<SEC-DOCUMENT>0001020859-18-000036.txt : 20180319
<SEC-HEADER>0001020859-18-000036.hdr.sgml : 20180319
<ACCEPTANCE-DATETIME>20180319161935
ACCESSION NUMBER:		0001020859-18-000036
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180315
FILED AS OF DATE:		20180319
DATE AS OF CHANGE:		20180319

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FUNK MICHAEL S
		CENTRAL INDEX KEY:			0001240663

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15723
		FILM NUMBER:		18698985

	MAIL ADDRESS:	
		STREET 1:		260 LAKE ROAD
		CITY:			DAYVILLE
		STATE:			CT
		ZIP:			06241

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
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_152149076167869.xml
<DESCRIPTION>FORM 4
<TEXT>
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    <periodOfReport>2018-03-15</periodOfReport>

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    <issuer>
        <issuerCik>0001020859</issuerCik>
        <issuerName>UNITED NATURAL FOODS INC</issuerName>
        <issuerTradingSymbol>UNFI</issuerTradingSymbol>
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            <rptOwnerCik>0001240663</rptOwnerCik>
            <rptOwnerName>FUNK MICHAEL S</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>
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                <value>Common Stock</value>
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            <transactionDate>
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            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>4590</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
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                <transactionAcquiredDisposedCode>
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                </transactionAcquiredDisposedCode>
            </transactionAmounts>
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                    <value>46456</value>
                </sharesOwnedFollowingTransaction>
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        </nonDerivativeTransaction>
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            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
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            <transactionCoding>
                <transactionFormType>4</transactionFormType>
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                <value>Common Stock</value>
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                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F3"/>
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            </ownershipNature>
        </nonDerivativeHolding>
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    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Unit</value>
            </securityTitle>
            <conversionOrExercisePrice>
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            <transactionDate>
                <value>2018-03-15</value>
            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
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            <transactionAmounts>
                <transactionShares>
                    <value>4590</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F5"/>
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            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4590.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>24.54</value>
                <footnoteId id="F6"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-03-15</value>
            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>5625</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>24.54</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F7"/>
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            <expirationDate>
                <value>2018-09-16</value>
            </expirationDate>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock units convert into common stock on a one-for-one basis. Accordingly, there was no purchase price paid by the reporting person.</footnote>
        <footnote id="F2">On March 15, 2018, 4,590 shares of United Natural Foods, Inc. (the &quot;Company&quot;) restricted stock units vested. The Company retained 1,710 shares on that date to satisfy certain tax withholding obligations in connection with the vesting.</footnote>
        <footnote id="F3">Represents 4,228 shares of common stock allocated to the reporting person under the United Natural Foods, Inc. 401(k) Plan's UNFI Stock Fund as of March 16, 2018.</footnote>
        <footnote id="F4">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="F5">The restricted stock units vest as follows: one-half vests on the date of grant and the remaining one-half vests on the 6 month anniversary of the date of grant.</footnote>
        <footnote id="F6">United Natural Foods, Inc.'s closing price on the NASDAQ National Market on the date of grant.</footnote>
        <footnote id="F7">The stock options vest and becomes exercisable in four equal annual installments beginning on the first anniversary of the date of grant, and expire on the tenth anniversary of the grant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Joseph McGrail, Power-of-Attorney, in fact</signatureName>
        <signatureDate>2018-03-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
