Using Food Studies to Reduce Your Risk of Breast Cancer
Almost every day I hear about a new food study. Food A stops cancer! Two weeks later—Food A causes high blood pressure. It’s so hard to decide what to eat that many people just throw up their hands and ignore research that could make their lives better.
So how do you make sense of all of the hype about certain foods? Recently I saw several articles about how walnuts may prevent breast cancer, so I decided to do some investigating and use the walnut study as a way to look at interpreting food studies in general. The reporter’s questions—who, where, when, how, and why—can be very helpful guides to evaluating research.
Who did the research and where was it done and published? The researcher should be associated with a reputable research facility like a university or NIH, and the research should be published in an unbiased scientific forum. In the walnut study the primary researcher Dr. Elaine Hardman, a professor at Marshall University presented her study at American Association for Cancer Research (AACR). So far so good. These are very credible institutions, and I know that before a paper is accepted for presentation at the AACR, other scientists have reviewed it. When someone trying to sell me a product claims that studies prove it’s good for me, but can’t supply chapter and verse of the research, I’m skeptical.
However, in digging a little deeper, I learn more about who actually paid for the study. The Marshal University website says, “The project was funded through grants from the American Institute for Cancer Research and the California Walnut Commission, neither of which had input on the interpretation or reporting of the findings.” Now this is not a deal breaker—in fact, it is very common for funding in research to come from groups who have a financial interest in the outcome. It’s only natural that walnut growers would want evidence of how healthy their product is and be willing to pay to get the scientific data to prove it. And much of the funding came from the American Institute for Cancer Research, not the walnut folks. Nevertheless, I’ll keep this detail in the back of my mind as I try to interpret the results.
When was the study done? This is a recent study with the findings presented in 2009, so it is up to date. Even if the study were old, I wouldn’t necessarily discount it, but I would also want to check to see if there was more recent data.
How was the study conducted? Two groups of mice were injected with breast cancer cells. Then one group received a diet rich in walnuts (equivalent to two ounces a day for humans) while the control group did not.
Having a control group like this study does makes it more trustworthy. It would be good if a follow-up study found the same results in humans; however, food studies in humans are difficult to do. It would take 50 years or more to find out if a walnut-rich diet prevented breast cancer in humans; and humans aren’t very cooperative in following experimental diets.
What did the study find? The walnut-fed mice had significantly fewer tumors, and those who did develop tumors had smaller, slower-growing ones. This is very good news and one of the most conclusive connections between food and cancer that I’ve seen. Usually the data is less directly linked.
Why? This can be the hardest part to understand of any study. The AACR press release on the walnut research explains it this way, “Walnut consumption may provide the body with essential omega-3 fatty acids, antioxidants and phytosterols that reduce the risk of breast cancer. . . . Elaine Hardman, Ph.D., associate professor of medicine at Marshall University School of Medicine, said that while her study was done with laboratory animals rather than humans, people should heed the recommendation to eat more walnuts.
‘Walnuts are better than cookies, french fries or potato chips when you need a snack,’ said Hardman. ‘We know that a healthy diet overall prevents all manner of chronic diseases.’"
Now what? So what am I going to do with this information? If I hated walnuts or was allergic to them, I would ignore it. People are always touting the specific health benefits of particular foods, but few of us are going to make a radical change in our diet and eat foods we hate—at least not for very long.
But I do like walnuts, and I find this study fits into other information that I’ve been reading about how heart healthy nuts are in general and walnuts are in particular. In the study, the mice received the equivalent of two servings of walnuts a day in human dietary terms; that would be almost 400 calories worth of walnuts a day. A teenager with a high metabolism might be able to eat that many calories, especially if the walnuts were substituting for empty calories she used to waste on soda and chips.
But I don’t have that many calories to spare in my diet, so I’ll probably be adding walnuts to oatmeal, salads and baked goods more often, but not two servings a day. I'll probably take some to work to ward off my late afternoon cravings for something sweet.
I’ve made other incremental changes to my diet based on research, especially in varying the colors of the foods I eat: red and green cabbage; blueberries, strawberries, and blackberries; red, green, yellow, and orange peppers. I don’t usually spend as much time digging into the background as I did for the walnut study, but I don’t buy new products until I read more than just the label at the health food store.
Taking the time to learn more about your food choices will make you a more informed consumer. And eating better will help you feel better and may prevent cancer and other health problems. There is no point in jumping on a bandwagon for the latest fad food if you don’t like it, but paying attention to food research and making gradual changes in your diet to more healthy foods makes sense.