Dietary Fiber, Weight Loss Programs, the Prostate, and Your Health

There have been three recent research studies that provide important health news with wide impact. There is more evidence that fiber is good for you, that group weight loss programs appear to be better than individual counseling, and finally that we still don't know for sure how to best screen for prostate cancer.

1. An interesting study looked whole fiber intake and colorectal cancer. The type of study used was a meta-analysis of the existing literature. They found dietary fiber was associated with a decreased risk of colon cancer. The best fiber was cereal fiber or whole grains. Keep in mind, association does not equal causation, so we don't know if it is the fiber, or the displacement of junk food that is causing the improved risk profile. This is yet another study showing that by dietary changes, we can lower our risk of cancer.

2. Another important study looked which weight loss program was better: education given within a primary care office, or a commercial program. The education given within a clinic setting did not show any improvement, and was the most expensive. The commercial programs, were cheaper and did show effectiveness at one year. The best group appeared to be those participating in the Weight Watchers commercial weight loss program, who lost on average about 10 lbs at one year. In England, health care is run by the government, so one possible conclusion is that private commercial programs (in particular Weight Watchers) work better than government run programs (primary care clinic counseling). However, this appears to be a matter of individual versus group therapy: group programs appear to be more successful than individual one-on-one counseling in terms of losing weight.

3. Finally, the U.S. Preventive Services Task Force (USPSTF) has recommended against blood testing for prostate-specific antigen (PSA) as a screening test for prostate cancer. A recent analysis in the New England Journal of Medicine found that there continue to remain several unresolved issues: who should initiate testing? How should the results be handled? Are there important ethnic issues? Nevertheless, they fully support the USPSTF decision to recommend against PSA based screening for prostate cancer.

These three studies are important because they focus our attention on what is likely to be the greatest gains in health this 21st century: behavioral changes and growth in knowledge. These three studies suggest that we are pretty confident at this point that most people would benefit from an increase in fiber in their diet (especially cereal fibers and whole grains). Getting together with some friends and participating in a group weight loss program is probably better than going it alone or just talking with your doctor. Finally, testing your blood for PSA levels right now does not appear to be useful in screening most men for prostate cancer. The authors of the PSA study believe that it is better to focus our efforts on higher payoff investments, such as better insurance coverage and greater investments in commercial weight loss programs.

As a family physician for almost 20 years now, my primary objective with my patients has been to prevent disease, and when that is not possible, to detect disease early while it can be best treated. These studies on fiber, weight loss, and cancer screening provide useful tools to accomplish that task.

REFERENCES

Aune D. Dietary fibre, whole grains, and risk of colorectal cancer: systematic review and dose-response meta-analysis of prospective studies. [2011]

Brett AS, Ablin RJ. Prostate-cancer screening - what the u.s. Preventive services task force left out. [2011]

Heston TF. MegaSimple Diet Plan. [2011]

Jolly K et al. Comparison of range of commercial or primary care led weight reduction programmes with minimal intervention control for weight loss in obesity: Lighten Up randomised controlled trial.