Organic food isn’t always best – study
VANCOUVER Buying organic food may not always be a better choice to help the planet or human health than cheaper options grown with artificial pesticides, according to researchers.
Birds and bees tend to be more abundant on organic farms, but the benefits may be cancelled out because these farms produce an average of 19 to 25 per cent less food per acre than conventional farms.
This means that more land is needed to produce the same amount of food – and land conversion for agriculture is one of the greatest threats to wildlife, researchers at the University of British Columbia said.
Organic farms tended to use less energy and produce lower emissions, but ‘‘when lower organic yields are taken into account, greenhouse gas emissions might actually be higher under organic management’’, said the authors of the study, published in Science Advances.
‘‘We don’t know whether organic agriculture provides any benefits for biodiversity if lower organic yields are taken into account,’’ the researchers wrote.
They said organic farms tended to cause less nitrogen and phosphorus pollution of water systems, but the lower yields could mean that nitrogen loss per unit of food produced was higher than on conventional farms.
The authors argued that in countries like Canada, where pesticide regulations are stringent and diets are rich in micronutrients, the health benefits of choosing organic may be marginal.
They said organically grown food probably contained slightly more micronutrients, but it was not clear whether this provided ‘‘any actual health benefits to consumers’’.
The team analysed organic crop farming across 17 criteria, including yield, impact on climate change, farmer livelihood and consumer health.
‘‘Organic is often proposed as a holy grail solution to current environmental and food scarcity problems, but we found that the costs and benefits will vary heavily depending on the context,’’ said Verena Seufert, one of the authors.
They concluded that organic farming was not the only solution to providing a sustainable source of food for an ever-growing global population, but it still had an important role to play.
‘‘We need to stop thinking of organic and conventional agriculture as two ends of the spectrum. Instead, consumers should demand better practices for both so that we can achieve the world’s food needs in a sustainable way,’’ said Seufert.
The study, which involved a review of the scientific literature on the environmental and economic performance of organic farms, also found that they were highly dependent on animal manure from conventional farms.
‘‘It is not clear whether we would have enough organic fertilisers to feed everyone in the world with organic food.’’
Organic food was also more expensive and ‘‘therefore less accessible to consumers with low income’’, the researchers said.
This week the Environmental Working Group, which calls itself a non-partisan organisation REUTERS aimed at protecting human health and the environment, released its annual ranking of the best (‘‘Clean Fifteen’’) and worst (‘‘Dirty Dozen’’) produce in the United States when it comes to pesticide content.
Strawberries and spinach took the top two spots in this year’s Dirty Dozen – more than 98 per cent of samples tested positive for pesticide residue – . while the Clean Fifteen includes sweetcorn, mangoes, eggplant and cabbage.
However, experts in pesticides and toxicology say that just because pesticides are on produce, it doesn’t mean the produce is dangerous – it is the level of residue that matters. The Times, Bloomberg