Organic food and the environment, do they help each other?
Professor Ian Givens, from the University's Food Chain and Health Research Theme, describes the current thinking in this area.
In the last two decades has there been a marked increase in demand for organic produce although the reasons for this are complex. Organic food is usually promoted as containing fewer contaminants and more nutrients as well as having a positive effect on the environment. On the other hand there have also been suggestions of potentially harmful consequences of organic production. Whilst most attention has been on how producing organic foods may help the environment, it is not at all known with certainty what affect a wide range of environmental factors might have on organic food.
Are there measureable health benefits from eating organic rather than conventionally produced food?
For many nutrients (such as omega-3 fatty acids, selenium and flavonoids), little information exists to allow a true comparison to be made between the nutritional value of organic food with conventionally produced foods. This is perhaps surprising given the amount of discussion there has been on this in the popular media. Interestingly there is some evidence that organic milk may contain more omega-3 fatty acids than conventional milk. On the surface this sounds like really good news, but the type of the additional omega-3 is actually not one which is very active or useful in humans so in fact there is little benefit.
How does the environment impact on any possible health benefits?
By eating organic foods, our dietary exposure to man-made pesticides and nitrates is likely to be significantly lower, although there is good evidence that the amounts now present in conventional foods are not a health concern. Indeed there is some new and potentially controversial evidence that a small amount of nitrate in the diet is a good thing and a bit more would give a health benefit!
The risk of getting food poisoning (microbiological contamination) is no greater with organic than conventional foods. This means that it is important to maintain good hygiene practices for both types of foods throughout the food supply chain.
Organic foods may have higher levels of antioxidants such as flavonoids and other beneficial plant-derived substances than conventional foods, but this amount is very variable. These levels are highly dependent on factors such as light, soil composition, chemical treatments, storage and marketing factors, so are difficult to measure.
How do the public perceive these benefits?
Regardless of whether any measurable health benefits exist from consumption of organic produce, the public perception of health gains associated with organic produce is undoubtedly influenced by statements that are not (yet) able to be supported by scientific evidence. The increased demand for organic products has been underpinned by growing health and safety related concerns about food consumption. Whilst organic consumers attach more importance than others to the environmental aspects of food production, perceived health benefits are a big driver for organic purchase. It also seems that concerns about issues including chemical residues and Genetic Modification (GM) exceed the desire for better nutritional content.
There is a need for new information which would allow true comparisons to be made between foods produced by organic and conventional approaches. We should also remember that a certain amount of caution is needed when reading reports on what are portrayed as 'certain facts' in the media especially on a subject as emotive as organic food.
This article is based on findings from a prestigious international workshop examining the effects of the environment on the health benefits of organic food which was recently hosted by the University's Food Chain and Health research theme. The event was funded via a grant from the Natural Environment Research Council's Environment and Human Health programme and the outcomes of the workshop are in the process of being published as a book:
Organic Food and Health: Effects of the Environment. Editors: D. I. Givens, S. J. Baxter, A.-M. Minihane and E. J. Shaw. CABI Publishing Ltd., Wallingford.