Can energy drinks really boost your metabolism? Here’s what the science says.

Energy drinks have taken on a new role. Now, in the hands of gym-goers and fitness influencers, they are being used not just to help you stay up but also to slim down.

While many energy drinks pack a lot of sugar (and thus calories), low-calorie options have flourished. Some brands suggest that choosing their low-calorie drink over a sugary option can aid in weight management.

Others go further, claiming the drinks help boost metabolism and enhance fat burning. But can energy drinks really help you shed pounds? Here’s what some experts say.

Drink up to slim down?

“Any kind of caffeinated drink will increase metabolism in the short term,” says Andrew Jagim, a sports medicine specialist at the Mayo Clinic and one of the authors of the International Society of Sports Nutrition’s position on energy drinks. The problem is that a daily intake of 100mg of caffeine is estimated to burn 100 calories a day. “It’s probably not going to be enough to really move the needle in terms of substantial fat loss over time,” says Jagim.

Jeffrey Stout, an exercise physiologist at the University of Central Florida who has conducted studies for an energy drink brand, adds, “energy drinks seem to have limited effect as a weight loss aid when used alone but appear to be more effective when combined with exercise.”

So, while there is support for these companies to say their drinks boost metabolism, the results are far from dramatic, says Lena Bakovic, a registered dietitian with Top Nutrition Coaching. “There is no correlation between energy drink consumption and weight loss at this time,” she says.

​(Losing weight leads to better health? Not necessarily.)

For most energy drinks, caffeine is the main active ingredient, often mixed with taurine, glucuronolactone, guarana, and B vitamins, to create what manufacturers call an “energy blend.” However, some of the long-term safety and effectiveness of some of the ingredients in energy drinks haven’t been thoroughly studied, especially in combination. “Because energy drinks are not regulated by the FDA, the actual quantity of ingredients listed on the label may also be inaccurate,” says Bakovic.

In some cases, the caffeine in energy drinks is derived from guarana, a plant native to the Amazon that contains more caffeine than coffee, tea, and yerba mate. Another common ingredient is epigallocatechin gallate (EGCG), a compound from green tea that may boost metabolism and fat oxidation. Taurine, an amino acid naturally present in meat, fish, and eggs, is believed to enhance exercise performance. Some energy drinks also include chromium, which one study suggests helps control hunger, but results from other studies are mixed.

Additionally, some of these low-calorie energy drinks contain low-calorie or calorie-free sweeteners, such as erythritol, sucralose, and stevia. While generally considered safe, the taste can be off-putting, and erythritol may cause digestive issues in some people.

(Low-calorie sweeteners might not be as good for us as we thought.)

Jagim notes that other common ingredients like electrolytes and B vitamins pose neither a high risk nor a significant reward. B vitamins, for example, are found in meat, dairy, leafy greens, and beans and have many roles, including in energy production. Supplementing them may help if you’re deficient (as can be the case for vegans and vegetarians), but if you get enough, you’ll just pee out the excess, says Jagim.

Sip with caution

Although short-term use appears safe for healthy adults, the long-term effects of energy drinks are still under study. Jagim says that anyone who consumes a lot of caffeine—a morning coffee, a pre-workout energy drink, and an afternoon pick-me-up—is bombarding their system with stimulants. “Your stress levels are going to be elevated throughout the day and we know that can have detrimental effects long term,” he says.

(Do you have chronic stress? Look for these signs.)

The FDA advises adults to keep their caffeine intake under 400 milligrams daily. To put that in perspective, a 12-ounce can of caffeinated soda usually has 30 to 40 milligrams of caffeine, an 8-ounce cup of tea contains 30 to 50 milligrams, and an 8-ounce cup of coffee has about 80 to 100 milligrams. Energy drinks, however, can pack anywhere from 40 to 250 milligrams of caffeine per 8-ounce serving.

(You actually can consume too much caffeine. Here are the risks.

Bakovic and Jagim advise against using energy drinks daily because it could lead to dependence. “The negative health effects would definitely outweigh the slight benefit you get from the metabolic standpoint,” says Jagim.

Stout agrees energy drinks shouldn’t be relied on as a weight loss strategy. “Focus on a balanced diet, regular exercise, proper sleep, and staying hydrated primarily with water,” he says.