Association of Frequency of Organic Food Consumption With Cancer Risk

[Graham49]

Findings From the NutriNet-Santé Prospective Cohort Study

Julia Baudry, PhD1; Karen E. Assmann, PhD1; Mathilde Touvier, PhD1; et al. 1Centre de Recherche Epidémiologie et Statistique Sorbonne Paris Cité, Institut National de la Santé et de la Recherche Médicale (INSERM) U1153, Institut National de la Recherche Agronomique (INRA) U1125, Conservatoire National des Arts et Métiers, Université Paris 13, Equipe de Recherche en Epidémiologie Nutritionnelle, Bobigny, France

2Département de Dermatologie, Hôpital St André, Bordeaux, France

3Département de Santé Publique, Hôpital Avicenne, Bobigny, France

4Centre de Recherche en Cardiovasculaire et Nutrition, Aix Marseille Université, INSERM, INRA, Marseille, France

JAMA Intern Med. Published online October 22, 2018. doi:10.1001/jamainternmed.2018.4357

Abstract

Importance 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.

Objective To prospectively investigate the association between organic food consumption and the risk of cancer in a large cohort of French adults.

Design, Setting, and Participants In this population-based prospective cohort study among French adult volunteers, data were included from participants with available information on organic food consumption frequency and dietary intake. For 16 products, participants reported their consumption frequency of labeled organic foods (never, occasionally, or most of the time). An organic food score was then computed (range, 0-32 points). The follow-up dates were May 10, 2009, to November 30, 2016.

Main Outcomes and Measures This study estimated the risk of cancer in association with the organic food score (modeled as quartiles) using Cox proportional hazards regression models adjusted for potential cancer risk factors.

Results Among 68 946 participants (78.0% female; mean [SD] age at baseline, 44.2 [14.5] years), 1340 first incident cancer cases were identified during follow-up, with the most prevalent being 459 breast cancers, 180 prostate cancers, 135 skin cancers, 99 colorectal cancers, 47 non-Hodgkin lymphomas, and 15 other lymphomas. High organic food scores were inversely associated with the overall risk of cancer (hazard ratio for quartile 4 vs quartile 1, 0.75; 95% CI, 0.63-0.88; P for trend = .001; absolute risk reduction, 0.6%; hazard ratio for a 5-point increase, 0.92; 95% CI, 0.88-0.96).

Conclusions and Relevance A higher frequency of organic food consumption was associated with a reduced risk of cancer. Although the study findings need to be confirmed, promoting organic food consumption in the general population could be a promising preventive strategy against cancer.

[pjoshea13]

Unfortunately, those who consume significant amounts of organic produce probably differ in other lifestyle ways from those who never buy organic. Are the chemicals (glyphosate, malathion, diazinon, etc.) the main factor? Hard to tell.

Some can't afford to buy organic, so there is an income/education connection that needs to be adjusted for.

If price were not an obstacle, we might all eat organic. Why not? But the study seems not to have found reduced risk for PCa [3]/

Note [1]:

"When they considered each type of cancer separately, they found that only three had a statistically significant association with organic food consumption.

One of them was postmenopausal breast cancer: The women who ate organic foods most often were 34 percent less likely to receive this diagnosis than women who ate organic foods the least. (There were hints of reduced risk for premenopausal breast cancers as well, but the difference was smaller and could have been due to chance.)

"Another was non-Hodgkin's lymphoma: The most frequent eaters of organic foods were 86 percent less likely to get this form of cancer than their counterparts on the other end of the spectrum. The difference between the two groups was just barely big enough to be statistically significant.

"The last category was all lymphomas: People who ate organic food most often were 76 percent less likely to get cancers of the lymph system than people who ate organic foods the least."

Here is an analysis from someone who has seen the full text: [2].

***

[3]:

Prof Tom Sanders, Professor emeritus of Nutrition and Dietetics at King’s College London, said:

“This an observational study, not a controlled trial. The participants who reported eating organic food most frequently were more likely to be non-smokers, had a lower body mass index (less obesity) and drank less alcohol – all factors that would be expected to result in fewer cases of cancer in this group. There were no significant differences in common sites of cancer such as those of the breast, prostate or colon but there was a lower risk of lymphomas.

“Lymphomas can be causes by viruses (e.g. Hodgkin’s lymphoma) but can also be caused by chronic inflammation (e.g. coeliac disease) as well as some chemicals (certain weedkillers). This finding of a lower incidence of non-Hodgkin’s lymphoma is similar to findings in a UK study.

“Although this present study tried to adjust for known risk factors in the statistical analysis, residual confounding is still likely. Consequently, it is uncertain whether this effect is due to lifestyle differences in people who chose organic food or their lack of exposure to chemicals in non-organic food. Furthermore, the number of cases of non-Hodgkin’s lymphoma was small in relation to the more common causes of cancer.

“Their conclusion, that promoting organic food in the general population could be a promising cancer preventive strategy, is overblown.”

-Patrick

[1] medicalxpress.com/news/2018...

[2] tdaynard.com/2018/10/26/com...

[3] sciencemediacentre.org/expe...

[Graham49 in reply to pjoshea13]

Thanks Patrick

[Graham49]

Thanks Nalakrats