This week, the Journal of the American Medical Association released a study touting the cancer-fighting effects of organic foods. Headlines blared all over the country that by merely eating organic food, you could reduce your risk of cancer by 25%. As with any study that produces such fantastic conclusions, I wondered, is it true?
Almost 69,000 French adults were asked to fill out an online questionnaire about their eating habits in regards to organic foods over three 24-hour periods, Researchers then followed these participants for five years. Based on the answers in the survey, participants’ diets were given a score. Researchers also gathered other self-reported data, including their height and weight, how much they smoked or drank, occupation, education, household income, and marital status. 78% of study participants were women, and the average age of participants was 44 years old.
During the five year follow-up, about 2% (or 1340) of the participants developed some type of cancer. Researchers found that those who ate more organic foods were less likely to develop postmenopausal breast cancer and Non-Hodgkin’s lymphoma. While that sounds great, keep in mind that this means that the researchers found NO association between eating organic foods and reduction in risk of other cancers, AND the researchers also admit that the absolute risk reduction of any cancer was only 0.6%.
While the study was large, it reports results based on association only—it cannot prove cause and effect. While those who eat more organic food were less likely to develop these two specific types of cancer, was it the organic food that made the difference, or was it something else entirely? The study also falls short in that it was also based on self-report, and intake of organic food was measured using a questionnaire that wasn’t validated, which could make results unreliable.
This study also found that those people who ate more organic foods were more likely to have a “better” job and make more money, drink less alcohol, be a non-smoker, exercise more, and eat less meat and less processed foods. A higher income likely makes it possible for someone to take better care of themselves, go to the doctor more frequently, and treat minor conditions before they become significant problems. Also, people with higher incomes are more likely to be able to afford organic foods. (On average, it costs 45% more in the U.S.)
What Should You Do?
I am always troubled by studies like this, or at least in the headlines reporting them. Scaring people away from conventionally grown produce is a shame because it’s ALL safe to consume. Even study authors admit that any “risks” with conventionally grown produce are outweighed by the benefits of including them in a balanced diet. The choice to purchase organic is one that is often based on income and availability--if you have the money, there is no harm in purchasing the more expensive option, but health benefits are not guaranteed.
Studies show that headlines like these and lists like this impact low-income consumers most significantly. Consumers who were shown informational messages on organic produce were less likely to purchase any fruits and vegetables at all.
Instead of scaring or shaming people into purchasing organic, the focus should be on all health behaviors that lead to a reduction in the risk of cancer and other chronic illnesses. And as always, WASH all your fruits and vegetables before eating--even the organics!