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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0000070793-08-000011.txt : 20080227
<SEC-HEADER>0000070793-08-000011.hdr.sgml : 20080227
<ACCEPTANCE-DATETIME>20080227174904
ACCESSION NUMBER:		0000070793-08-000011
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080225
FILED AS OF DATE:		20080227
DATE AS OF CHANGE:		20080227

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NBTY INC
		CENTRAL INDEX KEY:			0000070793
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				112228617
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		90 ORVILLE DR
		CITY:			BOHEMIA
		STATE:			NY
		ZIP:			11716
		BUSINESS PHONE:		5165679500

	MAIL ADDRESS:	
		STREET 1:		90 ORVILLE DRIVE
		CITY:			BOHEMIA
		STATE:			NY
		ZIP:			11716

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NATURES BOUNTY INC
		DATE OF NAME CHANGE:	19920703

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FLAHERTY JAMES P
		CENTRAL INDEX KEY:			0001206229

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31788
		FILM NUMBER:		08647783

	BUSINESS ADDRESS:	
		STREET 1:		90 ORVILLE DRIVE
		CITY:			BOHEMIA
		STATE:			NY
		ZIP:			11716
		BUSINESS PHONE:		6315679500

	MAIL ADDRESS:	
		STREET 1:		90 ORVILLE DRIVE
		CITY:			BOHEIA
		STATE:			NY
		ZIP:			11716
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-02-25</periodOfReport>

    <issuer>
        <issuerCik>0000070793</issuerCik>
        <issuerName>NBTY INC</issuerName>
        <issuerTradingSymbol>NTY</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001206229</rptOwnerCik>
            <rptOwnerName>FLAHERTY JAMES P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NBTY, INC</rptOwnerStreet1>
            <rptOwnerStreet2>2100 SMITHTOWN AVE.</rptOwnerStreet2>
            <rptOwnerCity>RONKONKOMA</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>11779</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Vice President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>964</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options (Right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>25.5</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-02-25</value>
                <footnoteId id="F2"/>
            </transactionDate>
            <deemedExecutionDate>
                <value>2008-02-25</value>
                <footnoteId id="F2"/>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>30000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-02-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>30000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>30000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F3">10,000 options become exercisable on 2/1/2010,
10,000 options become exercisable on 2/1/2011 and
10,000 options become exercisable on 2/1/2012.</footnote>
        <footnote id="F2">Options were granted on February 1, 2008, subject to stockholder approval.  Stockholder approval was obtained on February 25, 2008.</footnote>
        <footnote id="F1">Mr. Flaherty is also the beneficial owner of 47,545 shares of NBTY, Inc. common stock through the Employee Stock Ownership Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Irene B. Fisher, Esq., pursuant to a Power of Attorney</signatureName>
        <signatureDate>2008-02-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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