Oliver Moore believes the health benefits of organic products should be examined on a case-by-case basis
Is organic food healthier than conventional food? While the environmental and animal welfare benefits of organic are clear and well backed up by research, the jury is still out on the health benefits or otherwise of organic.
Regarding health and organics, avoiding generalisations is important - each product should ideally be taken on a case-by-case basis.
Take milk. In Europe, and in particular in the UK and Ireland, organic dairy cows spend far longer grazing in fields than they do in the US, where some large organic operators feed processed pellets to cows in very confined indoor spaces.
Also, in general, the organic feed standards in Europe, particularly in the UK and Ireland, are stronger than in the US. So making comparisons between the EU, especially the UK research into organic milk and the Irish situation makes some sense, but making comparisons between US research and Ireland makes less sense.
In this context, research from the UK and Italy, from 2003 to the present, has shown organic milk to be nutritionally superior. Research from Newcastle University, led by Prof Carlo Leifert, was presented earlier this year. The preliminary results suggest that because organically reared cows consume higher levels of clover, they produce milk which is on average 50 per cent higher in vitamin E, 75 per cent higher in beta carotene (which the body converts into vitamin A) and two-three times higher in lutein and zeaxanthine (antioxidants) than conventional milk.
"Clearly to convince the scientific community as a whole, we need further evidence and the EU Quality Low Input Food project is very much focused on confirming and explaining the differences in milk composition shown in these studies. However, the evidence already available convinces me to pay a little extra for organic milk," Leifert says.
The higher level of antioxidants backs up peer-reviewed research from Italy, in 2003, in work commissioned by the Italian research council, Bergamo. Higher levels of omega 3 essential fatty acids were also discovered. This backs up previous research into omega levels carried out by the University of Aberdeen. The Aberdeen research also found a preferable omega 3 to 6 ratio in organic milk. Organic milk and Dawn's Omega milk retail for a similar price - around €1.20 for a litre in my local supermarket.
While milk is still a regional product in Ireland, other foods, such as fruit and vegetables, are increasingly globalised. The research suggests that while the levels are not always substantially higher, organic fruit and vegetables can be more nutritious than conventional ones.
A 2001 review of research into fruits, vegetables and grains found that organic crops had significantly higher levels of all 21 nutrients analysed compared with conventional produce, including vitamin C (27 per cent more), magnesium (29 per cent more), iron (21 per cent more) and phosphorous (14 per cent more). Organic lettuce, spinach, cabbage and potatoes showed very high levels of minerals, according to the research, published in the Journal of Complementary Medicine.
Not all research suggests that organic food is more nutritious than conventional food. Research by UCC's department of nutrition found no significant nutritional benefits to organic meat. However, it is rare to find research which suggests that conventional food is more nutritious than organic food.
In addition to health, safety is also a concern. Conflicting research on the dangers of some food additives such as aspartame and tartrazine exist. Hydrogenated fats have been linked to heart disease. While they occur naturally in animals, the industrial process of hydrogenation is banned under organic regulations. While there is debate over levels, some pesticides are known endocrine disruptors. There are concerns over pesticides and a range of conditions, from neurobehavioural and neurotoxic effects to allergic and immuno-regulatory disorders.
However, with chemicals, there is another issue. According to Dr Vyvyan Howard, a toxico-pathologist from the University of Liverpool, "we have traces of 300-500 potentially harmful chemicals in our bodies which have only been around for the last 50 years and which we have ingested through our foods. At present official safety limits are based on studies of agri-chemicals acting alone. There are no toxicological tests of chemical combinations, despite the fact that studies have suggested that their combined impact, or cocktail effect, can make their impact much more powerful. Eating organically grown food is an efficient way for people to avoid these chemicals."
Kildare-based GP Elizabeth Cullen says "pesticides are designed to be hazardous to living creatures; we don't know the long-term effects of the accumulation of these chemicals".
For consumers of organic food, there is some back-up regarding health and safety benefits but there is also uncertainty stemming from conflicting research and a lack of research into particular areas. So yes, the jury is still out, but while they're deliberating, I'll bet some jurors are snacking on organic food.
• Oliver Moore is a doctoral researcher, based in Sligo Institute of Technology. His main research area is organic food and trust.
• National Organic week runs from November 7th-13th. See www.bordbia.ie or tel: 01-6685155 for details.