Researchers observed a significant reduction in overall risk of cancer among individuals who consumed organic food at a high frequency, according to a new study published in JAMA Internal Medicine.
“Although organic foods are less likely to contain pesticide residues than conventional foods, few studies have examined the association of organic food consumption with cancer risk,” Julia Baudry, PhD, from the Centre de Recherche Epidémiologie et Statistique Sorbonne Paris Cité, Institut National de la Santé et de la Recherche Médicale, France, and colleagues wrote.
Baudry and colleagues conducted a population-based prospective cohort study to determine how an organic food-based diet affects cancer risk. The researchers enrolled 68,946 adult volunteers from France (78% women; mean age at baseline, 44.2 years).
Participants provided information on how frequently they consumed organic products, such as fruits, vegetables, soy-based products, dairy products, meat and fish, eggs, grains and legumes, bread and cereals, flour, vegetable oils and condiments, coffee and tea, wine, and dietary supplements. The researchers measured the frequency of the participants’ consumption of organic products as “never,” “occasionally” or “most of the time.”
Participants were allocated two points for answering “most of the time” and one point for answering “occasionally” for each product for an organic food score of up to 32 points. They were categorized into four quartiles based on the mean organic food score. The first quartile had a mean score of 0.72, the second quartile had a mean score of 4.95, the third quartile had a mean score of 10.36 and the fourth quartile had a mean score of 19.36.
During follow-up, the researchers identified 1,340 first-incident cancer cases; of these, 34.3% were breast cancers, 13.4% were prostate cancers, 10.1% were skin cancers, 7.4% were colorectal cancers, 3.5% were non-Hodgkin lymphomas and 1.1% were other lymphomas.
Participants with the highest organic food scores had a lower overall risk for cancer compared with those with the lowest score (HR for quartile 4 vs. quartile 1 = 0.75; 95% CI, 0.63-0.88; absolute risk reduction = 0.6%; HR for a 5-point increase = 0.92; 95% CI, 0.88-0.96).
Higher organic food consumption was associated with reduced risks for specific cancer sites, including postmenopausal breast cancer, non-Hodgkin lymphomas and all lymphomas.
There was no apparent association between both a high-quality diet and high frequency of organic food consumption and reduced cancer risk compared with a low-quality diet and low frequency of organic food consumption.
“Further prospective studies using accurate exposure data are necessary to confirm these results and should integrate a large number of individuals,” Baudry and colleagues concluded. “Although our findings need to be confirmed, promoting organic food consumption in the general population could be a promising preventive strategy against cancer.”
In an accompanying editorial, Elena C. Hemler, BS, program coordinator at the department of nutrition at Harvard T.H. Chan School of Public Health, and colleagues wrote that the study by Baudry and colleagues indicates an urgent need for more research and validated tools to assess organic food consumption and its association with cancer risk.
“Concerns over pesticide risks should not discourage intake of conventional fruits and vegetables, especially because organic produce is often expensive and inaccessible to many populations. … Current recommendations should continue to focus on modifiable risk factors that are backed by solid evidence and encourage healthy dietary patterns, including higher intake of fruits and vegetables, whether conventional or organic,” they wrote. – by Alaina Tedesco