BUFFALO, N.Y. -- Plant-based fats may cut the risk of prostate cancer by reducing the levels of both testosterone and certain enzymes that metabolize testosterone into more active forms, a new study by University at Buffalo nutrition researchers has shown.
The study, published recently in the Journal of Nutritional Biochemistry, reported that feeding rats a diet rich in phytosterols, the type of fat found in plants, reduced testosterone in the blood stream by 33 percent. A high level of testosterone has been implicated as a risk factor for developing prostate cancer.
The levels of two enzymes -- 5-a reductase and aromatase -- that metabolize testosterone into end products that also are implicated in the development of prostate cancer were reduced by 44 percent and 55 percent respectively, results showed.
Lead researcher Atif Awad, Ph.D., director of UB's Nutrition Program, and colleagues have been trying to understand the mechanisms responsible for vegetarians' lower rates of hormone-dependent cancers, and for the lower mortality rate from prostate cancer in Asian countries, where populations eat little meat. Awad is an associate professor in the Department of Physical Therapy, Exercise and Nutrition Sciences in the UB School of Health Related Professions.
With fats known to play a role in the development of several cancers,
Awad's group has been focusing on the phytosterols for possible answers. He
reported at an international conference on cancer research in Greece last
October that the phytosterol B-sitosterol appears to play a role in inhibiting
the growth of human prostate-cancer cells by strengthening an intracellular
signaling system that inhibits cell division. (See previous news release,
"PLANT-BASED FAT INHIBITS CANCER-CELL GROWTH BY ENHANCING CELL'S SIGNALING
SYSTEM, UB RESEARCHERS SHOW," at http://www.buffalo.edu/news/Latest/AwadPhyto
Contact: Lois Baker
University at Buffalo