<SEC-DOCUMENT>0001020859-16-000342.txt : 20160921
<SEC-HEADER>0001020859-16-000342.hdr.sgml : 20160921
<ACCEPTANCE-DATETIME>20160921163558
ACCESSION NUMBER:		0001020859-16-000342
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20160919
FILED AS OF DATE:		20160921
DATE AS OF CHANGE:		20160921

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			UNITED NATURAL FOODS INC
		CENTRAL INDEX KEY:			0001020859
		STANDARD INDUSTRIAL CLASSIFICATION:	WHOLESALE-GROCERIES & GENERAL LINE [5141]
		IRS NUMBER:				050376157
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0730

	BUSINESS ADDRESS:	
		STREET 1:		313 IRON HORSE WAY
		CITY:			PROVIDENCE
		STATE:			RI
		ZIP:			02908
		BUSINESS PHONE:		401-528-8634

	MAIL ADDRESS:	
		STREET 1:		313 IRON HORSE WAY
		CITY:			PROVIDENCE
		STATE:			RI
		ZIP:			02908

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Clark Denise M.
		CENTRAL INDEX KEY:			0001570332

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15723
		FILM NUMBER:		161895960

	MAIL ADDRESS:	
		STREET 1:		C/O UNITED NATURAL FOODS, INC.
		STREET 2:		313 IRON HORSE WAY
		CITY:			PROVIDENCE
		STATE:			RI
		ZIP:			02908
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
<TEXT>
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    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-09-19</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001020859</issuerCik>
        <issuerName>UNITED NATURAL FOODS INC</issuerName>
        <issuerTradingSymbol>UNFI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001570332</rptOwnerCik>
            <rptOwnerName>Clark Denise M.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O UNITED NATURAL FOODS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>313 IRON HORSE WAY</rptOwnerStreet2>
            <rptOwnerCity>PROVIDENCE</rptOwnerCity>
            <rptOwnerState>RI</rptOwnerState>
            <rptOwnerZipCode>02908</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8732</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>837</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
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                <transactionAcquiredDisposedCode>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock</value>
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            <conversionOrExercisePrice>
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    <footnotes>
        <footnote id="F1">Restricted stock units awarded September 19, 2014.</footnote>
        <footnote id="F2">Each restricted stock unit represents the right to receive one share of United Natural Foods, Inc. common stock upon vesting in accordance with the terms of the reporting person's restricted stock unit agreement.</footnote>
        <footnote id="F3">The restricted stock units vest as follows: one-third vested on the date of grant, and the remaining two-thirds of the award vest in two equal annual installments beginning on the first anniversary of the date of grant.</footnote>
        <footnote id="F4">The security converts to common stock on a one-for-one basis subject to the terms of the United Natural Foods, Inc. Deferred Compensation Plan.</footnote>
        <footnote id="F5">On September 19, 2016, 837 shares of United Natural Foods, Inc. (the &quot;Company&quot;) restricted stock units vested, 100% of which the reporting person had previously selected to defer to the Company's Deferred Compensation Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Lisa N'Chonon, Power-of-Attorney, in fact</signatureName>
        <signatureDate>2016-09-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
