Cooking methods, cancer risk

Example 3. Butler et al. (2003) conducted a population-based case-control study that evaluated levels of HCAs, meat intake according to doneness and cooking method, and the risk of colon cancer. The study population consisted of participants selected from 33 counties in North Carolina who were part of the North Carolina Colon Cancer Study. Cases included 274 blacks and 346 whites, between the ages of 40 and 84 with invasive adenocarcinoma of the colon diagnosed from 1996 to 2000. Controls, 426 blacks and 611 whites, were randomly selected from the North Carolina Division of Motor Vehicles (under 65) and the Center for Medicare and Medicaid services (over 65). Exposure was assessed using a food-frequency questionnaire. Meat intake frequency data, cooking method, and level of doneness was used to estimate exposure values for three specific HCAs. (Results of this study are discussed in Section 26.2.2b.). Source Butler et al. (2003). 

Meat, meat cooking methods and preservahon, and risk for colorectal adenoma. Cancer Res., 65, 8034-8041. 

The ultimate goal is to understand the relationship between HCAs and human cancer and to search for various measures to reduce the risk of, or to prevent, cancer. Food contains a complex mixture of nutrients, vitamins, additives, contaminants, and phytochemicals. The simplest way to reduce risk is to reduce the intakes of HCAs where possible through modified methods of cooking and, at the same time, to encourage the consumption of fruits and vegetables, especially of the cruciferous family. The results presented here support the epidemiological evidence that dietary phytochemicals can protect against cancer [108, 109],... 

While the body of evidence seems strong, several studies have found either no or weak associations between lycopene consumption and disease. Some of this may be explained by the fact that blood lycopene concentrations were much lower in these studies than in those that showed a beneficial effect. Thus, future dietary based studies need to include blood sampling to further define the range of blood concentrations of lycopene in the population, ideally with method standardization so that studies can be directly compared. The prostate cancer association is usually stronger for cooked tomato products rather than raw tomatoes or total lycopene intake. This too supports the idea that it is the whole food, with a broad array of nutrients and nonnutritive bioactive components, that is important for overall health rather than isolated compounds. It is possible that the beneficial effects of tomatoes are increased by preparing a concentrated product that enhances the nutrient bioavailability, as processed and cooked tomatoes are more closely associated to decreased risk of disease than either raw tomatoes or tomato juice. 

---