Vitamin B6:
- One human study showed a single 300mg dosage of B6 exerts ‘a hypothalamic dopaminergic effect’ which causes a ‘significant decrease of plasma prolactin’(1);
- Another found that 300mg of B6 taken twice a day by 10 normal women lowered prolactin levels and slightly but significantly raised growth hormone levels. The authors concluded: ‘The effect of vitamin B6 is likely to be mediated by dopaminergic receptors at hypothalamic level’(2);
- Another study found B6 to significantly reduce ‘opioids-induced hyperprolactinemia’(3);
- This study on men found that ‘Pyridoxine (B6) suppresses the rise in prolactin and increases the rise in growth hormone induced by exercise’(4);
- And a study on male rats found that, ‘Pyridoxine hydrochloride significantly suppressed the chlorpromazine-induced prolactin rise (p less than 0.01). However, the suppression was significantly less than that produced by bromocriptine (p less than 0.01)’(5).
- Effects of pyridoxine hydrochloride (vitamin B6) on chlorpromazine-induced serum prolactin rise in male rats. - PubMed - NCBI
Ways around these side effects:
One way to avoid the ‘finger tingling’ that high dose B6 can cause is to take the activated form of B6 called Pyridoxal-5-Phosphate (P5P) – the activated form of B6 does not cause these nerve issues.
In fact, the reason that high dose B6 causes nerve problems is that the body can’t always process very high B6 doses properly and this creates a deficiency of the active form of B6, P5P.
Recommended dosage:
To lower prolactin levels I would recommend you take 50 to 200mg of P5P a day, in divided doses. If you want to take regular B6, which as I’ve mentioned can sometimes cause minor side effects, take 300 to 1000 mg per day in divided doses.
Read the label before you buy B6 because the Pyridoxine Hydrochloride type of B6 (in most supplements) has been shown to be a prolactin inhibitor but Pyridoxal hydrochloride has been shown to be ineffective at lowering prolactin (6)
Vitamin E
Like B6, vitamin E is a powerful natural prolactin inhibitor that is dirt cheap and rarely causes side effects.
Vitamin E has been less thoroughly studied than B6 in relation to lowering prolactin, but it has proved successful with bodybuilders on steroids trying to keep their prolactin levels from rising.
One study in 1992 looked at ‘The effect of vitamin E therapy on sexual functions of uremic patients in hemodialysis’:
‘Twenty-four uremic patients on hemodialysis who had never been treated with vitamin E or related drugs and 12 control patients with normal renal function were studied. Hemodialysis patients were randomly divided into two groups; 12 were treated with oral vitamin E (300 mg/day) for eight weeks and 12 uremic patients and 12 controls were given placebo.
Serum vitamin E, prolactin, FSH, LH, and free testosterone levels were measured in all patients before and after treatment.
After the vitamin E treatment serum prolactin levels were significantly decreased (50.8 vs 15.4 ng/ml, p < 0.01). Vitamin E levels were significantly increased (1.11 vs 1.22 mg/dl, p < 0.05). Serum FSH, LH and free testosterone were not affected. In the other two groups there were no significant changes.’
The authors concluded:
‘These results show that vitamin E treatment lowers prolactin levels in uremic hemodialysis patients. This might be due to inhibition of central prolactin secretion. Vitamin E inhibits pituitary gland hypertrophy in vitamin E-deficient rats’(7).
Another study on one patient reinforces vitamin e as being an effective prolactin inhibitor:
‘Vitamin E is one of the most important lipid-soluble antioxidant nutrient. Severe vitamin E deficiency (VED) can have a profound effect on the central nervous system. VED causes ataxia and peripheral neuropathy that resembles Friedreich’s ataxia.
We report here a patient presenting this syndrome, but also a prolactin and FSH adenoma. Both the neurological syndromes and the adenoma regressed after treatment with alpha-tocopherol. Although, the presence of the prolactinoma in this patient may not be related to his vitamin E deficiency, alpha-tocopherol treatment seems to be beneficial and might usefully be tested in patients with hypophyseal secreting other forms of adenoma.’(8)
Vitamin E has long been known as one of the most important vitamins for male fertility, and it seems likely that one of the mechanisms by which vitamin e improves fertility is by lowering prolactin levels.
It is also suggested by researchers that vitamin e protects against free-radical damage to the unsaturated fatty acids in the sperm membrane, improving sperm motility and fertility.
