Are prunes better for constipation?

Dear Dr. Roach: A while back, you wrote about an 82-year-old man who had a constipation problem. You mentioned a couple of medications to take. I am an 82-year-old man, and recently became constipated for a few days. I took Ex-Lax for a couple of days, and it worked. Three days later, I had it again, so I took another Ex-lax or two, and it worked again.

I was sitting in my recliner a few days later when I remembered when I was in my late teens and had the same problem. My mother told me to eat prunes — wow, does that work. Isn’t eating prunes more healthy than taking drugs? My wife and I have been eating about four prunes each evening since, and I have had no problem. We read that eating prunes every day also makes our bones stronger. Is this really true, and how many should a person eat daily? — R.F.P.

Some over-the-counter constipation drugs used to contain phenolphthalein, which is not safe for long-term use. Occasional use of senna or docusate (the active ingredients in most OTC brands) is fine.

Prunes are a very effective treatment for constipation for many people. They are a fruit, but being dried, are higher in sugar than many others. Three to four prunes a day seems reasonable and is effective for many people to treat constipation.

A recent review of studies on the effects of prunes on bone mineral density suggests that there is some benefit. However, the studies were neither consistent nor of high-enough quality that I would recommend prunes solely for their purported benefit on bones. Lastly, the studies used about 100 grams of prunes per day: 10-12 average-size prunes. This is a large sugar load and it also might cause some abdominal distention, especially if a person started out eating 10-12 prunes a day; it’s smarter to increase fiber intake gradually.

Write to Dr. Roach at ToYourGoodHealth @med.cornell.edu.