An 18 month study by Benbrook et al. 2013 (http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082429) reports on the first large-scale, nationwide study of omega fatty acids (ω) in U.S. milk produced using organic or conventional methods.  The study asserts that ω-6/ω-3 intake ratios have risen to nutritionally undesirable levels of 10 to 15 during past decades and that the optimal ratio is near 2.3. The study obtained obtained one fresh, whole-milk sample per month over 18 months from either 1-gallon or half-gallon retail containers, from 14 commercial milk processors from 7 regions throughout the U.S. They found organic milk products organic milk contained 25% less ω-6 fatty acids and 62% more ω-3 fatty acids than conventional milk, to produce a 2.5-fold higher ω-6/ω-3 ratio in conventional compared to organic milk (5.77 vs. 2.28). In addition, all individual ω-3 fatty acid concentrations considered (α-linolenic acid (by 60%), eicosapentaenoic acid (32%), and docosapentaenoic acid (19%) and conjugated linoleic acid (18%) were higher in organic than in conventional milk.