Complaints & connections · borters.ch
Deficientia vitamini B6
With B6 too little and too much do the same thing — tingling, numb feet. So it is measured before it is taken.
Also known as: vitamin B6 deficiency · pyridoxine deficiency
Open in the tool — with search and all the links →This compilation is for information and replaces neither medical diagnosis nor treatment. If you have symptoms, see a doctor.
Vitamin B6 takes part in over a hundred reactions, above all in protein and nerve metabolism, in making messengers and in building the red blood pigment. A pure dietary shortage is rare, because B6 is widely present in meat, fish, potatoes, bananas and wholegrain. More often medicines and illnesses are the cause: isoniazid against tuberculosis, penicillamine, hydralazine, along with regular alcohol, coeliac disease, chronic kidney disease and dialysis. Signs are tingling and numbness in hands and feet, reddened scaly skin around nose, eyebrows and mouth, cracked corners of the mouth, a sore tongue, irritability and confusion; in an infant seizures can occur. This dossier, though, has a peculiarity that sets it apart from every other vitamin: with B6, too much is in everyday life the commoner problem. High doses over months — often unnoticed in nerve, mood and magnesium preparations or in a B complex — cause nerve damage that feels exactly like the shortage: tingling, numb feet and an unsteady gait. So anyone taking B6 because of tingling can make the tingling worse with it. Which is why it is measured before it is taken.
B complex, nerve and mood products, magnesium with B6, energy drinks: the milligrams add up. Laying all the packets side by side once and adding the numbers often answers the question straight away.
Because shortage and excess make the same picture, only the value says which way it goes. A supplement on suspicion can do harm here.
The nerves usually recover after stopping, but slowly — over months. The earlier it is noticed, the more complete the recovery.
Fish, poultry, potatoes, bananas, chickpeas, wholegrain and nuts supply plenty. In this form an oversupply is not possible.
Diabetes, B12 deficiency, thyroid, alcohol and trapped nerves are far commoner. B6 belongs in the list but rarely stands alone.
That is the one case in which it is taken preventively — at a fixed, low dose and as part of the treatment plan.
B6 fills a store that builds over weeks; signs such as cracked mouth corners and tingling improve over four to twelve weeks. Here the amount matters exceptionally in both directions: too much B6 over months — from about fifty to a hundred milligrams a day — itself causes nerve damage, which recedes slowly and not always completely. Isoniazid, penicillamine and hydralazine lower the level and are therefore combined with B6.
The daily requirement is about 1.3 to 1.7 milligrams. The store lasts two to six weeks without intake. Here the upper limit is the actual point: from about fifty to a hundred milligrams a day over months, a nerve damage of its own arises, which after stopping recedes over months to years and not always completely. Many combined preparations for nerves and skin contain far more than the requirement.
This is the hint that matters here. If complaints increase while taking a supplement, the dose is the first suspect — not the shortage.
Together with cracked corners of the mouth and a sore tongue this is the typical combination of the shortage — it looks like a stubborn seborrhoeic eczema.
The dose is printed small on the back and adds up when several products come together. This is exactly where the oversupply arises, without anyone intending it.
Here the shortage is planned for: B6 is routinely given alongside this treatment, precisely to prevent the nerve damage.
Alcohol disturbs uptake and conversion into the active form at once. In everyday life it is the commonest cause of a genuine shortage.
What a deficiency makes visible on the body — skin, nails, tongue, eyes and nerves. The signs are unspecific: they show where to look, they prove nothing.
The active form is what is measured. The value answers both questions at once — whether there is too little and whether too much has been taken.
Rises when B6 is short — but also with B12 and folate deficiency. It shows that a gap has reached the metabolism, not which one.
A marked B6 shortage can cause an anaemia with strikingly small red cells — unlike B12 and folate, where they grow too large.
With chronic kidney disease and on dialysis B6 is lost. That is one of the commonest medical causes and is rarely thought of.
B6 is the helper for building serotonin, dopamine and GABA — without it the making of all three stalls. That is why a deficiency can cause irritability, low mood and, in the extreme, seizures.
On the pill a lower B6 level has been measured. The difference is small and mostly without consequence — but it explains why B6 is so often offered for PMS.
B6 slightly dampens prolactin release — hence its old use for stopping breastfeeding. It only worked at amounts that are no longer given today, because of the nerve damage.
B6 is in meat, fish, potatoes, bananas and wholegrain — a deficiency from diet alone is rare. Certain medicines are more often the cause. And in the other direction: above 50 mg a day over months B6 itself damages nerves.