Exhibit 5.1

BASS, BERRY & SIMS PLC

Attorneys at Law

A PROFESSIONAL LIMITED LIABILITY COMPANY

315 Deaderick Street, Suite 2700

Nashville, Tennessee  37238-3001

(615) 742-6200

September 10, 2009

United Natural Foods, Inc.

260 Lake Road

Dayville, CT 06241

Re:     Registration Statement on Form S-8

Ladies and Gentlemen:

We have acted as your counsel in the preparation of the Registration Statement on Form S-8 (the “Registration Statement”) relating to the United Natural Foods, Inc. 2004 Equity Incentive Plan (the “Plan”) filed by you with the Securities and Exchange Commission covering an aggregate of 1,500,000 additional shares (the “Shares”) of common stock, $0.01 par value, issuable pursuant to the Plan.

In so acting we have examined and relied upon such records, documents, and other instruments as in our judgment are necessary or appropriate in order to express the opinions hereinafter set forth and have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, and the conformity to original documents of all documents submitted to us as certified or photostatic copies.

Based on the foregoing, we are of the opinion that the Shares, when issued pursuant to and in accordance with the Plan, will be validly issued, fully paid, and non-assessable.

We hereby consent to the use of this opinion as an exhibit to the Registration Statement.

Very truly yours,

/s/ Bass, Berry & Sims PLC

www.bassberry.com