Updated: May 12, 2025
What do you know about stimulants like energy drinks, coffee, and more? In this series, we cover stimulant ingredients and the safety of stimulants.
Top Takeaways:
- Stimulants are found in coffee, tea, energy drinks, and supplements, and their effects vary by type, dose, and your sensitivity.
- Combining or mixing stimulant ingredients can intensify side effects and can lead to adverse health outcomes for some.
- The FDA regulates many stimulants, but companies must ensure safety.
What are stimulants?
Stimulants are a broad class of compounds that can boost mood, improve focus, increase physical and mental energy, and enhance sociability. Some even have ergogenic effects, meaning they can enhance physical performance.
We encounter stimulants in many forms, including prescribed medications, dietary supplements, beverages, and everyday foods.
Where do I find stimulant ingredients? What are common stimulant ingredients?
We can find stimulant ingredients in a variety of common foods, beverages, and supplements.
Common stimulant ingredients include:
- B-complex vitamins
- Caffeine
- Carnitine
- Ginseng
- Guarana
- Taurine
We find many of these ingredients in coffee, teas, energy drinks, soda pops, drink flavor enhancers, chocolate, and dietary supplements.
Foods that naturally contain stimulant ingredients:
- Chocolate: Contains caffeine and theobromine, both mild stimulants
- Tea (green, black, oolong): Naturally contains caffeine and L-theanine
- Coffee: A primary natural source of caffeine
- Yerba mate: Contains caffeine and other xanthines (theobromine, theophylline)
- Guarana seeds: Found in some energy products; naturally high in caffeine
Beverages with added or naturally occurring stimulant ingredients
- Energy drinks: Often contain caffeine, taurine, guarana, B-vitamins, ginseng
- Pre-workout drinks/powders: Caffeine, carnitine, beta-alanine, and more
- Soda/pop: Often contains added caffeine
- Coffee and espresso drinks: Naturally high in caffeine
- Matcha and specialty teas: Caffeine and theanine combination
Dietary supplements
- Caffeine pills: concentrated caffeine
- “Fat-burning” supplements: Often include caffeine, guarana, green tea extract
- Focus and memory supplements: May contain ginseng, B-vitamins, or nootropic blends
- Multivitamins and B-complex vitamins: May be included in energy support formulas
How do stimulant ingredients work?
Stimulants primarily work by affecting neurotransmitter chemicals that carry signals in the brain. For example:
- Caffeine blocks adenosine, a compound that makes you feel sleepy.
- Guarana contains natural caffeine but releases it more slowly.
- B-complex vitamins help with energy metabolism but aren’t stimulants in the strictest sense.
Our body’s response depends on:
- The type of stimulant
- The dose and dose rate
- Our age, sex, weight, health, sensitivity, and more
Can stimulant ingredients harm my health?
When used as directed and intended, stimulant ingredients are unlikely to harm someone’s health.
However, energy drinks and supplements often contain a mix of stimulant ingredients. Stimulants like caffeine, guarana, high-dose B-vitamins, and more can raise heart rate, increase blood pressure, and in some cases, trigger irregular heart rhythms or anxiety. When multiple stimulants are combined in a single product, their effects can compound, increasing the risk of adverse health outcomes.
Some people are more sensitive to stimulants, especially those with heart conditions, anxiety, high blood pressure, or during pregnancy.
Children and teens are also at greater risk, and energy drinks are not recommended for them.
Moreover, overconsumption, whether through several products or supplements, has been linked to emergency room visits and, in rare cases, serious cardiovascular events, even death.
Are stimulants legal? Are they regulated?
Many stimulants, like caffeine, dietary supplements, and prescribed medications, are legal when used as directed.
Other natural and human-made stimulants (e.g., cocaine, methamphetamine, etc.) are illegal, addictive, and can cause grievous bodily harm when produced and consumed.
The U.S. Food and Drug Administration (FDA) regulates and approves stimulant ingredients if they meet the safety criteria of Generally Recognized as Safe (GRAS) ingredients or dietary supplements. Therefore, manufacturers are responsible for ensuring the stimulant ingredients found in foods, beverages, and dietary supplements are pure and safe for consumption when taken and ingested as directed.
Are all stimulants found in foods, beverages & dietary supplements the same?
No, all stimulants are not the same. Our bodies will react in many ways depending on the stimulant exposed to our system. The body’s reaction will vary greatly depending on the exposure route, dose, and dose rate.
Additionally, stimulant ingredients interact with different molecules and receptors in our body. These interactions can determine the way our bodies respond to the stimulant ingredient.
The good news.
Stimulant ingredients have long been part of the human diet and can be safely enjoyed in moderation as part of a balanced, healthy lifestyle.
If you have any questions about ingredients or ideas for a blog post, please send us an email or submit your idea to us at go.msu.edu/cris-idea.
Citations and further reading.
National Research Council (US) Committee on Toxicology. (2007). Toxicity Testing for Assessment of Environmental Agents: Interim Report. National Academies Press (US). https://www.ncbi.nlm.nih.gov/books/NBK223808/
Seifert, S. M., Schaechter, J. L., Hershorin, E.R., & Lipshultz, S. E. (2011). Energy beverages: Content and safety. Mayo Clinic Proceedings, 86(1), 1–6. https://doi.org/10.4065/mcp.2010.0381
Center for Research on Ingredient Safety. Everyday toxicology: The dose makes the poison—and the cure. Center for Research on Ingredient Safety, Michigan State University. https://cris.msu.edu/news/everyday-toxicology/everyday-toxicology-the-dose-makes-the-poison-the-cure/
Center for Research on Ingredient Safety. Everyday toxicology: Dose & dose rate. Center for Research on Ingredient Safety, Michigan State University. https://cris.msu.edu/news/everyday-toxicology/everyday-toxicology-dose-dose-rate/
Nehlig, A., Daval, J.-L., & Debry, G. (1992). Caffeine and the central nervous system: Mechanisms of action, biochemical, metabolic and psycho stimulant effects. Psychopharmacology, 114(1), 1–14.https://doi.org/10.1007/s00213-004-2000-x
Center for Research on Ingredient Safety. Exploring regulations. Center for Research on Ingredient Safety, Michigan State University. https://cris.msu.edu/news/dietary-supplements/exploring-regulations/
Center for Research on Ingredient Safety. What are GRAS ingredients? Center for Research on Ingredient Safety, Michigan State University.https://cris.msu.edu/news/summer-staple-ingredients/what-are-gras-ingredients/.