In Reply: Dr Plotnikoff alludes to the importance of the baseline omega-3/omega-6 ratio and vitamin D status as potential confounders. We do not believe these are plausible explanations for the negative findings. First, we are unaware of any clinical data showing that these factors substantially influence pathological immune responses in patients with Crohn disease. Second, although we did not measure either vitamin D concentrations or the omega-3/omega-6 ratio at baseline, the EPIC trials had relatively large sample sizes; thus, both known and unknown confounders would likely have been equally distributed in the 2 treatment groups.
Feagan BG. Fatty Acid and Vitamin D Status in the EPIC Trials of Crohn Disease Treatment—Reply. JAMA. 2008;300(6):650. doi:10.1001/jama.300.6.650-b