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                                    GUARANTY
                                 (CO-BORROWERS)

                                                           Dated: March 29, 2001


To:         THE CIT GROUP/BUSINESS CREDIT, INC.

Address:    300 South Grand Avenue, 3rd Floor
            Los Angeles, California  90071


Gentlemen:

      Reference is made to that certain Financing Agreement dated of even date
herewith, as amended (herein the "Agreement") between you and each of the
undersigned (herein each a "Guarantor" and collectively the "Guarantors"). Each
of the Guarantors hereby unconditionally jointly and severally guarantees and
agrees to be liable for the full and indefeasible payment and performance when
due of all now existing and future Obligations (as defined in the Agreement) of
the other Guarantors. To the extent you receive payment on account of
Obligations guaranteed hereby, which payment is thereafter set aside or required
to be repaid by you in whole or in part, then, to the extent of any sum not
finally retained by you (regardless of whether such sum is recovered from you by
any Guarantor, its trustee, or any other party acting for, on behalf of or
through any Guarantor or its representative), the Guarantors' obligation to you
under this Guaranty, as amended, modified or supplemented, shall remain in full
force and effect (or be reinstated) until the Guarantors have made payment to
you therefor, which payment shall be due upon demand.

      This Guaranty is executed as an inducement to you to enter into or
continue the financing arrangement under the Agreement and to make the loans,
advances, extensions of credit or financial accommodations described therein,
and is executed in consideration of your doing or having done any of the
foregoing. Each of the Guarantors agrees that any of the foregoing shall be
deemed to have been done or extended by you in consideration of and in reliance
upon the execution of this Guaranty.

      Notice of acceptance of this Guaranty, the making of loans or advances, or
the extension of credit under the Agreement, the amendment, execution or
termination of the Agreement or any other agreements in connection therewith,
and presentment, demand, protest, notice of protest, notice of non-payment and
all other notices to


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which the Guarantors may be entitled under this Guaranty, and your reliance on
this Guaranty are hereby waived. Each of the Guarantors also waives notice of:
changes in terms or extensions of the time of payment, the taking and releasing
of collateral or guarantees (including the release of any of the Guarantors) and
the settlement, compromise or release of any Obligations, and agree that, as to
each of the Guarantors, the amount of the Obligations shall not be diminished by
any of the foregoing. Each of the Guarantors also agrees that you need not
attempt to collect any Obligations from the other Guarantors or any other
obligor or to realize upon any collateral, but may require the Guarantors to
make immediate payment of Obligations to you when due or at any time thereafter.
You shall not be liable for failure to collect Obligations or to realize upon
any collateral or security therefor, or any part thereof, or for any delay in so
doing, nor shall you be under any obligation to take any action whatsoever with
regard thereto.

      This Guaranty is absolute, unconditional and continuing, regardless of the
validity, regularity or enforceability of any of the Obligations or the fact
that a security interest or lien in any collateral or security therefor may not
be enforceable by you or may otherwise be subject to equities or defenses or
prior claims in favor of others or may be invalid or defective in any way and
for any reason, including any action, or failure to act, on your part. Payment
by the Guarantors shall be made to you at your office from time to time on
demand as Obligations become due, and one or more successive or concurrent
actions may be brought hereon against the Guarantors (or any one or more of
them) either in the same action or in separate actions. In the event any claim
or action, or action on any judgment, based on this Guaranty, is made or brought
against the Guarantors, each of the Guarantors agrees not to assert against you
any set-off or counterclaim which the other Guarantors may have, and, further,
each of the Guarantors agrees not to deduct, set-off, or seek to counterclaim
for or recoup, any amounts which are or may be owed by you to such Guarantor, or
for any loss of contribution from any other guarantor. Furthermore, in any
litigation based on the Guaranty in which you and any of the Guarantors shall be
adverse parties, the Guarantors hereby waive trial by jury and waive any claim
of laches and waive the performance of each and every condition precedent to
which the Guarantors might otherwise be entitled by law. In the event that you
bring any action or suit in any court to enforce any or all liabilities of the
Guarantors hereunder, service of process may be made on the Guarantors by
certified or registered mail, return receipt requested, at the address for
notices to the Companies (as defined in the Agreement) pursuant to the
Agreement.

