Exhibit 10.37

FOURTH AMENDMENT TO CREDIT AGREEMENT

THIS AMENDMENT TO CREDIT AGREEMENT (this “Amendment”) is entered into as of
November 1, 2006, by and between NATURAL ALTERNATIVES INTERNATIONAL, INC., a
Delaware corporation (“Borrower”), and WELLS FARGO BANK, NATIONAL ASSOCIATION
(“Bank”).

RECITALS

WHEREAS, Borrower is currently indebted to Bank pursuant to the terms and
conditions of that certain Credit Agreement between Borrower and Bank dated as
of May 1, 2004, as amended from time to time (“Credit Agreement”).

WHEREAS, Bank and Borrower have agreed to certain changes in the terms and
conditions set forth in the Credit Agreement and have agreed to amend the Credit
Agreement to reflect said changes.

NOW, THEREFORE, for valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties hereto agree that the Credit Agreement
shall be amended as follows:

1. Section 1.1(a) is hereby amended by deleting “November 1, 2007” as the last
day on which Bank will make advances under the Line of Credit, and by
substituting for said date “November 1, 2008,” with such change to be effective
upon the execution and delivery to Bank of a promissory note dated as of
November 1, 2006 (which promissory note shall replace and be deemed the Line of
Credit Note defined in and made pursuant to the Credit Agreement) and all other
contracts, instruments and documents required by Bank to evidence such change.

2. Section 4.9(b) is hereby deleted in its entirety, and the following
substituted therefor:

“(b) Total Liabilities divided by Tangible Net Worth not greater than 1.75 to
1.0 until fiscal year end June 30, 2006 and not greater than 1.25 to 1.0
thereafter, with “Total Liabilities” defined as the aggregate of current
liabilities and non-current liabilities less subordinated debt, and with
“Tangible Net Worth” as defined above.”

3. In consideration of the changes set forth herein and as a condition to the
effectiveness hereof, immediately upon signing this Amendment Borrower shall pay
to Bank a non-refundable fee of $15,000.00.

4. Except as specifically provided herein, all terms and conditions of the
Credit Agreement remain in full force and effect, without waiver or
modification. All terms defined in the Credit Agreement shall have the same
meaning when used in this Amendment. This Amendment and the Credit Agreement
shall be read together, as one document.

5. Borrower hereby remakes all representations and warranties contained in the
Credit Agreement and reaffirms all covenants set forth therein. Borrower further
certifies that as of the date of this Amendment there exists no Event of Default
as defined in the Credit

 

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Agreement, nor any condition, act or event which with the giving of notice or
the passage of time or both would constitute any such Event of Default.

IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed
as of the day and year first written above.

 

NATURAL ALTERNATIVES INTERNATIONAL, INC.    

WELLS FARGO BANK,

    NATIONAL ASSOCIATION

By:   LOGO [g55740img01.jpg]     By:   LOGO [g55740img02.jpg] Title:   President
      Bernie Palmer                                    1/24/07         Vice
President By:   LOGO [g55740img03.jpg]       Title:   CFO         January 24,
2007      

 

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