyridoxamine, pyridoxal, pyridoxal phosphate, pyridoxal-5'-phosphate, PLP
- the three major forms of Vitamin B6 are pyridoxine, pyridoxal, and pyridoxamine.
Figure 1. Chemical structure of vitamin B6.
Vitamin B6 is found in meats and poultry (e.g. chicken, fish, tuna, salmon, milk, cheese), vegetables (e.g. spinach, carrots, beans), and grains (e.g. bran, wheat, brown rice).
Effects on Cognition
After conversion to its active form, vitamin B6 can carry certain physiological effects: increase dopamine levels, reduce fatty acid synthase activity, increase prolactin, potentially increase growth hormones.
Vitamin B6 for 12 weeks yielded a significant improvement in performance on a long term memory storage test in elderly men.1
Vitamin B6 supplementation was associated with increased performance on short term memory tasks, namely the word recall task, in a double-blind,randomized, placebo-controlled trial, with greater effects in the younger adults compared to older adults.2
Vitamin B6 (25mg) was associated with improved performance in the Telephone Interview for Cognitive Status (TICSm) test as well as the Letter Digit Coding Test, as shown in 185 elderly men with vascular disease.3
Vitamin B6 supplementation resulted in lower levels of homocysteine, but this did not correlate with increased memory, as measured by Wechsler Paragraph Recall test, and executive function as measured by Part B of the Reitan Trail Making Test.4
Vitamin B6 led to lower levels of serum homocysteine and methylmalonic acid, and there were also increases in memory including identifical forms test, synonym test, digit symbol test, Thurstone's picture memory test and figure classification test in another study with 209 subjects.5
Vitamin B6 correlated with approximately 30% lower levels of homocysteine, which is a biomarker linked with dementia.6
Vitamin B6 over a 3-year period was associated with improvement in executive function, as measured by the Figure Copying Task component of the Mini Mental Status Examination, in a study of 321 aging men (see figure 1). Higher dosages generally correlated with greater improvements, with the most effective dosage being 3.1mg/day.7
Figure 1. Supplementation with vitamin B6 over a prolonged span was correlated with improvements in the figure copying score, a measure of executive function, in elderly adults.
Effects on Disease States
Most of the medical research surrounding vitamin B6 centers around its effect on lowering disease biomarkers, such as homocysteine and methylmalonic acid.
High levels of homocysteine in the body have been correlated with increased risk of vascular disease.
A study in 185 elderly patients with vascular disease showed that ingestion of vitamin B6 did not result in decreased homocysteine levels, but B12 ingestion did lead to decreased homocysteine.
Figure 2. Supplementation with vitamin B6 and B12 is associated with decreases in levels of inflammatory biomarkers for vascular dementia such as homocysteine, thromboxane and isoprostane.
How to take
Take a dosage of around 1.3-2 mg of vitamin B6 per day. We recommend closer to 2 mg/day for people over the age of 50, and for pregnant and breastfeeding mothers.
Consider taking vitamin B6 supplements if you are at risk for deficiency or may require more than the average diet allows. For example, if you are on a vegan diet that has difficulty getting B vitamins, or if you are an older individual over the age of 50.
Rare in healthy people, minor side effects include: nausea, vomiting, stomach pain, headache, tingling, drowsiness.
Approved as a dietary supplement component under provisions of the Dietary Supplement Health and Education Act of 1994.
Avoid doses of over 100 mg per day. Excessive dosages greater than 300 mg per day can potentially lead to nerve damage, but it is rare.
Deijen, J. B., Van der Beek, E. J., Orlebeke, J. F., & Van den Berg, H. (1992). Vitamin B-6 supplementation in elderly men: effects on mood, memory, performance and mental effort. Psychopharmacology, 109(4), 489-496.
Bryan, J., Calvaresi, E., & Hughes, D. (2002). Short-term folate, vitamin B-12 or vitamin B-6 supplementation slightly affects memory performance but not mood in women of various ages. The Journal of nutrition, 132(6), 1345-1356.
Stott, D. J., MacIntosh, G., Lowe, G. D., Rumley, A., McMahon, A. D., Langhorne, P., ... & MacFarlane, P. W. (2005). Randomized controlled trial of homocysteine-lowering vitamin treatment in elderly patients with vascular disease. The American journal of clinical nutrition, 82(6), 1320-1326.
McMahon, J. A., Green, T. J., Skeaff, C. M., Knight, R. G., Mann, J. I., & Williams, S. M. (2006). A controlled trial of homocysteine lowering and cognitive performance. New England Journal of Medicine, 354(26), 2764-2772.
Lewerin, C., Matousek, M., Steen, G., Johansson, B., Steen, B., & Nilsson-Ehle, H. (2005). Significant correlations of plasma homocysteine and serum methylmalonic acid with movement and cognitive performance in elderly subjects but no improvement from short-term vitamin therapy: a placebo-controlled randomized study. The American journal of clinical nutrition, 81(5), 1155-1162.
Clarke, R., Harrison, G., & Richards, S. (2003). Effect of vitamins and aspirin on markers of platelet activation, oxidative stress and homocysteine in people at high risk of dementia. Journal of internal medicine, 254(1), 67-75.
Tucker, K. L., Qiao, N., Scott, T., Rosenberg, I., & Spiro, A. (2005). High homocysteine and low B vitamins predict cognitive decline in aging men: the Veterans Affairs Normative Aging Study. The American journal of clinical nutrition, 82(3), 627-635
© 2016 Nootrobox, Inc. All Rights Reserved.
For informational purposes only. These statements have not been evaluated by the FDA. Products are not intended to diagnose, treat, cure, or prevent any disease.