So how much coffee can you drink every day?

How much coffee can you drink every day?

SUMMARY: We now know that coffee may not be as dehydrating as you may have believed. But this does NOT mean you can drink unlimited amounts. The key is to ensure that your total caffeine intake stayed BELOW 300mg daily and adjust your drinking schedule to non-fasting hours.


In 2016, The American Journal of Clinical Nutrition conducted a study3 called the Beverage Hydration Index. In this study, it was found that the dehydrating effects of caffeine may only occur when the dose of caffeine exceeds 300mg per day: 

An acute dose of 250–300 mg caffeine is unlikely to have a measurable effect on urine output, although such an effect is likely to be seen when the dose exceeds 300 mg. In line with these observations, we did not observe an impact from moderate caffeine intake (96–212 mg) on net fluid balance in the present study.

The Mayoclinic (4) states that an excessive amount of caffeine is more than 500 to 600 mg a day, or the equivalent of between four and seven cups of coffee daily.

Researcher Dr. Armstrong argues that moderate caffeine intake below 500mg will not increase urination or dehydration (7): 

“There is no evidence to suggest that moderate caffeine intake (less than 456 mg) induces chronic dehydration or negatively affects exercise performance, temperature regulation, and a circulatory strain in the hot environment. 

This argument isn’t new. Another study from as early as 1987 asserted that only doses of 360 mg of caffeine or greater produced significantly more urine volume7.

So what does all this mean?

The research indicates that a moderate amount of caffeine intake does NOT increase dehydration via increased urine production. However, research findings differ as to HOW MUCH caffeine constitutes a “moderate” amount of daily caffeine intake! 

If you’re concerned about dehydration but are a regular coffee drinker, stay on the safe side and limit yourself to 300mg of caffeine per day to keep your coffee cravings at bay in Ramadan while still enjoying your daily caffeine fix safely.

Take home point: Keep your caffeine intake UNDER a safe 300mg per day to avoid the diuretic effects of excessive caffeine consumption!

Tip: Limit coffee to 300mg of caffeine per day in Ramadan

To help you follow this daily guideline, the Mayoclinic4 provides a chart with caffeine doses found in cups of common beverages listed below. Keep in mind that caffeine content in your favourite beverages may differ. “The actual caffeine content of a cup of coffee or tea can vary considerably because of factors such as origin, processing and preparation method, including brewing time”, so these guidelines can help you estimate your caffeine intake. How much do you currently drink in comparison? 

Note: 1 cup = 8 ounces. 

All values listed on this chart, except for Espresso, are for a 1-cup serving.

Table listing the size and associated amount of caffeine with common hot drinks such as coffee, latte and teas. Generally, coffee has more caffeine than tea.Chart from Mayoclinic.com4

Notice that 1-2 cups of coffee is well under the guideline of 300mg a day and can be maintained during Ramadan.

If you currently exceed 300mg of caffeine per day, Dietitian YaQutullah Ibrahim recommends you adjust your coffee intake gradually BEFORE Ramadan to avoid feeling the unpleasant effects of sudden abstention of caffeine.

You can gently reduce your caffeine by adding decaffeinated coffee mixed into your regular coffee to reduce the total amount of daily caffeine without dramatically changing your coffee habit.

Enjoy your coffee as part of a holistic healthy Ramadan lifestyle! Luckily, we’ve got you covered!

The Ramadan Reset eBook is your complete solution to healthy eating, exercise, sleep, coffee and so much more in Ramadan! With 90 dietitian-created recipes, full fasting fitness schedules for ALL levels, your Ramadan will never be the same! Click HERE to learn more!


  1. Eddy, N. B., & Downs, A. W. (1928). Tolerance and cross-tolerance in the human subject to the diuretic effect of caffeine, theobromine and theophylline. Journal of Pharmacology and Experimental Therapeutics, 33(2), 167-174.
  2. Armstrong, L. E., Pumerantz, A. C., Roti, M. W., Judelson, D. A., Watson, G., Dias, J. C., … & Kellogg, M. (2005). Fluid, electrolyte, and renal indices of hydration during 11 days of controlled caffeine consumption. International journal of sport nutrition and exercise metabolism, 15(3), 252-265.
  3. Maughan, R. J., Watson, P., Cordery, P. A., Walsh, N. P., Oliver, S. J., Dolci, A., … & Galloway, S. D. (2016). A randomized trial to assess the potential of different beverages to affect hydration status: development of a beverage hydration index. The American journal of clinical nutrition, 103(3), 717-723.
  4. Mayo Clinic Staff. (2017, April 14). Caffeine content for coffee, tea, soda and more. Retrieved from
  5. Armstrong LE, Casa DJ, Maresh CM, Gaino MS. Caffeine, fluid-electrolyte balance, temperature regulation, and exercise-heat tolerance. Exerc Sport Sci Rev, 2007;35(3):135-40.
  6. Killer, S. C., Blannin, A. K., & Jeukendrup, A. E. (2014). No evidence of dehydration with moderate daily coffee intake: a counterbalanced cross-over study in a free-living population. PloS one, 9(1), e84154.
  7. Passmore, A. P., Kondowe, G. B., & Johnston, G. D. (1987). Renal and cardiovascular effects of caffeine: a dose–response study. Clinical science, 72(6), 749-756.
  8. Lindmier C. (2015, March 4). WHO calls on countries to reduce sugars intake among adults and children. Retrieved from


Does coffee dehydrate you in Ramadan?
No Comments

Post A Comment