"Eating Right" - More Behavioral Factors
Reference 2 deals with the impact of the Mediterranean Diet on epithelial cancer - cancer of cells that form the covering of most internal and external surfaces of the body and its organs. This includes digestive tract cancers, breast, female genital tract, urinary tract and a few other cancers. The data are taken from studies conducted in Italy between 1983 to 1998. They included more than 12,000 cases of various types of cancer, and 10,000 controls. For the highest intake of vegetables, they find a risk reduction of 0.3 (70%) compared to the lowest intake (no Margin of Error provided). The risk ratio for the highest meat intake (7 or more servings per week) compared with the lowest (less than 4 servings per week) was 1.7 for stomach, 2.0 for colon, 1.9 for rectal, 1.6 for pancreas, 1.5 for bladder, 1.5 for endometrial and 1.3
for ovarian cancers. For comparison, fish intake seems to reduce the risk of several common cancers, mostly of the digestive tract. Comparing the effect of whole-grain foods with the intake of refined foods, this study finds that whole-grains confer significant cancer protection, whereas refined grains lead to an increased cancer risk.
Reference 3 presents results of a major Swedish study that has just been completed. The study examines the combined effect of diet and lifestyle on the frequency of myocardial infarction (heart attack) in women. The study population included 24,444 healthy
women, between the age of 48 to 83 years, at the start of follow-up, and tracked for 6 years. Each participant was given a food frequency questionnaire containing questions about 96 commonly eaten foods. They gathered information on level of educational achievement, family history of heart problems in parents or siblings younger than 60, cholesterol levels, hypertension, use of hormone therapy and aspirin, history of smoking, and waist and hip circumferences. Physical activity was assessed with a questionnaire that included questions on time spent walking or bicycling.
The women with the most healthy diet pattern consumed almost 4 times more higher weekly consumption of vegetables and fruits, 3 times more legumes, 70% more fish, more than twice the intake of vitamin C, compared to the women in the least healthy pattern. This resulted in a risk reduction of 0.7 (30%) with a Margin of Error between 0.6 and 0.9 (10% to 40%). Women who drank alcohol in moderation (roughly 5 grams per day), had a risk reduction of 0.6 (40%) with a Margin of Error between 0.5 and 0.8 (20% to 50%). Physical activity that included 40 min of walking or bicycling daily,
and 1 hour each week of exercise reduced the risk by 0.8 (20% with a Margin of Error between 0.6 and 1.0). Having a waist-to-hip ratio below 0.85 resulted in an additional reduction in risk by 0.8 (20% with a Margin of Error between 0.6 and 1.0).
If one were able to combine all the risk reduction factors (High vegetable intake, alcohol consumption of about 5 grams/day, no current smoking, physically active (40 minutes a day or more of walking or bicycling, one hour per week of exercise, and waist to hip ratio below 0.85), one would expect a risk reduction of 0.22 (78%) with a Margin of Error between 0.07-0.70 (30% to 93%).