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Caffeine: Is it dehydrating or not?By Mayo Clinic staff
Original Article: http://www.mayoclinic.com/health/caffeinated-drinks/AN01661
- With Mayo Clinic nutritionist
Katherine Zeratsky, R.D., L.D.read biographyclose window
Katherine Zeratsky, R.D., L.D.Katherine Zeratsky, R.D., L.D.
As a specialty editor for the nutrition and healthy eating guide, Katherine Zeratsky helps you sort through the facts and figures, the fads and the hype to learn more about nutrition and diet.
A Marinette, Wis., native, Katherine is certified in dietetics by the state of Minnesota and the American Dietetic Association. She has been with Mayo Clinic since 1999.
She is active in nutrition-related curriculum and course development in wellness nutrition at Mayo Clinic in Rochester, Minn., and nutrition education related to weight management and practical applications of nutrition-related lifestyle changes.
Other areas of interest include food and nutrition for all life stages, active lifestyles and the culinary arts.
She graduated from the University of Wisconsin-Madison, served a dietetic internship at the University of Iowa Hospitals and Clinics, and worked as a registered dietitian and health risk counselor at ThedaCare of Appleton, Wis., before joining the Mayo Clinic staff.
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Caffeine: Is it dehydrating or not?
I've been seeing ads that say caffeinated drinks hydrate you as well as water does. Is this true?
from Katherine Zeratsky, R.D., L.D.
It is true that caffeinated fluids can contribute to your daily fluid requirement.
Drinking caffeine-containing beverages as part of a normal lifestyle doesn't cause fluid loss in excess of the volume ingested. While caffeinated drinks may have a mild diuretic effect — meaning that they may cause the need to urinate — they don't appear to increase the risk of dehydration.
Still, caffeinated drinks can cause headaches and insomnia in some people. Water is probably your best bet to stay hydrated. It's calorie-free, caffeine-free, inexpensive and readily available.Next question
Olive oil: What are the health benefits?
- Armstrong LE, et al. Caffeine, fluid-electrolyte balance, temperature regulation, and exercise-heat tolerance. Exercise and Sport Sciences Review. 2007;35:135.
- Maughan RJ, et al. Caffeine ingestion and fluid balance: A review. Journal of Human Nutrition and Dietetics. 2003;16:411.
- Lopez RM, et al. The influence of nutritional ergogenic aids on exercise heat tolerance and hydration status. Current Sports Medicine Reports. 2009;8:192.
- Ruxton CH, et al. Black tea is not significantly different from water in the maintenance of normal hydration in human subjects: Results from a randomized controlled trial. British Journal of Nutrition. 2011;106:588.
- Heneghan C, et al. Mythbusting sports and exercise products. BMJ. 2012;345:e4848.
- Caffeine. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Aug. 13, 2013.
- Zeratsky KA (expert opinion). Mayo Clinic, Rochester, Minn. Aug. 13, 2013.