Food Fad or Good Nutrition? Using Food Studies to Make Healthy Choices

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.