There is an ongoing controversy about using organic foods instead of conventionally grown or produced foods.
The public, and particularly those members who can afford organically grown or produced food, swear that they are healthier and taste better than ordinary food. Some supermarket chains have climbed on the bandwagon and assure customers that their foods are organically grown and produced.
But what do we really know about organic foods, their health attributes and also their safety?
Unfortunately, not that much. Very few well-controlled scientific studies that compared organic and standard foods in terms of health benefits and safety have been conducted.
However, a fairly recent edition of the Arbor Nutrition Updates (March 2006) reviewed what we know at present about the benefits and potential problems of eating organic foods.
The March 2006 Arbor Nutrition Update lists three studies conducted in the past year that investigated various aspects of organic foods:
1) Do organic foods contain fewer pesticide residues?
In this cross-over study, 23 children (3-11 years of age) were fed conventional foods for five days, then organic foods for five days, and finally conventional foods for another five days. Urine samples were obtained from the children during the 15-day test period and analysed for pesticide residues.
The results showed that the children's urine contained significantly less Malathion and Chlorpyrifos (organophosphorus pesticides) during the phase when they ate organic foods.
This means that eating organic foods that are produced without the use of organophosphorus pesticides leads to a significant reduction in exposure to these pesticides – something people of all ages would benefit by.
The study also showed that the improvement in pesticide exposure was very rapid. Within five days, the children were practically free of contamination.
2) Do organic foods contain more antioxidants and anti-cancer activity?
In this Swedish study, strawberries were cultivated at a research station according to conventional farming practices and by organic methods.
The strawberries were then analysed for antioxidant content and extracts of these strawberries were used to test how efficiently they were able to inhibit human colon and breast cancer cells in the laboratory (note this was not a trial using human subjects).
The results found that the organically grown strawberries contained consistently and significantly more vitamin C and antioxidant phenols. These strawberries also inhibited the growth of colon and breast cancer cells to a significantly greater extent than the strawberries grown by conventional methods.
These results indicate that eating organically grown fruits, like strawberries, will potentially provide more antioxidant protection to humans and that this may inhibit the growth of cancer cells.
3) Are organic foods more contaminated with microorganisms?
Because organic farming makes use of manure and compost, instead of chemical fertilisers, it has been suggested that organically grown foods are more likely to be contaminated with microorganisms which could endanger the user's health.
In an American study, 54 samples of either washed or unwashed salad ingredients from organic farms, where manure was used, and non-organic farms, where conventional fertilisers were used, were analysed for microbial contamination.
Both farming methods produced similar microbial counts (bacteria, yeasts, moulds). This indicates that organically grown foods are not more likely to be contaminated with microbes than foods grown by standard methods, and are just as safe, if not safer.
Is organic food worth the price?
Organic farming is labour intensive and crop production is relatively small compared to usual farming methods. Consequently, organically grown foods are usually much more expensive than standard foods.
The studies discussed above show that organic foods contain significantly fewer pesticide residues than crops grown by conventional methods (this is a great health benefit, especially for our children) and contain more antioxidants, which will benefit people of all ages.
The third study also showed that organic foods are not more contaminated by microorganisms that could endanger health.
So, all in all, these recent studies indicate that organic foods seem to be superior to conventionally grown foods.
But what about the cost? People who are economically advantaged can certainly make use of organically grown foods and thereby boost their health, but what about the millions of economically disadvantaged people who live on the bread line and just cannot afford the luxury of organic foods and their health benefits?
Unless organic farming is given government support and concessions, to help organic farmers to reduce their production costs and bring the price of these foods in line with standard foods, only a small proportion of the population will be able to afford organic foods.
Faced with an ever-increasing population and millions of starving people, the governments of the world are not likely to single out organic farming for subsidies and assistance.
What we now know is that organically grown and produced foods appear to be superior in nutritive content, and contain significantly fewer pesticide residues than conventionally grown foods.
However, these health advantages of organic foods will remain outside the reach of most people who cannot afford the high prices of these foods. This is a great pity. – (Dr Ingrid van Heerden, DietDoc, July 2006)
(Arbor Clinical Nutrition Updates, 2006, No. 242, March)