Author: Brooke Carmen, PT, DPT: Doctor of Physical Therapy and Blog Contributor. Loves fun informational gems. Fitness addict and wannabe foodie. Emphasizes patient-specific treatment style and promotes goal-oriented care. Learn more about Brooke on here. gems. Fitness addict and wannabe foodie. Emphasizes patient-specific treatment style and promotes goal-oriented care. Learn more about Brooke on here.
You may have heard about the teenage boy in South Carolina that passed away from what is believed to be a caffeine overdose in May, 2017.
The 16-year-old-boy drank a large mountain dew, a latte, and a large energy drink the day of his death which ultimately lead to cardiac arrhythmia.
So, how much caffeine is too much?
Caffeinism is the term for a caffeine overdose and it usually occurs around 1-1.5 g caffeine ingested in one day.  This is about 10-15 eight ounce cups of coffee. .
Caffeine clearly can have negative side effects such as death. Other side effects include the well-known jitteriness, insomnia, and anxiety. In toxic stages, it can cause rhabdomolysis which is the breakdown of skeletal muscle. It can also trigger manic states.
Not all levels are caffeine are necessarily "bad."
Caffeine is shown to help with sport performance, particularly with aerobic activity such as long distance runners. The level of how much caffeine is good before aerobic activity is unclear and ranges from 3-6 mg. Those who do not regularly take caffeine, but do prior to aerobic activity may have more benefit effects. 
When think of how to ingest caffeine, coffee comes to mind and indeed, the coffee bean has a good source. Tea and chocolate are other substance that contain caffeine.
Certain medications, such as Advil and Motrin also contain caffeine.
Your physical therapist cannot recommend or prescribe supplements such as caffeine. If you are looking to change your caffeine intake, talk to your primary doctor first.
It’s important to know how caffeine interacts physically and physiologically within your body. Medications and activities are different for everyone, making the effects of caffeine different for everyone as well.
When you attend physical therapy, we do take caffeine intake levels into consideration as the physical activities we prescribe are effected by that.
1. “Caffeine.” Wikipedia, Wikimedia Foundation, 18 Aug. 2017, en.wikipedia.org/wiki/Caffeine#Physical_2.
2. Bell, Douglas G., and Tom M. McLellan. “Exercise Endurance 1, 3, and 6 h after Caffeine Ingestion in Caffeine Users and Nonusers.” Journal of Applied Physiology, American Physiological Society, 1 Oct. 2002, jap.physiology.org/content/93/4/1227.