Weight gain in middle age may increase risk of prostate cancer
Science is starting to focus on the determining the underlying causes of certain cancers and especially how metabolic problems like obesity and weight gain may potentially contribute. While we know that obesity increases ones risk of colorectal cancer, kidney, esophagus, endometrial and breast cancer, there is new evidence from the University of Hawaii that shows middle age weight gain can confer an increased risk of prostate cancer in men.
Lead researcher Brenda Y. Hernandez, Ph.D., M.P.H., assistant professor at the Cancer Research Center of Hawaii studied a group of 83,879 men who were Hispanics, Japanese, white, Native American and blacks in a prospective study from 1993-1996.
Their data, recently analyzed suggests that excessive weight gain between younger and older adulthood increased the risk of advanced and high-grade prostate cancers in white men and increased the risk of localized and low-grade disease in black men, but decreased the risk of localized prostate cancer in Japanese men.
30 percent of prostate cancer cases occurred among Japanese men, 25 percent among white men, 27 percent among Hispanic men, 13 percent among black men, and 7 percent among Native Hawaiian men.
This difference in incidence of prostate cancer between men of different ethnic groups may be attributed to different proportions of fat to lean mass and where that fat is placed.
While it is difficult to jump to a conclusion that young adulthood weight gain causes prostate cancer, this study definitively shows that at the very least there is a strong correlation. Men at this age are undergoing much change after finishing school, entering new jobs, which may cause changes in eating habits, potential decreases in regular physical activity that results in weight gain.
I usually advise my college patients, especially those that are “retiring” from formal college athletics, that they have spent their lives forming poor eating habits that haven’t manifested in weight gain simply because they have been burning an extreme amount of calories doing sports. When they leave college, all of a sudden they aren’t burning as many calories, and metabolisms slow down yet they continue to eat similar quantities, so rapid weight gain ensues.
This new study is one more reason to encourage healthy eating habits BEFORE finishing college and some argue even before.
References:
1) Cancer Epidemiology, Biomarkers & Prevention, September 1, 2009
2) http://www.cancer.gov/cancertopics/factsheet/risk/obesity
