Low levels of Vitamin B6 may correlate with low testosterone levels, suggesting a possible T-supportive role.
Vitamin B6 is an essential vitamin with many important functions in the human body. Early animal evidence suggests it may play a role in maintaining testosterone levels. As a T-Booster, Vitamin B6 has been theorized to work by:
- Blocking T-binding activity. Vitamin B6 appears to have some influence on cell receptors that are involved with binding and inactivating testosterone.
Overview
Vitamin B6, also known as pyridoxine, pyridoxal and pyridoxamine, is an essential vitamin involved in over 100 different enzyme reactions in the body. B6 serves a particularly important role in the synthesis and breakdown of proteins and amino acids, as well as hemoglobin production and immune function. In addition, two of its coenzyme forms—P-5-P and PMP—are important for proper functioning of amino acids, sugars, and fats.1
Vitamin B6 is water-soluble, which means that the body cannot store it, and any unused B6 is flushed out in urine. This means that vitamin B6 has to be continually taken through diet. Thankfully, B6 is found in many different foods, including meat, bananas, avocados, nuts, whole grains, corn, and many other vegetables and fruits. It is also often added to breakfast cereals.2
Vitamin B6 has also been proposed as a potential testosterone booster by supplement companies. In particular, one blend of zinc, magnesium, and vitamin B6—known as ZMA—has been marketed as a natural way to increase testosterone.3
However, clinical evidence to support these claims remains elusive, leading us to regard B6 as a speculative T-Booster that seems to make sense as a smaller component of more extensive testosterone supplement stacks.
How Vitamin B6 Might Help Testosterone
Thus far, researchers have suggested two theoretical bio-activities of vitamin B6 that may be relevant to testosterone support:
Regulating Cell Receptors that Bind Hormones
It appears that vitamin B6 in its P-5-P form (also called PLP) may affect the function of specific receptors in cells, whose job is to bind to and activate various hormones, including testosterone. A number of studies found that increased PLP concentrations can reduce the activity of these receptors, thus making cells less responsive to hormones. Meanwhile, the reverse effect was found when intracellular PLP concentrations were decreased. While this effect may be useful for several sex hormone-related conditions, it is currently unclear whether this mechanism can have any benefit for boosting testosterone levels.456
Possibly Assisting with Testosterone Synthesis
It’s also possible that vitamin B6 is somehow directly involved in the synthesis or metabolism of testosterone, perhaps as a raw material or signalling compound — since restricting B6 intake appears to reduce testosterone levels. Nevertheless, these findings are limited to a single study in rats and have not been reproduced in humans.7
Research
Animal Research
The few animal trials of vitamin B6’s impact on testosterone levels show mixed results.
Vitamin B6 depletion appears to significantly reduce blood testosterone in rats
The goal of this study was to examine the interaction between Vitamin B6 and testosterone in male rats. The animals were fed either a normal or a vitamin B6-free diet for 4 weeks. Blood testosterone levels in the B6-free group dropped by over 70% compared to the normal diet. Researchers offered two possible explanations for this drop: either testosterone synthesis is reduced when vitamin B6 is deficient, or it is removed faster from the blood.
- The researchers concluded that “These results show significant effects of vitamin B, nutritional status, at a level of moderate deficiency that is likely to be encountered in a significant proportion of the population even of developed countries, on the circulating concentrations of testosterone”8
High-dose vitamin B6 injections do not appear to affect testosterone levels in rats
This study looked at the effects of high-dose pyridoxine injections on sperm production and male sex organs in rats. Male rats were divided into 5 groups: control, pyridoxine 125 mg/kg, pyridoxine 250 mg/kg, pyridoxine 500 mg/kg, and pyridoxine 1000 mg/kg injected daily 5 days a week for 2 or 6 weeks. The study did not find any significant changes in testosterone levels in any of the pyridoxine groups.
- The researchers concluded that “Plasma testosterone concentration did not significantly alter in all the exposed groups”9
Human Research
Human studies of vitamin B6 as a testosterone booster have yet to show any benefit, with evidence limited to research involving B6 as part of a ZMA complex:
Vitamin B6-containing supplement ZMA does not appear to boost testosterone in healthy men
The study examined whether there was any truth to the claims that the vitamin B6-containing supplement ZMA could increase testosterone levels. Fourteen physically-active men were given either placebo or ZMA (30 mg zinc, 450 mg magnesium, 10.5 mg vitamin B6) daily for 56 days in capsules. The researchers did not find any significant differences in blood testosterone levels between the two groups.
- The researchers concluded that “the advertised testosterone-increasing effect of ZMA supplementation could not be confirmed in the present trial”10
Dosage Notes
- Vitamin B6 RDA for adults age 19-50: 1.3 mg
- RDA for men over age 51: 1.7 mg
- RDA for women over age 51: 1.5 mg
- No current recommendations exist for the appropriate dosage of Vitamin B6 for boosting testosterone.
- Testosterone stacks that include B6 will typically dose it in the range of 2 mg – 10 mg
Side Effects
Pyridoxine may rarely be linked to mild, transient side effects, including digestive symptoms such as nausea and stomach pain, as well as headache and sleepiness.
Available Forms of Vitamin B6
- Vitamin B6 is typically sold as pyridoxine hydrochloride in tablet form by itself, or as part of a vitamin B6 complex, or a multivitamin.
- It is also sold as part of the trademarked ZMA blend of zinc, magnesium aspartate, and pyridoxine HCL.
- Vitamin B6 in the “activated” P-5-P form appears to hold greater potential for assisting with testosterone
Supplements in Review Recommendation
- Vitamin B6 as P-5-P, 7.5 mg
Vitamin B6 may play a minor role in supporting testosterone. This assertion is mostly based on animal research that shows when B6 levels are low, T levels follow suit. While this evidence is early, it seems to indicate a B6-T link. As a standalone testosterone supplement, B6 would be questionable — but since it is effective in small dosages, it makes sense to include as an “insurance” nutrient within a larger testosterone-boosting stack.
P-5-P is a more active & potent form of B6. It is more expensive, but we think it’s worth it to use the P-5-P form to realize any potential testosterone-boosting effects of Vitamin B6. We think the 7.5 mg is a good P-5-P dosage starting point for T; it’s a little less than the max amount seen in T-booster stacks — but keep in mind this is theoretical at best, since B6 dosages for testosterone are not yet backed by human clinical research.
References
I liked your article but you seem to have some inconsistencies
RE: Animal Research B6 and testosterone.
Study you refer to: #7 https://www.ncbi.nlm.nih.gov/pubmed/6727359
You say that “Blood testosterone levels in the B6-free group dropped by over 70% compared to the normal diet.” However, I could not find any mention of this in the study your refer to. You also say:Researchers offered two possible explanations for this drop: either testosterone synthesis is reduced when vitamin B6 is deficient…… yet the research you refer to explicitly says: “in both intact and 24-h castrated animals vitamin B6 deficiency resulted in a significant increase in the uptake of [3H]testosterone into the prostate.”
https://www.ncbi.nlm.nih.gov/pubmed/6727359