What is Vitamin B-6 P5P (Pyridoxal-5-Phosphate )
Updated Jun. 20th, 2023
What is it?
The vitamin pyridoxine is commonly known as vitamin B6, and is involved as a cofactor in a number of different enzymatic processes in the body. Active B6 in its coenzyme form serves in more functions in the body than any other single nutrient. It is particularly important for protein metabolism, and it also plays a role in blood sugar regulation. B6 can be used to treat anemia, allergies, arthritis, asthma, cancer, kidney stones, pregnancy-related nausea and multiple sclerosis (MS). For more information on the many benefits of vitamin B6 supplementation, please click here.
Deficiency
A lack of sufficient B6 can appear as confusion, depression, irritability and mouth and tongue sores. It can also present as anemia, headaches, flakey skin, and even as carpal tunnel syndrome. Because of the fortification of processed foods, vitamin B6 deficiency is rare in North America.
Absorption
Vitamin B6 is absorbed in the small intestine and is dephosphorylated prior to absorption. This means that most B6 taken in its active form (P5P / PLP) will be converted back to its pyridoxal form prior to active absorption in the gastrointestinal tract. Once absorbed, it is converted back to P5P, its active form. Some people may lack this conversion enzyme and may benefit from higher doses of directly supplemented P5P that will bypass the transporter molecule and be absorbed through diffusion. Most people can benefit from supplementation of either form of vitamin B6.
Supplementation
P5P can be found in a number of different supplements including some B complexes, as well as PMS, cardiovascular, brain health, and mood balancing formulas. In general, it can be dosed at the same levels as pyridoxine. Thus, between 50 and 100mg per day is generally sufficient. For more information on dosing.
Important Information
B6 is depleted by antidepressants, estrogen, oral contraceptives, some antibiotics, and alcohol. Cortisone and diuretics block the absorption of B6. Diets high in protein require a larger B6 intake to allow for proper digestion and utilization. Prolonged excessive intake of B6 (1-6g per day for more than a year), can result in sensory neuropathy and loss of control of bodily movements. Doses exceeding 400mg per day are not recommended. Parkinson's patients on dopamine therapy should not supplement with B6, and diabetics should monitor their blood sugar levels during supplementation as their insulin dosage may need to be lowered.
What I learned in organic chemistry is that the B vitamins tend to be really important cofactors for important enzymes, which explains the enormous role that these vitamins play in the healthy functioning of the human body. This was an excellent overview and again, as always, I really like the nutritional information section you provie at the end of the article-this is so pragmatic and helps people to take action after learning STAT while also maintaining safety and following good protocol. Thanks for the B-eutiful B vitamin article (and please do excuse the terrible pun: I had a long week in lab!!)
Hello Rachel,
Thank you for sharing your knowledge and experience with b vitamins, sharing is caring! Happy to see you've been enjoying our articles on the b vitamins, there are a lot of them! Thank you for mentioning you like the quick facts tables in our articles, they're a great summary and take aways for readers to put what they've learned into action. You can learn about the differing b vitamins in their own articles as well as b vitamins as a whole, which can be found as a b complex formula and this keeps the b vitamins in their delicate ratio, https://www.youtube.com/watch?v=C02cbvdN8zs
Stay healthy & well!