Breast Cancer

Pesticides are Really Bad When it Comes to Cancer, Organic Food is Good — Major New Study

Published Oct 24, 2018

Whether you have strong feelings about organic foods or just casually choose them in the supermarket, a new French study has some encouraging news. People who ate more organic foods had a lower risk for cancer. Nearly 70,000 people in France who regularly recorded their eating habits over five years, had a 25% reduction in their risk of cancer.

Results are of particular interest because of the issue of pesticides in food. The authors noted that “the role of pesticides for the risk of cancer could not be doubted given the growing body of evidence linking cancer development to pesticide exposure.”  An FDA report last year estimated that half of U.S. food contains pesticides. In the United States, “more than 90% of the population have detectable pesticides in their urine and blood.” But there has been very little research done on the link between organic foods and cancer.

In 2009, French researchers began a study where they recruited volunteers to fill out online self-administered questionnaires about their food consumption. The questionnaires asked about the frequency of use of 16 organic products including: fruits, vegetables, dairy, meat, poultry, eggs, grain, bread, cereals, vegetable oils, ready to eat meals, coffee, tea, wine and chocolate.

Participants were also asked about health events, including cancer diagnosis. For each reported case, study physicians followed up with the participant’s doctor to collect additional information about the health event. Key stats to know about the study include:

  • Participants had been followed for a mean of 4 1/2 years
  • 78% were women
  • The average age was 44

Based on their organic food consumption they were divided into four groups. When they compared the group that consumed the least organic food with the group that  consumed the most, there was a 25% reduction in cancer in the group that had the most organic food.

While they looked at a number of different cancers, the reduced risk was only seen in three: post menopausal breast cancer, non-Hodgkin’s lymphoma, and all lymphomas. There was no reduced risk for other cancers. The author said, “to the best of our knowledge, the present study is the first to evaluate frequency of organic food consumption associated with cancer risk using detailed information on exposure.” The results of the study were published in JAMA Internal Medicine.

The French study had a number of strengths. It was a large group of people who were followed over time to determine the association between organic food consumption and cancer risk. But in an accompanying editorial, researchers from Harvard T.H. Chan School of Public Health said it had “significant weaknesses.”  The first was the questionnaire. The editorial said that it was unclear exactly what the questionnaire was measuring, noting that organic food consumption is extremely difficult to measure. Second, The authors suggested that the organic food consumption could be used to determine the level of pesticides in foods. The editorial said that was never proven. The editorial concluded that “at the current stage of research, the relationship between organic food consumption and cancer risk is still unclear.”

For some, this study will provide further support for their belief that organic foods are worth the generally higher cost because of their health benefits. Others may not be convinced there is reason to worry. But no matter what the strength of the evidence, the study is an important reminder that we may be making choices about cancer prevention, when we check out at the supermarket.

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