Dietary inflammatory index and recurrence of depressive symptoms: Results from the Whitehall II Study.

There is a growing interest in understanding the role of inflammation in diet-depression relationship. The present study examined whether the dietary inflammatory index (DII, a measure of the inflammatory potential of individuals' diets) is associated with recurrent depressive symptoms (DepS) (CES-D score>16 or taking antidepressants both at baseline and follow-up) assessed over 5 years in middle-aged men (n=3178) and women (n=1068) from the Whitehall II Study. For each increment of 1 SD of DII score, odds of recurrent DepS increased by 66% (95 % CI:1.30-2.12) in women while no significant association between DII and recurrent DepS was observed in men (OR=1.12, 95 % CI: 0.92-1.36). This association was little attenuated after adjustment for confounders and after taking into account levels of interleukin-6 and C-reactive protein. In conclusion, there is an association between pro-inflammatory diet and recurrent DepS in women which seems not be driven by circulating inflammatory markers.