Research published today by members of the BHRU  (Theresa Marteau, Rachel Pechey and Ryota Nakamura) in the American Journal of Clinical Nutrition show – perhaps surprisingly – that on the whole less healthy items were no more frequently promoted than healthier ones. However, after accounting for price, price discount, and brand characteristics, the magnitude of the sales increase was larger in less healthy than in healthier food categories.

See the full published article here :

http://ajcn.nutrition.org/content/early/2015/02/11/ajcn.114.094227.full.pdf+html