Doc: Doctor disputes coffee advice

Keith Roach
To Your Health

Dear Dr. Roach: In your recent article on coffee and hydration, I was surprised at your reply. As a retired M.D. for almost 20 years, I recall teaching my patients that coffee with caffeine should not be included in total daily intake, since it is a diuretic and takes more out of the body than it puts in — a negative balance. Google seems to back that up.

Also, isn’t there an increase in kidney stones with coffee?

Should you revisit this, distinguishing between caffeine-containing and noncaffeine coffee?

Your answer seemed so simplistic. Or am I missing something?

R.B., M.D.

Dear R.B.: I also was taught that caffeine is a diuretic, but the medical literature shows that although large doses of caffeine in people who never drink it causes an increase in urine output, within a few days, this effect is lost.

According to a 2003 review, “In individuals who regularly consume tea or coffee … doses of caffeine equivalent to the amount normally found in standard servings of tea, coffee and carbonated soft drinks appear to have no diuretic action.”

As far as kidney stones go, coffee has been found, in one large study, to have no effect on kidney stone development, and in another to decrease the rate of stone formation by about 10 percent. That difference was identical for caffeinated versus decaffeinated.

I am in the distinct minority of physicians who don’t regularly drink coffee, so I have no personal interest in wanting to minimize any possible bad health effects of coffee. The fact is that most data now shows that coffee is safe and has few ill effects.

Dr. Roach Writes: I received many responses to my recent column on the pain associated with breast biopsies, the vast majority of which were from women who had had good experiences during their breast biopsies and wanted to encourage other women in their situation to not be afraid and to proceed with the procedure.

However, I also heard from women who noted that with a chronic pain syndrome, such as fibromyalgia, the breast biopsy can indeed be very painful, and recommended that women who have similar issues discuss other types of pain management before the biopsy is performed.

One woman suggested I have a large needle placed in the scrotum to see if it caused me more than “discomfort.” That wasn’t very nice.

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