Friday, December 2, 2011

Flaxseed Can Be Protective Against Prostate Cancer


Duke University Medical Center (http://www.mc.duke.edu/) 
Posted 7/12/2001

http://www.sciencedaily.com/releases/2001/07/010712080024.htm
                 New Pilot Study Suggests Flaxseed And Low-Fat Diet 
                 Can Be Protective Against Prostate Cancer

                 DURHAM, N.C. —- A low-fat diet supplemented with flaxseed may help reduce 
                 the risk of prostate cancer, researchers from Duke University Medical Center report 
                 in the July issue of Urology.

                 The researchers said dietary fat and fiber can affect hormone levels and may 
                 influence cancer progression. Flaxseed is high in fiber and is the richest source 
                 of plant-based, omega-3 fatty acids. Studies suggest that dietary fiber reduces 
                 cancer risk, and omega-3 fatty acids also have shown a protective benefit 
                 against cancer. Flaxseed is also a rich source of lignan, a specific family of 
                 fiber-related compounds that appear to play a key role in influencing both 
                 estrogen and androgen metabolism.

                 “We thought flaxseed would be the perfect food for prostate cancer patients,” 
                 said lead author Wendy Demark-Wahnefried, associate research professor in 
                 the department of surgery at Duke. “It’s full of omega-3 fatty acids, fiber and 
                 lignan. Testosterone may be important in the progression of prostate cancer, 
                 and lignan in the flaxseed binds testosterone, so we thought the flaxseed might 
                 suppress the growth of prostate cancer cells. By pairing a low-fat diet with the 
                 flaxseed supplement, we also thought we could maximize the effect of the 
                 omega-3 fatty acids, since studies in animals show that the kind of fat we eat 
                 may be important for cancer progression.”

                 The pilot study involved 25 patients with prostate cancer who were awaiting 
                 prostatectomy (surgical removal of the prostate). Baseline levels of 
                 prostate-specific antigen (PSA), testosterone, free androgen index and total 
                 serum cholesterol were determined at the beginning of the study. The tumors 
                 of those on the diet were then matched with 25 historic cases, equal in age, 
                 race, PSA level at diagnosis and biopsy Gleason sum (a scoring system used 
                 to grade prostate tumors) to compare tumor progression and biomarkers after 
                 the dietary intervention.

                 The men were on the low-fat, flaxseed-supplemented diet for an average of 
                 34 days. Finely ground flaxseed was used in the study because, in its natural 
                 form, flaxseed is a pointy, tough seed that can puncture the intestines when 
                 consumed in the amounts used in this study (three rounded tablespoons a 
                 day). The ground flaxseed in the study was vacuum-packed (ground flaxseed 
                 can quickly go rancid) and had added emulsifiers for ease of mixing. The men 
                 were instructed to sprinkle the flaxseed on their cereal or mix it into juices, 
                 yogurt or applesauce. Researchers reported good compliance with the diet 
                 and said it was tolerated well.

                 At the end of the study, the researchers observed that the men on the diet had 
                 significant decreases in cholesterol, and both total and free testosterone. While 
                 there was a decrease in testosterone levels, they noted that none of the 
                 participants in the study suffered decreased libido or sexual dysfunction. There 
                 was a trend toward a decrease in PSA levels in men with early-stage prostate 
                 cancer (Gleason sums of six or less), but in men with advanced prostate 
                 cancer (Gleason sums of more than six) PSA levels continued to rise.

                 “It’s not surprising that a diet therapy that was only taken for an average of 34 
                 days had little effect on men with aggressive disease,” Demark-Wahnefried 
                 said. “But what we did see was that for the men on the diet, their tumor cells 
                 did not divide as quickly and there was a greater rate of apoptosis (tumor cell 
                 death) in this group.”

                 With such a short-term dietary intervention, the researchers said they did not 
                 expect to see a difference in tumor biology between the diet-treated patients 
                 and the control patients, but were encouraged by the lower proliferation rates 
                 and significantly higher rates of apoptotic cell death. However, they said the 
                 results should be interpreted with caution, stressing that randomized controlled 
                 clinical trials are needed to confirm the results of the pilot study. Research on 
                 mice models is currently under way, and preliminary results support the 
                 findings in humans.

                 Demark-Wahnefried said it is still unknown if the low fat diet or the 
                 flaxseed—or a combination of the two—is the active component in the tumor 
                 reductions, adding more studies examining these elements independently are 
                 needed.

                 Note: This story has been adapted from a news release issued by Duke University 
                 Medical Center for journalists and other members of the public. If you wish to quote 
                 from any part of this story, please credit Duke University Medical Center as the 
                 original source. You may also wish to include the following link in any citation: 
                 http://www.sciencedaily.com/releases/2001/07/010712080024.htm 

2 comments:

Unknown said...

The study is very useful as it was being done in a medical center.Dr.Budwig'work appeared through the books.Why not in peer reviewed medical journals.Further research confirms beneficial effects of flaxseeds and its oil.

Unknown said...

The above comment was made by A.B.Agarwal