Celsius energy drink: Unveiling its functional benefits amidst concerns about caffeine risks

By Claire Wolters | Fact-checked by Jessica Wrubel
Published December 4, 2023

Key Takeaways

  • Popular energy drink Celsius is studied to boost metabolism and help burn fat.

  • Just don’t drink too many, or you’ll be at risk for caffeine overload.

Celsius energy drinks continue to rise in popularity. The company’s shares surged 4000% over the last five years, and sales have increased, too. Marketed as a functional beverage, Celsius’ growth may be in part attributed to its health claims—and advertising department—which say the beverage is fat-burning and metabolism-boosting.[]

However, the drink is high in caffeine, an ingredient that doctors have scrutinized as being unsafe for children—and which has prompted lawsuits for other energy-drink sellers. 

Catherine Rall, RD, a dietitian with women’s wellness company HappyV, says, “Celsius is a drink that exploded in popularity before people realized the health risks involved,” most poignant for people sensitive to caffeine.

“Individuals with sensitivities to caffeine or artificial sweeteners should exercise caution when consuming Celsius,” says Trista Best, MPH, RD, LD, a registered dietitian with Balance One Supplements. She adds that “as with any energy drink, moderation is key.”

Overall, dietitians encourage contextualizing the risks and benefits of energy drinks—and drinking them sparingly.

A healthy beverage?

Destini Moody, RD, CSSD, LD, a sports dietitian and founder of nutrition resource and counseling service The Athlete’s Dietitian, says there “actually is some promising evidence that Celsius can boost your metabolism indirectly, at least if you’re a sedentary adult.”

One study that assessed Celsius use among previously sedentary males found that when participants that drank Celsius along with exercise, they had “significantly greater decreases in fat mass and percentage body fat” and increases in VO2peak” than participants who did not drink Celsius. These benefits were not noticed in participants who drank Celsius but did not exercise.[] 

Having health claims rooted in research is always a good sign. But Moody says it’s important to look at studies in context to understand their benefits and limitations. For example, researchers have found that taking 100 mg of caffeine (half the amount as in Celsius) can increase your resting metabolic rate by up to 4%. As a daily value, this translated to an extra 150 calories burned for participants described as lean and an extra 79 calories for participants described as obese.[]

Put in context, Moody says burning off an extra 79 calories might cancel out an Oreo cookie but is “not nearly enough to actually help weight loss in a meaningful way.”

Still, Celsius’ lack of sugar and artificial preservatives can not be ignored as a benefit especially for people who are looking to cut back on their sugar intake and daily calories. A can contains about 10 calories.

Best says that Celcius’ use of natural ingredients like green tea extract, ginger, and guarana (which contains caffeine) and omittance of artificial preservatives “may appeal to health-conscious consumers.” 

Celsius is not void of artificial ingredients altogether, as it contains sucralose, commonly sold as Splenda. Sucralose is an FDA-approved artificial sweetener that, on its own, contains zero calories and is 600 times sweeter than table sugar. While it is generally considered safe, more research is needed on its long-term health impact.[]

Energy drink risks

Not exclusive to Celsius, energy drinks contain high amounts of caffeine which can come with health risks.

Excess caffeine can cause increased heart rate and blood pressure levels, which can be dangerous for anyone, but particularly children or people with heart conditions. It can also cause gastrointestinal distress and diarrhea in some people, which can contribute to dehydration as well as impact sleep quality.

The FDA does not recommend a limit for caffeine intake but says that consuming up to 400 mg a day is generally safe for adults. Celsius drinks contain about 200 mg of caffeine, though exact levels can vary per flavor.

To stay on the safe side, talk to patients about following label limits of drinking no more than two cans per day—or fewer if they are getting caffeine from other sources.

“Caffeine can sneak into your system in ways that you don’t calculate,” Moody says. “If you have your coffee in the morning, a Celsius before your workout, and some black or green tea in the evening, you could find yourself with dangerous levels of caffeine in your system, which can be harmful for your heart and cause other side effects like headaches and feelings of anxiety.”

Side effects aside, college athletes, in particular, may want to be mindful of overconsuming energy drinks due to caffeine limits set by the NCAA. The NCAA does not ban energy drinks but sets limits on caffeine levels in drug testing. According to Celsius, people who follow company recommendations for consumption will not violate NCAA regulations.

Dan Gallagher, a registered dietitian at Aegle Nutrition, stresses that, like most foods and beverages, Celsius is healthy in moderation.

“The issue with energy drinks, like Celsius, comes when people over consume them,” Gallagher says. “Overconsumption can cause health issues. When used in moderation, caffeine can help energize you, which can lead to harder workouts, leading to more fat burn. Overconsumption is the issue, not the energy drink itself.”

What this means for you

Celsius energy drinks may help users burn calories while working out. However, drinking more than the recommended limit is risky due to excess caffeine.

Share with emailShare to FacebookShare to LinkedInShare to Twitter