1 Ingredient in Your Multivitamin May be Hurting You More than Helping

It’s not what you’re missing—it’s what you’re unknowingly overdoing

Author

My Longevity Experiment
April 05, 2025

Understanding the Risks of Vitamin B6 Supplements

Recent reports have raised concerns about severe reactions in individuals taking over-the-counter vitamin B6 supplements. While vitamin B6 is a vital nutrient, excessive intake—particularly through supplementation—can result in nerve damage, leading to symptoms such as numbness, tingling, and difficulty walking.

In some cases, affected individuals were unaware that the supplement they were using even contained vitamin B6.

What is Vitamin B6?

Vitamin B6, also known as pyridoxine, refers to a group of six related compounds with similar chemical structures. It is an essential nutrient, meaning the body cannot synthesize it and must obtain it from the diet.

Adults between the ages of 19 and 50 require 1.3mg per day. This requirement increases with age and during pregnancy or breastfeeding. Common dietary sources include animal products such as meat, dairy, and eggs, as well as plant-based foods like bananas, potatoes, spinach, and kale.

However, the vitamin B6 present in food is inactive. The liver converts it into an active form called pyridoxal-5′-phosphate (PLP), which is responsible for over 140 cellular functions, including protein metabolism, red blood cell formation, blood sugar regulation, and brain support.

Vitamin B6 is also associated with reduced inflammation and cancer risk, making it an important contributor to overall health.

Widespread Supplementation

Despite its availability in food, vitamin B6 is frequently added to supplements, multivitamins, and energy drinks. Products such as Berocca, and supplements labeled for magnesium or zinc, often contain added B6—sometimes without clear labeling—leading consumers to unintentionally exceed safe limits.

Should We Be Concerned About Toxicity?

Vitamin B6 toxicity is extremely rare through diet alone, especially in the absence of conditions that affect nutrient absorption, such as coeliac disease. B vitamins are water-soluble and typically excreted in the urine when consumed in excess.

However, in some individuals, high levels of B6 from supplements accumulate in the bloodstream and lead to a condition called peripheral neuropathy. This occurs when sensory nerves are damaged, disrupting communication between the body and central nervous system.

The condition can present as numbness, tingling, and balance problems. Though symptoms may improve upon discontinuing the supplement, full recovery is not guaranteed. The exact mechanism remains unclear, though it is believed that excess vitamin B6 may interfere with GABA, a neurotransmitter that transmits signals in sensory nerves.

What Counts as Too Much?

Toxicity is almost exclusively linked to high-dose supplements. Prior to 2022, only products containing more than 50mg of vitamin B6 were required to carry a warning label. Following a review by the Therapeutic Goods Administration (TGA), this threshold was lowered to 10mg per dose.

The TGA also reduced the maximum allowable daily amount in supplements from 200mg to 100mg. This decision followed 32 reports of peripheral neuropathy, with two-thirds of those cases involving individuals consuming less than 50mg of vitamin B6 daily.

“The risk varies between individuals and a lot is unknown,” the TGA stated. Their investigation was unable to determine a specific safe dosage or duration of use, nor did it identify consistent risk factors among those affected.

Are B Vitamins Still Safe?

The perception that B vitamins are inherently safe has contributed to their widespread use. While vitamin B6 is necessary, too much can cause harm. The updated regulations aim to reduce risk and improve consumer awareness.

Ongoing research is focused on why some people develop neuropathy from relatively low doses. Possibilities include varying effects from different B6 compounds or genetic predispositions that increase sensitivity.

Practical Guidance for Supplement Users

Most individuals do not need to supplement with vitamin B6, particularly if they maintain a diverse and balanced diet. However, many reports to the TGA revealed that B6 was often added to products not clearly marketed for it.

Consumers are encouraged to read labels carefully, especially when combining supplements. A single multivitamin is unlikely to cause toxicity but combining it with additional supplements such as magnesium or zinc may lead to cumulative B6 intake that exceeds recommended levels.

Awareness of symptoms such as tingling, numbness, or foot and hand pain is essential. These could be early signs of peripheral neuropathy and should be taken seriously. “Most importantly, if you need advice, you should talk to your doctor, dietitian or pharmacist.”

Your Call to Action for Understanding Vitamin B6 Supplement Risks

To protect your long-term health, rely primarily on whole foods to meet your vitamin B6 needs. Be cautious with supplements, especially if you are using more than one product. Always read ingredient labels and consult a healthcare provider if you’re uncertain. Pay attention to early warning signs like numbness or tingling and respond quickly if they arise. Responsible supplementation begins with awareness and informed choices.

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