Specifically, the researchers said that organic fruits, vegetables and cereals contain significantly higher concentrations of antioxidants than conventionally grown crops. They added that organic produce and cereals were found to have lower levels of toxic metals and pesticides.
For the study -- said to be the largest of its kind -- the researchers analyzed more than 340 international, peer-reviewed studies that looked at compositional differences between organic and conventional crops.
According to the paper, researchers found that organically grown produce and cereals have between 19 and 69 percent higher concentrations of certain antioxidant compounds than conventionally grown crops.
"Many of these [antioxidant] compounds have previously been linked to a reduced risk of chronic diseases, including [cardiovascular] and neurodegenerative diseases and certain cancers, in dietary intervention and epidemiological studies," the paper reads.
The researchers added that pesticide residues were four times more likely to be found in conventional crops than organic ones. Organic produce and cereals were also found to have significantly lower concentrations of cadmium, a toxic heavy metal.
"This study demonstrates that choosing food produced according to organic standards can lead to increased intake of nutritionally desirable antioxidants and reduced exposure to toxic heavy metals," lead study author Carlo Leifert said, per a news release. "This constitutes an important addition to the information currently available to consumers which until now has been confusing and in many cases is conflicting."
The question of whether or not organic food is really better nutritionally has plagued health-conscious foodies for years; but despite Leifert's confidence, it doesn't seem that his new study will put this debate to rest.
When it comes to antioxidants, for example, the jury is still out as to whether the compounds really have a substantial impact on health. In addition, as The Guardian notes, "the higher levels of cadmium and pesticides in the conventional produce [referenced in the study] were still well below regulatory limits."
The BBC also pointed out that levels of proteins and amino acids "were lower in the organic crops sampled" in the study.
"You are not going to be better nourished if you eat organic food," Tom Sanders, a professor of nutrition at King's College London, told The Guardian this week. "What is most important is what you eat, not whether it's organic or conventional. It's whether you eat fruit and vegetables at all. People are buying into a lifestyle system. They get an assurance it is not being grown with chemicals and is not grown by big business."
A number of earlier studies that have looked at the differences between organic and conventional crops seem to support Sanders' comments.
In 2012, for instance, a large study conducted by Stanford researchers found that organic foods are, on average, "no more nutritious" than conventional ones, per The New York Times. A 2009 study published in the American Journal of Clinical Nutrition similarly concluded that there's "no evidence of a difference in nutrient quality between organically and conventionally produced foodstuffs."
But there are also studies that seem to support the idea that organic crops are indeed better for health. A 2010 study by Washington State University researchers found evidence that organic strawberries contained more vitamin C than conventional ones.
In addition, there is some scientific evidence to support the idea that consuming pesticides could be harmful to health.
Ultimately, it seems that more research still needs to be conducted to determine conclusively whether or not organic produce is really better for health.
Leifert himself acknowledges that his team's study should only be used as a "starting point" and that more research needs to be done into the possible health benefits of organic food.
"We have shown without doubt there are composition differences between organic and conventional crops, now there is an urgent need to carry out well-controlled human dietary intervention and cohort studies specifically designed to identify and quantify the health impacts of switching to organic food,” he said, per a press release.
Leifert's study, which was peer-reviewed, was published Friday in the British Journal of Nutrition. Read it here.