Brookes had published a study whose conclusions contradicted those of Benbrook's earlier in 2012. Brookes also stated that Benbrook had made "biased and inaccurate" assumptions. More recently, in December 2013, Benbrook was the lead author of a study which reported that organic milk contained significantly higher levels of heart-healthy omega-3 fatty acids. The study was funded in part by the organic milk producer Organic Valley, although Allison Aubrey of NPR reported that they had no role in the study's design or analysis. In July 2014, Benbrook was a co-author on a meta-analysis of 343 studies examining the nutritional differences between organic and non-organic food. It concluded that organic food had higher levels of antioxidants and lower levels of cadmium, but also lower levels of protein than did conventional food. Benbrook was a signatory on a 2013 statement issued by the European Network of Scientists for Social and Environmental Responsibility which asserted that there is no consensus on the safety of genetically modified food. He has said this statement was motivated in part by I-522, a bill introduced in Washington state that year. When contacted by "Seattle Weekly", Benbrook also said that he thinks that "...technology that alters the composition of food could lead to problems beyond science’s ability to predict." He gave an address to a National Research Council study group on genetically modified foods in September 2014. In his address, he argued that the reason many people are not confident in the safety of genetically modified foods is that the regulatory systems in place rely too much on studies supplied by companies that develop such foods. Benbrook criticized a 2012 paper which concluded that organic food did not confer significant health advantages relative to conventional food. In a letter to the "Annals of Internal Medicine", he wrote that their finding of a 30 percent "risk difference" between organic and conventional food was misleading, because the metric does not refer to health risk, and that pesticide risk is a function of many other factors in addition to contamination. In 2015, Benbrook and Philip Landrigan co-authored a perspective piece in the "New England Journal of Medicine" urging the United States government to conduct new assessments of the safety of glyphosate, which had been declared a probable human carcinogen earlier that year.