Document and Entity Information (USD $)	12 Months Ended
	Jul. 28, 2012	Sep. 06, 2012	Jan. 27, 2012
Document and Entity Information
Entity Registrant Name	UNITED NATURAL FOODS INC
Entity Central Index Key	0001020859
Document Type	10-K
Document Period End Date	Jul. 28, 2012
Amendment Flag	false
Current Fiscal Year End Date	--07-28
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 2,172,850,421
Entity Common Stock, Shares Outstanding		49,015,833
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	FY