When cows are in clover humans benefit, too, says organic study

Published on Tuesday 27 May 2008 22:41

ORGANIC milk is significantly richer in nutrients than that from conventional dairy farms, thanks to the cows' diet, a new study has shown.

Researchers found that when cows were grazed outside on grass and clover, they produced milk with higher levels of beneficial fatty acids, antioxidants and vitamins.

The study by Newcastle University showed conjugated linoleic acid (CLA9) – which has been hailed as helping to reduce the risk of cancer – to be 60 per cent higher in organic milk during the summer months.

It also found organic milk has 39 per cent more omega-3 fatty acid and 33 per cent more vitamin E than the non-organic alternative. Both are thought to reduce the risk of cancer and cardiovascular disease.

The greatest difference between organic and non-organic milk was found in summer, when there is a wider discrepancy in feeding techniques.

Gillian Butler, livestock production manager at Nafferton Ecological Farming Group, who led the research, said natural grazing provided around 84 per cent of food for cows on organic farms in the summer, compared to 37 per cent for conventionally farmed animals.

The rest of the non-organic cows' diet was made up of 29 per cent silage (preserved grass) and 34 per cent concentrate (a mixture of cereals).

"We have known for some time that what cows are fed has a big influence on milk quality," Ms Butler said.

"What is different about this research is it clearly shows that on organic farms, letting cows graze naturally, using forage-based diet, is the most important reason for the differences in the composition between organic and conventional milk."

She said she would recommend consumers to drink organic milk throughout the year.

The results of the study are published in the Journal of Science of Food and Agriculture.