<SEC-DOCUMENT>0001020859-18-000006.txt : 20180103
<SEC-HEADER>0001020859-18-000006.hdr.sgml : 20180103
<ACCEPTANCE-DATETIME>20180103184642
ACCESSION NUMBER:		0001020859-18-000006
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180102
FILED AS OF DATE:		20180103
DATE AS OF CHANGE:		20180103

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			TESTA CHRISTOPHER P.
		CENTRAL INDEX KEY:			0001557425

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15723
		FILM NUMBER:		18507623

	MAIL ADDRESS:	
		STREET 1:		C/O UNITED NATURAL FOODS, INC.
		STREET 2:		313 IRON HORSE WAY
		CITY:			PROVIDENCE
		STATE:			RI
		ZIP:			02908

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_151502318839627.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-01-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001557425</rptOwnerCik>
            <rptOwnerName>TESTA CHRISTOPHER P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O UNFI</rptOwnerStreet1>
            <rptOwnerStreet2>313 IRON HORSE WAY</rptOwnerStreet2>
            <rptOwnerCity>PROVIDENCE</rptOwnerCity>
            <rptOwnerState>RI</rptOwnerState>
            <rptOwnerZipCode>02908</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, Atlantic Region</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-01-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2495</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>24.30</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14782</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-01-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4744</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>49.47</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10038</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>271</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>24.3</value>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-01-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2495</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>24.30</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2019-09-11</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2495.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The transaction price listed is a weighted average. Actual sale prices for these dispositions ranged from $49.43 to $49.54. The reporting person undertakes to provide United Natural Foods, Inc., any security holder of United Natural Foods, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote.</footnote>
        <footnote id="F2">Represents 271 shares of common stock allocated to the reporting person under the United Natural Foods, Inc. 401(k) Plan as of January 3, 2018.</footnote>
        <footnote id="F3">Closing price of United Natural Foods, Inc. on the NASDAQ National Market on the grant date.</footnote>
        <footnote id="F4">The stock options vest and become exercisable in four equal annual installments beginning on the first anniversary of the date of grant, and expire on the tenth anniversary of the date of grant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Joseph McGrail, Power-of-Attorney, in fact</signatureName>
        <signatureDate>2018-01-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
