Organic or conventional? Stanford study sparks nutrition debate

A recent Stanford University study comparing organic and conventionally produced food is “irrelevant” for most Australian consumers of organic products, an academic claims.

The Stanford study, led by Dena Bravata and co-authored by Crystal Smith-Spangler, found no strong evidence to suggest that organic foods are more nutritious or carry fewer health risks than conventionally produced foods. It did, however, find that consumption of organic foods can reduce the risk of pesticide exposure.

But RMIT lecturer Liza Oates says this is not surprising. “There are a huge number of factors that affect nutrient levels in food,” Oates said. “So, it is almost inevitable that trying to isolate one factor, such as the farming method, to explain these nutritional differences will be problematic.”

It’s also not relevant for Australian consumers, Oates says. “The study is based on a meta-analysis of existing data that is trying to generalise by looking at foods from different growing seasons, climates and soils and it doesn’t relate to Australian farms.”

But consumers don’t necessarily opt for organic food over conventionally produced food for nutrition reasons. According to Holly Vyner, General Manager of Biological Farmers Australia (BFA), most people buy organic food not for what it does contain, but what it doesn’t.

“The Australian Organic Market Report, commissioned by BFA, has found that the number one perceived benefit of buying organic food is that it is chemical-free, followed by additive-free, environmentally friendly, hormone- and antibiotic-free, and finally, no GMOs.”

Quoting a US study comparing organically and conventionally grown strawberries, Vyner said the organic produce outperformed the conventional in areas of taste, nutrition, colour and shelf life.

“Analysis showed that organic strawberries had significantly higher total antioxidant activity which scientists believe can cut the incidence of cancer and heart disease, as well as other debilitating diseases,” Vyner said.

While the Stanford study found that organic produce was no more nutritious than conventionally produced food, it did confirm a number of benefits of organic produce. Organic foods were found to have lower levels of pesticide residues and antibiotic-resistant bacteria, while organic milk was found to contain more omega-3 fatty acids than conventionally produced milk.

While the Stanford research team concluded that little nutritional difference exists between organic and conventional produce, Bravata said, “If you look beyond health effects, there are plenty of other reasons to buy organic instead of conventional,” such as concerns about animal welfare and the environmental effects of growing conventional produce, as well as taste preferences.