Press release: Workshop – The impact of organic food on human health

The workshop on “The impact of organic food on human health” was organized by the European Parliament’s Science and Technology Options Assessment (STOA) unit, on 18/11/2015. In the STOA workshop, experts from different EU countries discussed the current knowledge about the effects of organic foods on human health. First speaker, Dr Axel Mie pointed out that some of the mediators that could lead to potential effects in organic farming are the following:

  1. Use of antibiotics: Since the antibiotics are used only to treat sick animals, this could potentially lead to decreased development of antibiotic resistant bacteria which is a benefit for human health.
  2. Plant protection: No pesticides are used; hence humans have lower pesticide exposures.
  3. Plant nutrient availability: No fertilizers are allowed; hence more nutritive varieties are developed.

He noted that organic milk contains 60% more ω-3 fatty acids because organic dairy cows have higher access to pasture and if we convert from conventional to organic milk products, we will have 4% increase of ω-3 intake. This looks like a small percentage, but ω-3 are important for the brain and neural development. In the KOALA cohort study, it has been found that increased ω-3 concentration in breast milk is associated with decreased allergy risk at 1 year of age. Second speaker, Dr Johannes Kahl referred to the environmental impacts of organic farming systems and more specifically to the fact the organic performs better than non- organic when calculated per area unit, but if it is calculated per kg there is no difference between the farming systems or organic performs worse. Moreover, organic farming shows 30% higher species richness than non-organic and potentially offers a means of returning functional evenness into ecosystems. Regarding the impact of organic food system on nutrition, meta-analysis showed that:

  1. Organic farming potentially enhances phosphorous and diminishes nitrogen content in crops
  2. Organic farming shows higher levels of polyphenols in fruits and vegetables compared to non-organic
  3. Organic foods have tendency for lower pesticide residues and antibiotic-resistant bacteria.

Regarding the impact of organic food system on health, studies showed that:

  1. Flies showed greater fertility, longevity and greater activity and stress-resistance when fed with organic grown feed
  2. Chicken showed enhanced immune reactivity, a stronger reaction to the immune challenge
  3. Women showed less non-Hodgkin lymphoma when eating organic food
  4. Organic diet significantly reduced pesticide exposure in adults and is significantly associated with reduced urinary concentration of pesticide residues in children
  5. Children showed reduced risk of allergic (IgE) sensitization and lower prevalence of atopic diseases when fed with organic diet

Also, Dr Kahl referred to the Organic Food System Program (OFSP), which was developed beginning of 2015 with 45 partners involved from 27 countries. The current status quo is that consumers of organic products seem to share specific attitudes to food and other food consumption characteristics (less meat, more fruit and vegetables etc.). Hence, one of the hypothesis that led to the development of OFSP is “Could these attitudes also drive consumers towards a more sustainable diet?”.

Next, Dr Bernhard Watzl discussed the question “does organic farming induces measurable beneficial health effect beyond those that can be achieved through healthy diet/lifestyle”. The current review studies conclude that evidence is lacking that organic foods are more nutritious than conventional foods and there are certain limitations like high heterogeneity and concern for publication bias, few human intervention studies and no long-term studies of health outcomes of populations.

Mr. Stoiko Apostolov continued by presenting the organic farming case in Bulgaria. He highlighted that the main motivation of the new candidates for organic farmers is still compensatory payment and that organic sector benefits more from scandals associated with the conventional foods and food industry.

Dr Ewa Rembialkowska followed with the topic of “Nutrient composition of organic and conventional crops, and health effects in in vitro and animal studies”. Meta-analysis results showed that there are higher concentrations of polyphenols in organic plant foods and many of these compounds have previously been linked to a reduced risk of chronic diseases, including cardiovascular disease, neurodegenerative diseases and certain cancers. Moreover, lower cadmium and nitrogen concentrations have been found in organically grown crops (48 % less) and four times higher frequency of occurrence of pesticide residues in conventional crops. Also studies on small lab animals showed that when animals are fed with organic products there is a different impact on the physiology of animals, especially their immune system compared to conventional fed animals.

Last, Dr Philippe Grandjean presented about the “Public health effects of pesticide exposure”. He mentioned that the use of pesticides is widespread and it corresponds to 0.3 kg per inhabitant per year. The pesticide exposure comes from multiple sources and the major route is fruits and vegetables. Pesticide residues are detected in 50% of fruit, vegetables and cereals and over 25% contain more than one pesticide. According to the legislation, the food limits are not exceeded, however they are not based on developmental neurotoxicity as critical effect. Children with prenatal pesticide exposure have been found to have difficulty with coordination of motor function (finger opposition test), be 2 years behind in development of visuospatial function at age 8 years and loss of IQ points. As a final comment, he highlighted the need for precautionary action to protect brain development.

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