I'm preventing prostate cancer

Sometimes in medicine, a paper comes out that invites so much humor that it seems a shame to forget it. I was reminded of one such article while reading Vitum's last post.

JAMA in 2004 ran an article about the effect of ejaculation frequency on the risk of prostate cancer. They found that those who reported higher frequency of ejaculation per month were less likely to have prostate cancer. This was a prospective analysis using questionnaires, and had a number of significant questions regarding validity. However, it reinforced a study done by the British Journal of Urology International, where 5 or more ejaculations weekly had a negative association with risk of developing prostate cancer.

My friends and I couldn't get enough of this medical breakthrough. Whenever we wanted to make a masturbation joke, it was couched in terms of prostate cancer risk. "I'm going to decrease my risk for prostate cancer." "I have 3 more to go this week, if I want to keep my cancer risk low." "What have you done to prevent prostate cancer today?"

However, one of my friends made a great comment when he read the article: "Five times a week: prevents prostate cancer. Six times? DEATH!"

Giles GG et al. Sexual factors and prostate cancer. BJU Int. 2003; 92(3): 211-6
Leitzmann MF et al. Ejaculation frequency and subsequent risk of prostate cancer. JAMA. 2004; 291(13): 1578-86.


Anonymous said...

In the article referred to in Vitum's post you wonder how they defined chronic masturbation. Probably a tricky subject for many men.

Anonymous said...

If you read the actual report (not the misleading summaries reported in the news) it states that a high frequency of masturbation only lowers risk for total and organ confined prostate cancer. The risk of getting aggressive prostate cancer, which can actually kill you, is increased in those who masturbate frequently. Also what everyone fails to mention about the study is that they show people who masturbate least frequently, 0- 3 times a month, have a reduced risk of getting prostate cancer. The %33 reduced risk for 21 times a month you read all over the web, is only telative to those in the category that masturbate 4-7 times per month. Read the actual study and don't belive how it is being misrepresented by the press!

Anonymous said...

A link to the actual Jama study that is being misrepresented by the press. Look under tables 1 and tables 3 where they state the lowest frequency of ejaculations are associated with reduced prostate cancer, and higest frequency of ejaculations are associated with INCREASED rish of advanced prostate cancer.

incidental findings said...

I should note a few points in response to the above comments:
(1) I did provide a citation for the article already
(2) The article has some serious issues with validity. There are too many confounding factors, as is true with many cohort studies.
(3) My approval of the above comments in no way is an endorsement of its content.
(4) The article references ejaculatory frequency, and does not specifically address masturbation at all.
(5) The commenter has made some generalizations of the study as well. It would be risky to say that this study shows anything with respect to advanced prostate cancer. The low frequency group ALSO had an increase in advanced disease compared to the 4-7/month group.
(6) Please keep in mind that this blog is not to provide any useful medical information, and the content of this blog is not my professional medical opinion.