So many folks (like, literally millions) reach for a caffeinated beverage in the morning in order to wake up and feel alert. And many more drink coffees, teas, and energy drinks as the day goes on in order to stay awake. But what are the signs you are sensitive to caffeine?
If you have a caffeine sensitivity, even a small amount of the stuff can make you feel downright bizarre, often leading to symptoms that run the gamut from a pounding heart, to headaches, to feelings of anxiety. "The average person can take in about 200 to 400mg of caffeine and experience no side effects and fall asleep without difficulty at bedtime," Dr. Alexea M. Gaffney-Adams, M.D., a general infectious disease specialist, tells Bustle. "An individual with caffeine sensitivity will experience [some of the symptoms listed below] or caffeine overdose symptoms with ingestion of as little as 100mg of caffeine."
So, what causes it? "There are several reasons it could happen," says Ginger Hultin, MS, RDN, a Seattle-based registered dietitian and nutritionist. "One is the way that caffeine affects the brain. There are several gene variants that affect the way the liver metabolizes caffeine, which may impact how people respond to [it] ... There are also genes that increase the predisposition for high blood pressure when caffeine is regularly consumed, and about 9% of that population has that."
If you've got a caffeine intolerance, you'll know. After consuming it, and for hours afterward, you might notice a few (or all) of the symptoms below. If you do, and they're bothering you, it may be time to get through your day without coffee, and talk to your doctor about a possible sensitivity to caffeine.
So if that's the case, you might want to decrease your caffeine intake, to see if that helps. While most people don't experience unpleasant side effects after drinking coffee, these symptoms might indicate that you're sensitive to caffeine, and need to cut back.
Boekema, P. (1999). Coffee and gastrointestinal function: facts and fiction. A review. Scand J Gastroenterol Suppl. https://pubmed.ncbi.nlm.nih.gov/10499460/
De Giuseppe, R. (2019). Caffeine and blood pressure: a critical review perspective. Nutr Res Rev. https://pubmed.ncbi.nlm.nih.gov/30947761/
Kim, T-W. (2011). Caffeine increases sweating sensitivity via changes in sudomotor activity during physical loading. J Med Food. https://pubmed.ncbi.nlm.nih.gov/21883004/
Lovallo, W. (2005). Caffeine Stimulation of Cortisol Secretion Across the Waking Hours in Relation to Caffeine Intake Levels. Psychosom Med. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2257922/
Lutz, E.G. (1978). Restless legs, anxiety and caffeinism. J Clin Psychiatry. https://pubmed.ncbi.nlm.nih.gov/690085/
Molema, M. (2007). Caffeine and Muscle Cramps: A Stimulating Connection. The American Journal of Medicine. https://doi.org/10.1016/j.amjmed.2006.07.035
Papakonstantinou, E. (2016). Acute effects of coffee consumption on self-reported gastrointestinal symptoms, blood pressure and stress indices in healthy individuals. Nutrition Journal. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4791892/
Planning Committee for a Workshop on Potential Health Hazards Associated with Consumption of Caffeine in Food and Dietary Supplements; Food and Nutrition Board; Board on Health Sciences Policy; Institute of Medicine. Caffeine in Food and Dietary Supplements: Examining Safety: Workshop Summary. Washington (DC): National Academies Press (US); 2014 Apr 23. 5, Caffeine Effects on the Cardiovascular System. Available from: https://www.ncbi.nlm.nih.gov/books/NBK202224/
Richards, G. (2015). Caffeine consumption and self-assessed stress, anxiety, and depression in secondary school children. Journal of Psychopharmacology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4668773/
Dr. Alexea M. Gaffney-Adams, M.D., a general infectious disease specialist
Ginger Hultin, MS, RDN, a Seattle-based registered dietitian and nutritionist
Maranda Elkin, health coach