Evidence explainerTaurineCaffeine (capsules, gum and anhydrous powder)
Is the Taurine in Energy Drinks Bad for You? The Safety Data Points at the Caffeine
Taurine gets blamed for energy-drink jitters. The human safety data on taurine itself are reassuring up to 3 g a day; the stronger stimulant in the can is caffeine.
Key takeaways
- A 2008 risk assessment found strong evidence of no adverse effects from supplemental taurine up to 3 g/day, its observed safe level [1].
- No official upper limit has been set for taurine; higher intakes have been studied less [1].
- Across 25 trials of 0.5 to 6 g/day, taurine caused no significant adverse effects versus control [2].
- In a network meta-analysis of 12 studies, caffeine plus taurine improved anaerobic capacity and reaction time more than either alone [3].
- For the caffeine in the same can, FDA says 400 mg/day is not usually dangerous for healthy adults [4].
The evidence, graded
Pulled from our monograph evidence tables. Grades follow our evidence-grading policy.
- Grade BWorsenedBlood pressure, fasting glucose and triglyceridesTaurine lowered systolic blood pressure by about 4 mmHg, diastolic by about 1.5 mmHg, fasting glucose by about 5.9 mg/dL and triglycerides by about 18 mg/dL versus control; HDL cholesterol did not change. No significant adverse effects versus control.
- Grade CImprovedExercise performance after a single doseTaurine was linked to small-to-moderate improvements in overall performance (g = 0.25), more clearly in males and in endurance, strength/power and agility tasks. No dose-response was seen within 1–6 g. GRADE certainty was low to very low.
What the safety data say about taurine
A 2008 quantitative risk assessment found no systematic pattern of adverse effects from oral taurine in humans, so a standard upper limit could not be derived [1]. Using the observed safe level method instead, it found strong evidence of no adverse effects at supplemental intakes up to 3 g/day [1].
Trials since then point the same way. A 2024 meta-analysis of 25 randomized trials (1,024 participants) using 0.5 to 6 g/day for 5 to 365 days reported no significant adverse effects versus control [2].
What else is in the can
Taurine and caffeine are often co-formulated in energy drinks [3]. A 2025 network meta-analysis of 12 studies found caffeine plus taurine improved anaerobic capacity and reaction time more than either alone, while effects on endurance and heart rate varied [3].
Sleep trouble, restlessness and a fast heart rate are among the caffeine side effects ODS lists [4]. FDA says 400 mg/day of caffeine does not usually have dangerous effects in healthy adults, and the American Academy of Pediatrics says caffeinated energy drinks have no place in children's or teens' diets [4]. See how much caffeine is too much.
What taurine itself does in trials
In the 25-trial analysis, taurine lowered systolic blood pressure by about 4 mmHg, fasting glucose by about 5.9 mg/dL and triglycerides by about 18 mg/dL versus control [2]. Those are modest changes, and they matter for anyone already on medicines that lower blood pressure or glucose, who should check with a clinician first [2].
For exercise, a single 1 to 6 g dose gave small to moderate gains in pooled trials, with low certainty; we cover that in taurine benefits: what trials show [5].
Quick answers
How much taurine is safe per day?
The 2008 risk assessment found strong evidence of safety up to 3 g/day of supplemental taurine [1]. Higher amounts have been studied in less depth [1].
Is taurine a stimulant?
Our sources describe taurine as an amino acid [1]. The ingredient in energy drinks with the stimulant side effects ODS lists is caffeine [4].
Can teenagers have taurine drinks?
Energy drinks also carry caffeine, and the American Academy of Pediatrics says caffeinated energy drinks have no place in children's or adolescents' diets [4].
Keep reading
Full monographs
Related articles
- Taurine Benefits: Small Exercise Gains, Modest Metabolic Shifts, No Memory Boost
- Caffeine Before a Workout: 3 mg/kg, 15 to 60 Minutes Out, and Why It Helps Endurance Most
- How Much Caffeine Is Too Much? 400 mg a Day, 100 mg for Teens, and Why Pure Powder Is Dangerous
- L-Theanine and Caffeine: What the "Calm Focus" Stack Actually Did in Trials
Browse the full Supplement & Nutrient Encyclopedia or all supplement articles.
References
- [1]Risk assessment for the amino acids taurine, L-glutamine and L-arginine. Regul Toxicol Pharmacol, 2008.
- [2]Taurine reduces the risk for metabolic syndrome: a systematic review and meta-analysis of randomized controlled trials. Nutr Diabetes, 2024.
- [3]Caffeine and taurine: a systematic review and network meta-analysis of their individual and combined effects on physical capacity, cognitive function, and physiological markers. J Int Soc Sports Nutr, 2025.
- [4]Dietary Supplements for Exercise and Athletic Performance: Fact Sheet for Health Professionals. NIH Office of Dietary Supplements, 2024.
- [5]Does One Shot Work? The Acute Impact of a Single Taurine Dose on Exercise Performance: A Meta-Analytic Review. Scand J Med Sci Sports, 2025.