Organic food is healthier than conventionally raised food because it contains more antioxidants, fewer toxic metals, and less pesticide residue.
This conclusion has emerged from the Newcastle study, the most comprehensive scientific analysis of organic food to date. Officially called “Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analyses” by Barański et al., the study is based on an analysis of 343 peer-reviewed studies from around the world that compare the effects of eating organic versus conventional food. Its findings were released in the respected British Journal of Nutrition on July 15, though its appearance on several other academic websites has created a flurry of interest over the past week.
The researchers found that antioxidant levels are 19 to 69 percent higher in organic produce. This can be explained in two ways. First, plants produce antioxidants to protect themselves from pests, so the more pesticides are sprayed to deter pests, the fewer antioxidants a plant has to produce on its own. Second, there is a ‘dilution effect.’ As explained by The Organic Center’s Newcastle Study Q&A, intensive fertilization drives production upward, resulting in larger, sweeter produce that contains more starch and carbohydrates, but the amount of minerals and vitamins does not increase accordingly; it stays the same, no matter the size or weight of the fruit, so healthy phytochemicals are lower in high-yield production systems.
The number of extra beneficial antioxidants that a person would consume if they switched to organic produce would be equivalent to adding 1 or 2 additional servings of conventional produce per day. This is a 20 to 40 percent increase in antioxidants without a simultaneous increase in caloric intake.
The study also found fewer toxic metals, such as cadmium, in organic produce. While cadmium levels in conventional produce are still within regulatory limits and considered safe, the researchers point out that cadmium accumulates in the body, so that consuming small amounts over a long period of time can potentially become toxic. Nor do those ‘safe’ amounts consider the cocktail of chemicals that is used on conventional produce. The Organic Center website explains that cadmium, along with mercury and lead, are the only three toxic chemicals for which the European Commission has set maximum residue levels (MRLs) in foods.
The study is criticized for coming up with a conclusion that’s different from other recent published literature on the same subject. According to The Guardian, one major study published in 2012 concluded that we “lack strong evidence that organic foods are significantly more nutritious than conventional foods, [although] eating organic food might help people avoid pesticide residues.”
Regardless of these studies’ differing outcomes, there are many excellent reasons to buy organic produce, not least of which is to support an agricultural system that is kind to the earth and concerned with long-term sustainability.
People buy organic for many reasons, ranging from health concerns and a desire to avoid chemical residues to animal welfare (although an ‘organic’ label does not mean anything when it comes to buying ethically-raised meat), taste, and care for the environment. Organic farming does not contribute to soil degradation and water pollution nearly as much as conventional agriculture, which is enough to make me want to support it. I welcome the results of the Newcastle study and hope that it encourages more consumers to seek out organic food whenever possible.