Obesity and PSA Levels

There have been some observations suggesting that obese men have, in general, lower serum prostate-specific antigen (SPA) levels than non-obese men. This may be important, as the PSA level is often used to assess a risk for prostate cancer, or to check on the effectiveness of treatment of prostate cancer. A study reported in the Journal of the American Medical Association confirms this relationship.

About 13,000 men who had radical prostatectomy for prostate cancer provided data for this study. The analysis classified them into 3 groups according their body mass index (BMI ): normal (below 25), overweight (25-30), and obese (over 30). Estimates of plasma volume increased steadily with BMI values. And increasing BMI was linked to lower PSA concentrations in all 3 groups. Men with a BMI over 35 had PSA concentrations that were 11% to 21% lower than those with a normal BMI . The experts believe this is due to the amount of actual PSA substance being diluted in the larger plasma volume associated with overweight.

What’s the relevance of this finding? It means that, if you’re overweight, you shouldn’t be satisfied by a ‘within normal limits’ PSA result, if it’s near the top of the normal range; maybe your “normal” lies a little bit lower, so react accordingly. If necessary, lose some weight!