Could My Teen's Workout Supplements Be Causing Mood Changes?
Your son has been more irritable lately. Shorter fuse. Harder to talk to. You've chalked it up to stress, school, the usual. But if the timeline overlaps with a new supplement, it may be worth a closer look at what's actually in it.
This post focuses specifically on the mood and behavior angle. For a fuller breakdown of protein needs, creatine, and other topics, see our longer guide.
Caffeine Is Ubiquitous. That Doesn't Make It Harmless.
Most sports pre-workouts and energy drinks used by teen athletes contain far more caffeine than parents realize. A standard cup of coffee has roughly 80 to 100 mg. Many pre-workout products contain 200 to 400 mg per serving. The American Academy of Pediatrics recommends adolescents consume no more than 100 mg per day.
Published research links high caffeine intake in adolescents to increased irritability, decreased self-control, and a meaningful increase in aggressive behavior over time. A significant part of this is mediated by sleep. Caffeine taken before afternoon or evening practice delays sleep onset and disrupts sleep architecture, and the connection between poor sleep and emotional dysregulation in teenage boys is well established. A teen who is chronically under-slept and taking daily stimulants is starting every day from a compromised baseline.
Energy drinks like Celsius, Alani Nu, and Prime Energy carry the same concern. Because they are sold as beverages rather than supplements, they tend to feel less like something that needs scrutiny. The stimulant load is the same
What Else Is in the Product
L-tyrosine is a common pre-workout ingredient marketed for focus and anti-fatigue effects. It is the direct precursor to dopamine and norepinephrine, the brain chemicals that drive motivation, stress response, and arousal. When these accumulate faster than the brain can clear them, the result is not simply more energy. In some boys it shows up as irritability, a shorter fuse, difficulty de-escalating from frustration, or aggression that feels out of proportion to the situation. A meaningful portion of the population carries genetic variants that slow the clearance of these brain chemicals, and for those boys, repeated daily dosing can push reactivity well above their normal baseline.
Methylated B vitamins appear on labels as methylfolate, 5-MTHF, methyl-B12, or methylcobalamin, and show up in pre-workouts, nootropic blends, and general energy products. For most people they are fine. For individuals with certain genetic variants, high-dose methylated nutrients can push the nervous system into overdrive, producing anxiety, panic, irritability, or in some cases significant rage. If your teen is taking anything with "methyl" in the ingredient name and has developed unexplained mood changes, the supplement is worth a closer look.
Yohimbine (pronounced yo-HIM-been) shows up in pre-workouts and fat burners, often tucked into proprietary blends where the dose is not disclosed. It acts on the sympathetic nervous system and has been associated with anxiety, irritability, elevated heart rate, and in some cases manic episodes. It is not appropriate for teenagers under any circumstances. What makes yohimbine particularly important to flag is that it has documented interactions with a number of commonly prescribed psychiatric medications, including SNRIs like venlafaxine (Effexor), tricyclic antidepressants, and MAOIs. If your teen is on any medication for depression, anxiety, or ADHD, yohimbine on a supplement label is a specific reason to check with their prescriber before they use the product.
DHEA (dehydroepiandrosterone) is a hormone precursor to testosterone, legal to sell as a supplement in the US despite being banned by most sports organizations. Testosterone-support products containing DHEA are widely marketed to teen boys on social media. Elevated androgen activity has been associated with mood volatility and a lowered threshold for reactive aggression. DHEA has also been documented to trigger manic symptoms in some individuals, with concurrent antidepressant use listed as a risk factor in published case reports and by the Mayo Clinic.
What to Watch For
Symptoms that could surface when a new supplement enters the picture include a shorter fuse or increased irritability that is out of character, difficulty de-escalating from frustration or conflict, sleep changes including trouble falling or staying asleep, and physical symptoms like elevated heart rate, shakiness, or headaches.
If the timeline correlates with a new product or a change in dose, that connection is worth exploring. If you suspect a supplement may be contributing to mood or behavior changes, pausing it for 10 to 14 days can be informative. If symptoms improve during that window, you have useful information. Knowing what is in the stack gives you something specific to point to, which makes the conversation easier for everyone.
For more on sports nutrition for teens: What's in the Stack? A Parent's Guide to Teen Sports Supplements and Fueling the Teen Athlete
© 2026 Ellie Whitenack, MS, Integrative Nutrition, LLC. All rights reserved.
This content is for educational purposes only and is not intended to diagnose, treat, or replace medical care.
Bella, Y. F., Cupido, S. R. S., Inacio, P. A. Q., Sobral, M. L. P., & Vieira, R. P. (2025). Pre-Workout Supplements and Their Effects on Cardiovascular Health: An Integrative Review. Journal of cardiovascular development and disease, 12(4), 112. https://doi.org/10.3390/jcdd12040112
Healthy Eating Research. Healthy Beverage Consumption Guidelines for Children and Adolescents. Consensus Statement. January 2025. healthyeatingresearch.org
Hecht, C., Bank, N., Cook, B., & Mistovich, R. J. (2024). Nutritional Recommendations for the Young Athlete. Journal of the Pediatric Orthopaedic Society of North America, 5(1), 599. https://doi.org/10.55275/JPOSNA-2023-599
Kristjansson, A. L., Kogan, S. M., James, J. E., & Sigfusdottir, I. D. (2021). Adolescent caffeine consumption and aggressive behavior: A longitudinal assessment. Substance abuse, 42(4), 450–453. https://doi.org/10.1080/08897077.2021.1876810
Longobardi, I., Solis, M. Y., Roschel, H., & Gualano, B. (2025). A short review of the most common safety concerns regarding creatine ingestion. Frontiers in nutrition, 12, 1682746. https://doi.org/10.3389/fnut.2025.1682746
Ostojic, S. M., Calleja, J., & Jourkesh, M. (2010). Effects of short-term dehydroepiandrosterone supplementation on body composition in young athletes. The Chinese journal of physiology, 53(1), 19–25. https://doi.org/10.4077/cjp.2010.amh090
