Individuals who frequently consume multiple energy drinks daily might be at risk of a harmful overdose, caution medical experts. Interestingly, it’s not the sugar or caffeine causing concern, but rather vitamin B6, which is included to enhance energy and focus.

Found naturally in fish, poultry, potatoes and avocados, B6 is essential for brain and nerve health in small amounts.

Gradually, excessive consumption of vitamin B6 could lead to peripheral neuropathy, a distressing condition characterized by tingling, numbness, and a burning sensation in the extremities. In rare cases, it might even impact heart health and circulation.

Vitamin B6, often labeled as pyridoxine, pyridoxal, or pyridoxamine, is a common additive found in numerous products, including medications, multivitamins, energy drinks, and diet shakes.

However, the Therapeutic Goods Administration (TGA) in Australia recently reported an increase in cases of vitamin B6 toxicity, confirming 170 instances and suspecting that many more might remain undiagnosed.

The NHS advises a daily intake of 1.2mg of vitamin B6 for women and 1.4mg for men, cautioning against exceeding 10mg without doctor’s approval. For instance, a 250ml can of Red Bull contains 4.5mg, and a 500ml Monster Energy can has about 4mg. Consuming just three cans a day might result in exceeding the stated ‘safe’ threshold.

NHS guidance notes that symptoms of toxicity usually appear above 200mg, but admits the risks are ‘unclear’ between 10mg and 200mg.

The TGA has issued a broader warning, suggesting that nerve damage could occur at intakes of less than 50mg a day. Similarly, the European Food Safety Authority has evidence suggesting that 50mg daily can harm certain individuals, recommending a much lower safe upper limit of 12mg per day.

Professor Alan Boobis, a toxicology expert at Imperial College London, emphasized that it is unlikely that energy drinks or supplements alone would push intake over the threshold.

Instead, he warned the real risk comes from overconsumption. Often without realising, people may be getting vitamin B6 from multiple sources at once. ‘If there is regular use of both over a period of time,’ he said, ‘nerve damage that can lead to peripheral neuropathy may develop’.

And GP Dr Giuseppe Aragona said it is this cumulative effect that ‘catches people out’. He explained: ‘If you add in B6 from multivitamins or fortified foods, it can add up without someone realising.

‘So while an occasional energy drink is unlikely to do harm, drinking multiple cans every day could increase the risk of toxicity, especially over time.’

He added that because the symptoms can ‘overlap with conditions like diabetes, B12 deficiency or nerve problems’, some ‘cases could go unrecognised,’ he warned, adding that it’s plausible that hundreds of people in the UK could be experiencing early nerve symptoms without realising the cause’.

According to Dr Jack Ogden, a GP in Bristol, symptoms can include burning sensations in the legs, difficulty with coordination and fine motor skills, sensitivity to touch, fatigue and mood or concentration problems.

Professor Boobis added: ‘It takes time for nerve damage to develop, typically a few months.’

Pharmacist Deborah Grayson said: ‘There is certainly a very real risk regarding the levels of vitamin B6 in energy drinks, particularly when combined with other sources.

‘While vitamin B6 is essential, the manufactured forms can cause health problems when consumed in excess.’

This was the harsh reality for one 23-year-old Australian woman who recently revealed her experience in a TikTok video posted under the handle @Kate4102.

She explained how she initially dismissed her troubling symptoms of dizziness, muscle cramps and brain fog, believing they were neurological problems linked to back surgery she had undergone.

But after hearing about a GP with a severe case of B6 toxicity on the news, she began to question whether her own symptoms could be down to the same issue.

And she finally decided to seek medical advice after noticing a bald patch on her head.

A blood test confirmed that she had dangerously high levels of vitamin B6 in her system – so severe she ‘nearly had to have kidney dialysis’. She said energy drinks were her ‘main culprit at one point’.

Her levels have since declined, but the episode has had a lasting impact on her day-to-day life. ‘I couldn’t drive for a while. I couldn’t work properly.

‘I couldn’t even walk properly because I felt so dizzy – like I was on a boat,’ she said.

Red Bull and Monster were approached for comment.