Can caffeine energy drinks really boost your metabolism?

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.