Image: AP

A 50-year-old construction worker who consumed four to five energy drinks a day for three weeks was recently diagnosed with acute hepatitis, a condition characterized by liver inflammation. While not the first case of its kind, the incident points the largely ignored dangers of excess niacin consumption.


A new case report published in the British Medical Journal highlights the need for consumers to be aware of all the ingredients found in popular food and drink items, and to avoid the over-consumption of dietary supplements. Doctors who treated the unnamed man believe his sudden bout of hepatitis was caused by his excessive energy drink consumption, which included the ingestion of copious amounts vitamin B3, also known as niacin.

As a construction worker, the man began to consume energy drinks to help him power through his labor-intensive workday. Aside from hitting the energy drinks with unusual fervor, he didn’t make any other changes to his eating and drinking habits. Soon afterwards, the man started to become unusually fatigued, and he began to experience abdominal pain. When this turned to nausea and vomiting, he figured he had the flu—but the man became particularly alarmed when he developed dark urine and jaundice (his skin was turning yellow). Wisely, he went to the emergency department.


A physical examination affirmed the jaundice and right upper abdominal tenderness, while lab tests revealed high levels of transaminases—liver enzymes indicative of damage and evidence of chronic hepatitis C infection. A biopsy of the liver confirmed he had severe hepatitis.

Monster Energy contains 200 percent of the daily recommended intake of niacin. (Image: Flickr/homard)

Doctors who treated the man believe the hepatitis was triggered by his excessive energy drink consumption, with niacin being the key ingredient. Interestingly, the patient’s intake was around 160 to 200 milligrams (mg) daily, which is considered below the level expected to cause toxicity (a similar case was reported before, but the patient consumed 300 mg of niacin daily!). The problem, say the doctors, was that toxicity arose as a result of an accumulation effect; each bottle of his energy drink contained 40 mg of niacin, or 200 percent of the recommended daily value.



The brand consumed by the patient wasn’t listed, but energy drinks with added niacin include Monster, Rockstar, and Red Bull. The patient was told to discontinue consumption of all energy drinks, and was advised to avoid any similar niacin-rich products in the future.


“As the energy drink market continues to rapidly expand, consumers should be aware of the potential risks of their various ingredients,” conclude the authors in the case report. “Vitamins and nutrients, such as niacin are present in quantities that greatly exceed the recommended daily intake, lending to their high risk for harmful accumulation and toxicity.”

Niacin is found in many energy drinks, and when taken in safe quantities, it can help improve cholesterol levels, lower cardiovascular risk, maintain skin health, treat headaches, and even improve liver function. But when taken in excess, it can cause nausea, stomach upset, muscle breakdown, and abnormal liver tests. Vitamin B3 can also be found naturally in food items such as yeast, meat, fish, milk, eggs, nuts, green vegetables, and beans. Vitamin B3 deficiency is rare in developed countries, leading doctors to advise against self-medicating with niacin.


Note: We changed the wording in the headline from “contract” to “develop” to better distinguish between hepatitis that’s transmissible and the kind that can result from various causes, including toxins, drugs, alcohol, various nutrient overdoses, viruses, and ischemia.

[BMJ Case Reports]