Økologisk kost og sundhed

Summary

In 2000-2001 a review was produced on the topic "Organic food and human health", (http://www.agrsci.dk/foejo/DK/sider/pub/fojorap.html ).
The review evaluated a large number of studies comparing the constituents of organic and conventional foods, as well as feeding studies comparing reproduction and health of animals fed with organic or conventional feed. Additionally studies on the connection between consumer values and food production systems were reviewed.
The results showed that organic plant foods consistently contain more vitamin C, natural pesticides and higher dry weight percentage, less b-carotene, pesticide residues and protein, but the protein has a higher percentage of essential amino acids than in conventional plants. Organic animal products contain more conjugated linoleic acid (CLA) and unsaturated fatty acid, and less bacteria with resistance to antibiotics, and organic processed products are made with less additives and shorter shelf life, when compared with similar conventional products.
However, on this basis it is not possible to conclude that one or the other type of food is better for health, mainly because the general knowledge of the connection between food and health is not sufficiently detailed to allow such an estimate. Also because whenever a risk is associated with a pesticide or food additive, the substance is withdrawn from the market, making estimates about the present and future situation impossible and some prior studies obsolete.
Animal studies generally showed little difference between the two types of feed, although most of the published studies showed that a small proportion of the measured characteristics differed significantly, in most of these cases indicating better health after the organic feed treatment. The greatest effect overall was on mortality, where 3 of 7 studies showed less mortality with organic feed, while 4 found no difference. However, most studies are outdated, due to changing practices in both organic and conventional agriculture, many have methodological flaws, and under-reporting of inconclusive results is very likely. So these studies can not be taken as evidence for any differential effects of present day organic or conventional food on health of humans.
Consumer surveys show that consumers who consistently prefer organic food are the ones most concerned with food related risks, such as pesticides and bacteria, so it is possible, but not tested, that the availability of organic food provides some consumers with greater well-being through a perception of better safety.
Conclusion: There are consistent differences between organic and conventional foods on several characteristics, but the data are insufficient to conclude if or how this could affect human health.
More knowledge must be gained on the connection between food composition and human health in general, and on which aspects of the production systems that are responsible for the observed differences. This will both allow definitive estimates of the effects of existing production systems on human health, and, equally importantly, enable positive effects to be retained or even improved during future developments of both organic and conventional agriculture.