The B vitamins are eight water-soluble vitamins that are found in foods like potatoes, bananas, lentils, tempeh, liver, tuna and brewer’s yeast. Water soluble vitamins are not stored by the body so these are needed more frequently in the diet than fat soluble vitamins. The B vitamins help the body convert food (carbohydrates) into fuel (glucose), which is used to produce energy. They also help the body use fats and protein. B complex vitamins are needed for healthy skin, hair, eyes, liver and healthy functioning of the nervous system.
Vitamin B6 (pyridoxine)
Vitamin B6 helps the body make several chemicals that carry signals from one nerve cell to another (neurotransmitters). It is needed for normal brain development and function. It helps make the hormones that influence our mood (serotonin and norepinephrine) and our sleep and wake cycles (melatonin) amongst many other uses1.
B6 and breastfeeding
A breastfeeding mother’s diet will normally provide plenty of B6 which will also meet her baby’s needs for this vitamin via her breast milk. Poultry, fish, eggs, cereals and certain vegetables are good sources of this vitamin and there is a comprehensive list of foods here.
What is the recommended amount for a breastfeeding mother?
The National Institutes of Health, Office of Dietary Supplements states the Recommended Dietary Allowance (RDA) for vitamin B6 for a woman is 1.3 mg/day rising to 1.9 mg/day in pregnancy and to 2 mg/day in lactation2. Hale and Rowe of Medications & Mothers’ Milk Online, 2018 note that most prenatal vitamin supplements contain 10 mg/day and excessive doses are not recommended as pyridoxine readily moves into breast milk and levels in milk will increase with maternal intake.
How much vitamin B6 is excessive?
The National Institutes of Health Vitamin B6 Fact Sheet indicates that a Tolerable Upper Intake Levels for Vitamin B6 is 80-100 mg/day. Anyone receiving higher levels for medical treatment should be under the care of their health professional 3.
What if I am deficient in B6?
A deficiency in vitamin B6 is unusual and would usually be associated with deficiency in other micronutrients. In Breastfeeding and Medication Wendy Jones recommends that B6 be taken as part of a multivitamin supplement rather than in large amounts on its own.
Can B6 supplements help postnatal depression or pre-menstrual syndrome?
Wendy Jones says that while deficiency of B6 is rare, supplements of B6 are sometimes suggested for postnatal depression and pre-menstrual tension, however there is no evidence that this is helpful compared with placebo and excessive doses could be harmful (may cause sensory neuropathy)4.
B6 and vasospasm
A vasospasm is a painful spasm or narrowing of blood vessels preventing blood from getting to an area. In some breastfeeding mothers and those with Raynaud’s Phenomenon this can happen in the nipple. See Nipple Vasospasm and Breastfeeding for more information on this painful condition. Canadian paediatrician Jack Newman suggests trying vitamin B6 supplements as one of several treatments for Raynaud’s Phenomenon:
We usually recommend 200 mg a day as a single dose for four days and 25 to 50 mg a day as a single dose from then on. If the vasospasm returns after lowering the dose, we recommend resuming the higher dose and every so often trying to lower it or stop it altogether. Although some suggest that vitamin B6 can reduce milk supply, I have not seen this even when mothers took 200 mg a day for many weeks. In our clinic we recommend vitamin B6 multi complex, although this combination of B vitamins has not been shown to be any better than the vitamin B6 alone.
Although other sources also refer to higher levels of vitamin B6 for helping Raynaud’s Phenomenon 5, the InfantRisk Centre urges caution stating that vitamin B6 has been associated with seizures at doses of 300 mg/day or more and doses above 600 mg/day could decrease a mother’s milk supply 6.
Can B6 dry up breast milk?
There are many mentions online about taking B6 to dry up breast milk. Very high maternal supplements of B6 may suppress prolactin levels and cause a fall in breast milk production though not all studies have found this effect and there does not seem to be much evidence. It may be worth bearing this in mind if you do notice a drop in your supply and are taking a B6 supplement. If you are looking for ideas to help with drying up breast milk see How to Stop Breastfeeding and, as very high supplements of B6 could be harmful, discuss with your GP before taking high doses of this vitamin. Thomas Hale 7 quotes several concerns to watch out for when taking B6 including sedation, sensory neuropathy (sensory disturbances), ataxia (e.g. problems with co-ordination, balance and speech), nausea, and seizures at high intravenous doses.
Brewer’s yeast for milk supply?
Brewer’s yeast is a good source of B vitamins including B6 (note: brewer’s yeast does not contain B12). Some breastfeeding websites, e.g. Jack Newman’s website, mention taking brewer’s yeast to increase a breastfeeding mother’s milk supply.
Nursing Mother’s Herbal is a herbal reference guide and has this to say about Brewer’s yeast:
[Cheryl Renfree] recommends adding brewer’s yeast for B vitamins, iron and protein. Many mother’s have found brewer’s yeast to be helpful not only for building their milk supply but also for combating fatigue, depression and irritability.
Note, the author also cautions that brewer’s yeast can sometimes make a baby colicky:
Avoiding certain foods is thought to prevent or help treat colic. A baby can become colicky after his mother eats a certain food, but this trigger food may vary from mother to mother. For some it may be green beans or tomatoes. For others brewer’s yeast, vitamins with iron or fluoride, or artificial sweetners. Mothers who smoke or drink large amounts of caffeine tend to have colicky babies. If you can eliminate trigger foods and substances from your diet you should see positive results within a day or so, although the full effect may not be apparent for a week or two.
B vitamins for thrush?
Some resources refer to taking B vitamin supplements to help treat a persistent fungal infection such as thrush on nipples. Note that brewer’s yeast is not recommended as a source of these vitamins during a thrush infection, as all potential sources of yeast should be avoided at this time 8.
A breastfeeding mother will normally get plenty of vitamin B6 naturally in her healthy diet. Recommended Dietary Allowance for vitamin B6 in breastfeeding women is 2 mg/day and daily prenatal supplements usually contain 10 mg. Vitamin B6 supplements are sometimes recommended for helping nipple vasospasm. There are mixed reports about high doses of vitamin B6 reducing a mothers’ milk supply but other harmful side effects have been noted at high levels. Always discuss with your health professionals before taking high medicinal doses of this vitamin.