A large international study has found that coffee and energy drinks have sharply contrasting effects on suicide risk.
The research, published on 2 June 2025 as the first systematic review and meta-analysis on this subject, pooled data from 17 studies across countries, including the United States, Korea, Germany, Finland, Turkey, Canada, and Nigeria, covering 1.57 million participants aged 15 to 48.
The analysis showed that people who consumed more than 60 cups of coffee per month, roughly two cups per day, had a 28% lower risk of suicide attempts compared to non-drinkers.
In contrast, those who consumed energy drinks as little as once a month were found to have a significantly higher risk of both suicidal thoughts and suicide attempts, with the risk rising steeply as consumption increased.
At 21 to 30 cans per month, the odds of attempting suicide were almost three times higher than those who did not consume energy drinks.
“The results are quite striking: suicide attempts were 30% lower among coffee drinkers compared with energy drink consumers,” said Dr. Guillaume Davido, a psychiatrist specializing in addiction studies at Bichat-Claude Bernard Hospital in Paris, in an interview with Medscape France.
The study, registered under PROSPERO (CRD42024595935), followed PRISMA guidelines for systematic reviews. It identified differences not only in the beverages themselves but also in the types of people who consume them. Coffee drinkers tended to be older, while energy drink users were predominantly young men, a group already at higher risk of suicide.
Researchers suggested several explanations for the difference. Coffee contains primarily caffeine, which may have mood-stabilizing and neuroprotective effects. Energy drinks, however, often include other stimulants such as taurine, guarana, and ginseng, alongside high amounts of sugar. These additional ingredients are suspected of contributing to anxiety, agitation, and mood swings.
Dr. Davido noted that energy drink use is often associated with other risky behaviors, including alcohol and drug consumption. “In consultations, use of energy drinks should be seen as a red flag,” he said. “It may indicate other issues, such as substance use or underlying psychiatric vulnerabilities.”
The review also found that male gender and substance use were strongly linked to higher caffeine intake. All five studies that looked at alcohol and cigarette use found a clear overlap with heavy caffeine or energy drink consumption.
Despite the scale of the analysis, the authors cautioned that the overall certainty of the evidence was rated low, due to the limitations of the included studies and differences in how caffeine amounts were measured. They also stressed that the associations may reflect broader lifestyle factors rather than direct causation.
Still, the findings raise important public health questions. The World Health Organization (WHO) estimates that nearly 700,000 people die by suicide each year, with many millions more attempting it. Given that energy drinks are most popular among adolescents and young adults, the researchers argue that greater awareness and screening for energy drink consumption could help identify individuals at risk.
“We thought it was mainly the caffeine in energy drinks that posed a problem,” Dr. Davido said. “Yet this study concludes that coffee, also high in caffeine, does not increase suicide risk, and may even reduce it. That is almost a revelation.”
The authors call for further studies to better understand the biological and social factors behind the contrasting effects. In the meantime, they recommend that clinicians routinely ask patients about their energy drink intake, especially in mental health or sleep-related consultations.