Sunday, October 21, 2012

Do Multivitamins Prevent Cancer? Part 2

The media is having a field day with the recent study titled Physician Health Study II (PHS II) which claims that multivitamins may slightly decrease cancer rates among men.  If you simply read the headlines and you are a man that wants to decrease your risk of developing cancer, you would think that you should immediately run out and buy a multivitamin, and if you are taking one, you should keep taking it.


The results are not quite living up to all the hype.

According to the study, after 11.4 years of taking multivitamins, only men, predominantly older than 70, showed mild decreases in certain cancers. In fact, this study included men who had previously been diagnosed with cancer, among whom for some unknown reasons were found the best results.

This study, paid for by the multivitamin manufacturers, including Pfizer, actually showed the following:

Slight increases in prostate cancer (662 placebo takers versus 667 among multivitamin users) and melanoma (89 increased to 100).
Slight decreases in total cancer (1253 to 1195).
Slight decrease in colon cancer (95 to 88).
Total mortality (death) slightly decreased from 1,134 to 1,092. That means for over 13,000 total men in the study, there were still over 2,200 deaths and only a decrease of 42 total deaths.

Get this. By my calculation, over 26,000,000 (million) pills over 11 years were taken by 6,660 men to spare 42 deaths. Ouch!  No wonder the drug companies want to push the results of such a study.

Basically, the men who took a daily multivitamin for over 11 years so no improvement in prostate, colon, and bladder cancer and no change in their overall cancer mortality. Also, a careful review of the study shows that the multivitamin users were also slightly less likely to smoke and slightly more likely to eat fruits and vegetables.

Finally, the study did not identify if any of the men had vitamin deficiencies prior to the start of the study. As they focused on physicians, who generally work long hours, there is a high probability that these men spent little time in the sun and therefore had an increased risk of Vitamin D inadequacy or deficiency.

Ladies and gentleman, overall, this study and the numbers presented basically prove nothing. With the overall cancer rate decreasing from 18.4 to 17.6 for every 1,000 years, there remains no reason to believe that multivitamins offer any benefit in the absence of deficiency.

The bottom line is that most importantly, despite taking a multivitamin every day, about 20% of the men still developed cancer and about 20% died.  Save your money!

So once again you are chastened to remember, Caveat Lector! (Let the reader beware).

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