Clueless About Cancer Prevention
A new study has shown that most U.S. adults are unsure how to lower their risk of cancer. Of 1,000 people surveyed, only 38 percent strongly agreed that a diet rich in vegetables and fruits reduces cancer risk. Half the respondents considered exercise beneficial. And a mere one-third believed that maintaining a healthy weight was important. In fact, all three are known to lower risks for many types of cancer.
American Society of Clinical Oncology
Broccoli Family Studied for Cancer-Fighting Power
It’s clear that men who eat more cruciferous vegetables (broccoli, cauliflower, kale, Brussels sprouts, and cabbage) are less likely to develop prostate cancer. Now researchers at the University of California at Berkeley are investigating whether the vegetables’ natural cancer-fighting chemicals could help treat the disease as well. The chemical 3,3'-diindolylmethane, known as DIM, caused prostate cancer cells in a test tube to grow 70 percent more slowly than untreated cells, apparently by blocking signals from male sex hormones. DIM appears to be a unique, naturally occurring chemical that offers preventive and therapeutic usefulness against the most commonly diagnosed cancer in America—prostate cancer.
Le HT, Schaldach CM, Firestone GL, Bjeldanes LF. Plant-derived 3,3'-diindolylmethane is a strong androgen antagonist in human prostate cancer cells. J Biol Chem. 2003;278:21136-21145.
Obese Men at Higher Risk for Prostate Cancer
Researchers in France found that obese men may be more than twice as likely to develop prostate cancer than those who are nearer their normal weight. As reported in the British Journal of Urology International, 194 prostate cancer patients and 194 men being treated for benign prostatic hyperplasia were studied. Men with a body mass index of 25 to 30 (indicating moderate overweight) did not show an increased risk, while those with a BMI of 29 or higher (indicating obesity) had a 2.5-times greater risk of prostate cancer. Swedish, Danish, and Italian studies have produced similar findings.
Irani J, Lefebvre O, Murat F, Dahmani L, Dore B. Obesity in relation to prostate cancer risk: comparison with a population having benign prostatic hyperplasia. BJU Int. 2003;91:482-484.
Miso Soup Protects Women from Breast Cancer
In a prospective cohort cancer study, researchers in Japan tracked more than 20,000 women aged 40 to 59 for more than 10 years, studying their intake of soy foods. As reported in the Journal of the National Cancer Institute, they found that women who consumed miso (fermented soybean paste) soup most frequently (three or more bowls daily) had half the breast cancer risk of those who ate the least (less than one bowl daily). Laboratory studies have previously demonstrated that isoflavones, abundant in soybeans, inhibit hormone-related cancers.
Yamamoto S, Sobue T, Kobayashi M, Sasaki S, Tsugane S. Soy, isoflavone, and breast cancer risk in Japan. JNCI. 2003;95:906-913.
HRT: Promoting Cancer, Hindering Diagnosis
The Women’s Health Initiative trial of combined estrogen and progestin ended early when overall risks, including invasive breast cancer, proved too dangerous. Taking a closer look at the data, researchers found that women who took combination hormone pills not only faced a 24 percent increase in breast cancer risk, but developed larger, more aggressive tumors, which spread more quickly and escaped detection more frequently. They also had significantly more abnormal mammograms. The analysis, detailed in the Journal of the American Medical Association, involved 16,608 postmenopausal women with no prior hysterectomy, aged 50 to 79, who were prescribed either hormones or placebo for an average of five years.
Chlebowski RT, Hendrix SL, Langer RD, et al. Influence of estrogen plus progestin on breast cancer and mammography in healthy postmenopausal women. JAMA. 2003;289:3243-3254.
High-Fiber Diet Cuts Colon Cancer Risk in Half
Results from the European Prospective Investigation into Cancer (EPIC), as reported in The Lancet, found that individuals who consumed the most dietary fiber had a 40 percent reduction in colon cancer risk than those who consumed the least.
This was the largest scientific study of diet and cancer to date, tracking 519,978 subjects in 10 European countries for an average of 4.5 years. A particular strength of the study was its ability to compare widely varying diets. A 1997 report from the World Cancer Research Fund emphasized the importance of consuming a diet high in fruits, vegetables, whole grains, and beans for preventing several cancers including colon cancer. This latest study offers considerable evidence supporting the use of a plant-based diet for colon cancer prevention.
Bingham SA, Day NE, Luben R, et al. Dietary fibre in food and protection against colorectal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC): an observational study. Lancet. 2003;361:1496-1501.
Smoking Increases Familial Pancreatic Cancer Risk
Smoking is a strong risk factor for familial pancreatic cancer, especially for men under 50, according to researchers from the University of Washington who conducted a case-control study of 251 members from 28 families where two or more members of each family had the disease. Smokers had quadruple the risk of developing cancer. Moreover, they developed the disease a full decade earlier than their nonsmoking peers.
Approximately 30,000 cases of pancreatic cancer were diagnosed in 2003, ten percent of which were influenced by heredity.
Rulyak SJ, Lowenfels AB, Maisonneuve P, Brentnall TA. Risk factors for the development of pancreatic cancer in familial pancreatic cancer kindreds. Gastroenterology. 2003;124:1292-9.