Research into health benefits of organics to be taken with a pinch of salt - Aussie scientist

At a time of increasing food insecurity, “it would be lovely if we could all eat organic”,​ but the problem is it cannot feed us all, said Joanna McMillan, a practising nutritionist, researcher, author and founder of Dr Joanna.

Talking about nutrition now means nothing if we can’t take into account how we are going feed ourselves in 2050, when the world will have to feed 2bn more people than today.

“Then the discussion is void. Even if something is good for human health, is it also going to feed everyone? There is evidence that organic farming takes more land and water; these are things that may not have been well researched​,” she said.

Moreover, the question as to whether organic food is better for humans has not been well studied. The problem lies in the inherent difficulties in devising a study that will be reliable, she says.

A good example of this was a major population-based 2018 study of nearly 69,000 French adults that found a significant reduction in the risk of cancer among people who ate a large amount of organic food.

Taken at face value, the research promotes organic food consumption as a promising preventive strategy against cancer. Yet the findings should be taken with a grain of salt, as the intake levels were self-reported and not validated.

“We have to take care to read beyond the headline to really understand what the results tell us​,” said McMillan.

Notably, the participants who reported consuming more organic produce had better diets overall. They ate more fruit, vegetables, nuts and legumes, while eating less processed meat, other meat, poultry and milk.

“It is therefore very difficult to tease apart whether their lower risk of cancer came from choosing organic produce and what was simply a reflection of a higher intake of plant foods overall. Were these responsible for the effect​?,” she said.

“Those with a higher organic food intake were also more likely to have a higher income, higher occupational status and have reached a higher education level. This may also impact other lifestyle factors known to relate to cancer risk​.”

Although that study tried to account for such confounding factors, it is still not easy to tease them apart. Nevertheless the association between organic food intake and risk of cancer was found to be significant, and that should be enough to warrant further research.

As to whether the non-synthetic pesticides and fertilisers used in organic food production might intuitively lead to healthier crops, it might “seem like a logical gut reaction​,” said McMillan. “But with my technical hat on, the research is not all that compelling​.”

She said: “When you look at these chemicals, we know they can be carcinogenic, what we don​’t know is if the trace levels, and different countries have different thresholds of what is allowed and they are policed differently​.

“It​’s a very grey area. There​’ no doubt it would be wonderful if we could reduce or not have any chemicals at all in our food production, but I think we have to be practical. We have to produce enough food anyway​.”

While science finds ways to better research the health benefits of organic foods, consumers should simply focus on their own diets. The simple fact is that Australian are not eating enough of the right stuff and going through too much processed meat and nutritionally questionable convenience food.

For those who have cut these out while eating enough whole grains, fruits and vegetables, and exercising every day, eating organic might show health benefits and lower their cancer risk.

“But I expect that this risk reduction is very small compared to if we could get people around the world just following the basic advice of eating more whole plant foods, whether they are organic or not​,” McMillan added.