Recent media coverage of vitamin B6 consumption is an opportunity to highlight fact from fiction and explain the role of this essential vitamin in our body, key food sources, and risk of overconsumption from supplements.
What is Vitamin B6?
Vitamin B6 (also called pyridoxine) is an essential nutrient you get from food or supplements. Once inside the body, it’s converted into its active form, pyridoxal 5′-phosphate (PLP), which helps run over 160 different chemical reactions. These include producing energy from food, building haemoglobin for red blood cells, supporting immune function, and regulating inflammation.
Even though it’s crucial for health, vitamin B6 deficiency is rare, more likely to occur in older adults, people with certain chronic illnesses, or those with poor diets. Human gut micoflora synthesise vitamin B6 which can make a significant contribution to a person’s vitamin B6 intake and may be an additional factor for why dietary vitamin B6 deficiency is rare (1).
Food sources
Vitamin B6 is found in foods such as meats, especially organ meats, poultry, fish, eggs, bananas, and potatoes. In Australia and New Zealand. Vitamin B6 is permitted to be added to various food items including bread, breakfast cereals, cereal flours, pasta, extracts, formulated foods and beverages. The maximum permissible amount is 0.4 mg (equates to 25% RDI) per reference quantity (2). See table.
Food
Maximum claim amount (mg) & %RDI claim
Reference quantity
Cereal & cereal products e.g. biscuits, flour, pasta
0.4mg (25% RDI)
35g
Bread
50g
Breakfast cereal
A normal serving
Extracts eg yeast, meat, vegetables
5g
Formulated beverages
600ml
Formulated caffeinated beverages (known as energy drinks) can contain up to 10mg of vitamin B6 in a daily maximum amount of 600mL (3). This permitted amount is five times less than the upper limit of 50mg/day noted by the NHMRC (1).
In comparison to foods, supplements of vitamin B6 (listed as pyridoxine, pyridoxine hydrochloride, pyridoxal 5-phosphate, and pyridoxal 5-phosphate monohydrate) provide significantly higher amounts. Currently, vitamin B6 supplements that contain up to 100mg are available to be sold over the counter. The Therapeutic Goods Administration recently released an “interim decision” on vitamin B6, which proposes that products with more than 50mg per day should be up-scheduled to Schedule 3 (Pharmacist Only Medicine) (4). This cautious approach would mean any vitamin B6 supplement containing more than 50mg would need to be kept behind the counter at the pharmacy, and sold after consultation with a pharmacist. Vitamin B6 supplements with 50mg or below would continue to be available over the counter, under the new proposal (4).
How much is needed?
Not everyone needs the same amount of vitamin B6. Factors like age, health status, medication use, and genetics can affect how much is needed. In some health conditions, higher amounts may be beneficial, but self-supplementation in high doses should be avoided without professional advice.
From clinical studies, research shows some uses have clear biochemical explanations and have strong evidence such as treating rare genetic disorders (epilepsy syndromes), while evidence is mixed for treating sides effects of pre-menstrual symptoms, morning sickness, and there is only weak evidence for cardiovascular disease. High doses and/or prolonged use has been linked with peripheral neuropathy at high doses (>500 mg/day (4)).
The general recommended daily intake (RDI) (1) is:
Adults 19–50: 1.3 mg/day
Adults over 50: 1.5 mg/day (women), 1.7 mg/day (men)
Pregnancy: 1.9 mg/day
Lactation: 2.0mg/day
These amounts can be easily achieved through eating a variety of foods as part of a healthy diet such See examples below
Example combinations to meet ~1.7 mg:
Option 1 – Chicken + Potato + Banana
100 g roast chicken breast → 0.5 mg
1 medium baked potato → 0.6 mg
1 medium banana → 0.4 mg Total: 1.5 mg (add a small handful (1/4 cup) of sunflower seeds for +0.3 mg)
