There is little evidence to show that organic food is more nutritious than conventional food; however, eating organic food may reduce exposure to pesticides and antibiotic-resistant bacteria, according to the results of a study published in the Annals of Internal Medicine.
Organic food is food that is grown without the use of chemical pesticides and fertilizers, biotechnology, and irradiation. In contrast, conventional farming practices employ the use of chemical fertilizers, pesticides, herbicides, antibiotics, and growth hormones.
There is a commonly held perception that organic food is better or healthier than conventional food, but thus far, there is little data to confirm or refute this. Researchers from Stanford performed a comprehensive review of evidence comparing the health effects of organic and conventional foods. Their analysis included 17 studies of populations consuming organic and conventional diets and 223 studies that compared either the nutrient levels or the bacterial, fungal or pesticide contamination of various products (fruits, vegetables, grains, meats, milk, poultry, and eggs) grown organically and conventionally.
The analysis revealed little significant difference in the health effects of organic and conventional foods. There was no consistent difference in the nutrient content of organic foods versus conventional foods, except for one nutrient that was significantly higher in organic food—phosphorous. The researchers noted that this carried little clinical significance since very few people are deficient in phosphorous. The researchers found no difference in the protein or fat content between organic and conventional milk; however, a few studies indicated that organic milk might contain significantly higher levels of omega-3 fatty acids.
In terms of pesticide residue, the researchers found that organic produce had a 30 percent lower risk of pesticide contamination compared to conventional produce. Two studies compared children who consumed organic and conventional diets and found that the urine of children on organic diets had lower levels of pesticide residues. Individuals who consumed organic chicken and pork appeared to have a lower risk of exposure to antibiotic-resistant bacteria. More research is necessary to determine the clinical significance of these findings.
In short—this research appears to indicate that nutrient per nutrient, there is little difference between organic and conventional produce. However, consuming organic produce may reduce exposure to pesticides and antibiotic-resistant bacteria.
There are a variety of reasons to choose organic, including environmental factors; however, organic food is not necessarily “better”—especially if it becomes a limiting factor. It is important to consume a diet rich in fruits and vegetables, whether conventional or organic.
Smith-Spangler C, Brandeau ML, Hunger GE, et al. Are organic foods safer or healthier than conventional alternatives?: A systematic review. Annals of Internal Medicine. 2012; 157(5): 348-366.