PROVIDENCE, R.I.--(BUSINESS WIRE)--United Natural Foods, Inc. (Nasdaq: UNFI) (the "Company") today reported financial results for the fourth fiscal quarter and fiscal year ended August 1, 2015. Fiscal Year 2015 Highlights Net sales increased 20.5%, or $1.39 billion, to $8.18 billion in fiscal 2015 compared to $6.79 billion in fiscal 2014 Operating income increased 14.8% to $242.0 million in fiscal 2015 compared to $210.8 million in fiscal 2014; adjusted to exclude the effect of a $9.3 million n