So long as they stay under 550 milligrams, drinks containing caffeine are like water and contribute to the body’s daily hydration needs.
As far as the specific interaction between coffee and the kidneys is concerned, an observational study published last year of more than 8,000 Koreans found that those who consumed more than two cups of coffee a day had a lower risk of kidney disease than nondrinkers.
Similarly, coffee seems to be protective against kidney stones. (Another caffeinated drink, tea, also appears to guard against stones, though sodas — both caffeinated and not — increase the risk of stone formation.)
While nary a month goes by without some new research study about coffee and caffeine, there’s scant evidence that normal consumption poses any health risks. Neither seems to increase the chance of cancer or heart attacks, and regular coffee drinkers appear to have a lower rate of cardiovascular disease.
As with so many things, so long as you enjoy coffee and other caffeinated beverages in moderation, drink up!
Prescott, a physician and medical researcher, is president of the Oklahoma Medical Research Foundation. Cohen is a marathoner and OMRF’s senior vice president and general counsel.