In their analysis of 343 peer-reviewed studies published all over the world—70% in Europe—researchers found that, on average, organic crops/crop-based foods had higher levels of antioxidants, lower concentrations of cadmium, and a lower incidence of pesticide residues.
The review found that organically grown crops had an average of 17% more antioxidants (including polyphenolics) than those produced conventionally. In their review, the researchers cited several dietary studies that suggested consuming more foods rich in antioxidants—especially fruits, vegetables and whole grains—may protect against a variety of chronic diseases including cardiovascular disease, certain cancers and neurodegenerative diseases. Antioxidants are believed to protect the body against cell damage caused by free radicals—substances in the body and in the environment (especially in smoke or pollution). When produced in the body in excessive amounts, free radicals can increase inflammation in the body and contribute to the development of disease.
Cadmium is a highly toxic metal that accumulates in the body (especially in the liver and kidneys). According to the U.S. Food and Drug Administration (FDA), cadmium is found in foods naturally and due to air pollution. Although the exact health benefits of lowering dietary intake of cadmium are unknown, the British Journal of Nutrition review found that, on average, organic crops had 48% less cadmium than non-organic crops. The researchers urge keeping cadmium levels in the diet as low as possible. They also note that the European Commission has set maximum residue levels in foods for cadmium as well as lead and mercury, also toxic metals.
Although the FDA acknowledges there are no regulatory limits for toxic elements like cadmium or lead in food, foods that are found to have higher than normal levels of such metals are brought to the attention of the Center for Food Safety and Applied Nutrition (CFSAN), who then assesses the potential hazards associated with cadmium intake at such levels.
The British Journal of Nutrition review also revealed that the frequency of occurrence of detectable pesticide residues was four times higher in conventional crops than in organic crops. According to the American Academy of Pediatrics (AAP), pesticides are chemicals intended to kill unwanted insects, plants, molds, and rodents. The AAP believes that even low-level exposure to pesticides among children is concerning, especially because "they encounter pesticides daily and have unique susceptibilities to their potential toxicity." In fact, in its policy statement on pesticide exposure in children, the AAP cites evidence associating early life exposure to pesticides with pediatric cancers, decreased cognitive function, and behavioral problems.
Even though the British Journal of Nutrition review has gotten a lot of positive press, not everyone agrees (as evidenced in this article by AG professional) that its conclusions are definitive or that such results should ultimately dictate people's perceptions or purchases when it comes to organic versus conventional food. Eating and buying food is very personal, and it's up to parents to decide what's best for their families based on personal preferences, nutrient needs, budgetary and time considerations and other factors.
In the meantime, kids should at very least be encouraged to meet current Dietary Guidelines for Americans, especially when it comes to foods that many fall short on including nutrient-rich vegetables, fruit and whole grains. Until we know more, focusing more on helping kids get closer to meeting current recommended intakes for produce and whole grains rather than pitting organic and conventional foods against one another is a great first step towards helping them meet their nutrient needs that support optimal growth and development. MyPlate recommends 1 to 2 cups fruit, 1 to 3 cups vegetables and 1.5 to 4-ounce equivalents whole grains daily, depending on your child's age and gender.
Still, if you can afford and choose to provide your family with mostly organic foods, you'll likely reap at least some benefits (eg lowering pesticide intake) by doing so.
To learn more about organic food, check out my Scoop on Food post, Should You Buy Organic Food?
Do you buy organic foods?
Image of a variety of fresh healthy foods via shutterstock.