      All sums at any time to the credit of the Guarantors and any property of
the Guarantors on which you at any time have a lien or security interest, or of
which you at any time have possession, shall secure payment and performance of
all Obligations


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and any and all other obligations of the Guarantors to you arising under this
Guaranty. The Guarantors shall have no right of subrogation, indemnification or
recourse to any Obligations or collateral or guarantees therefor, or to any
assets of any of the Guarantors.

      This Guaranty may be terminated as to any one of the Guarantors only as of
any Anniversary Date (as defined in the Agreement) and then only upon actual
receipt by one of your officers of at least ninety (90) days prior written
notice of termination sent by registered or certified mail; provided however,
that any of the Guarantors so terminating this Guaranty shall remain bound
hereunder, and this Guaranty shall continue in full force and effect, with
respect to any and all Obligations created or arising prior to the effective
date of such termination and with respect to any and all extensions, renewals or
modifications of said pre-existing Obligations. Termination as to any one of the
Guarantors shall not affect the obligations of any of the other Guarantors, nor
relieve the one giving such notice from liability for any post termination
collection expenses or interest. This is a continuing agreement and written
notice as above provided shall be the only means of termination, notwithstanding
the fact that for certain periods of time there may be no Obligations owing to
you under the Agreement. Guarantors acknowledge and agree that termination of
this Guaranty is an Event of Default under and as defined in the Agreement.

      Your books and records showing the loan account(s) maintained under the
Agreement shall be admissible in evidence in any action or proceeding as prima
facie proof of the items therein set forth. Your monthly statements rendered
under the Agreement shall be binding upon the Guarantors (whether or not the
Guarantors received copies thereof) and shall constitute an account stated
unless you shall have received a written statement of the exceptions thereto
within thirty (30) days after the statement was mailed by you.

      Each of the Guarantors expressly waives any and all rights of subrogation,
reimbursement, indemnity, exoneration, contribution or any other claim which it
may now or hereafter have against the other Guarantors or any other person
directly or contingently liable for the Obligations guaranteed hereunder, or
against or with respect to any Guarantors property (including, without
limitation, property collateralizing its Obligations to you), arising from the
existence or performance of this Guaranty.

      Each of the Guarantors consents and agrees that, without notice to or by
such Guarantor and without affecting or impairing in any way the obligations or
liability of such Guarantor hereunder, you may, from time to time, exercise any
right or remedy you may have with respect to the Obligations or any property
securing any or all of the Obligations or any guaranty thereof, including
without limitation, judicial foreclosure,


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nonjudicial foreclosure, exercise of a power of sale, and taking a deed,
assignment or transfer in lieu of foreclosure as to any such property, and each
Guarantor expressly waives any defense based upon the exercise of any such right
or remedy, notwithstanding the effect thereof upon any of such Guarantor's
rights, including without limitation, any destruction of Guarantor's right of
subrogation against any Borrower under the Agreement and any destruction of such
Guarantor's right of contribution or other right against any other guarantor of
any or all of the Obligations or against any other person, whether by operation
of Sections 580a, 580d or 726 of the California Code of Civil Procedure, or any
comparable provisions of the laws of any other jurisdiction, or any other
statutes or rules of law now or hereafter in effect, or otherwise. Pursuant to
Section 2856 of the California Civil Code, each Guarantor waives all rights and
defenses that such Guarantor may have because the Obligations are secured by
real property. This means, among other things: (a) you may collect from any
Guarantor without first foreclosing on any real or personal property collateral
pledged by any Borrower or any other guarantor; and (b) if you forecloses on any
real property collateral pledged by any Borrower or any other guarantor: (i) the
amount of the Obligations may be reduced only by the price for which that
collateral is sold at the foreclosure sale, even if the collateral is worth more
than the sale price; and (ii) you may collect from such Guarantor even if you,
by foreclosing on such real property collateral, has destroyed any right such
Guarantor may have to collect from any Borrower or such other guarantor. This is
an unconditional and irrevocable waiver of any rights and defenses each
Guarantor may have because the Obligations are secured by real property. These
rights and defenses include, but are not limited to, any rights or defenses
based upon Section 580a, 580b, 580d, or 726 of the California Code of Civil
Procedure.

      This Guaranty, together with the other Loan Documents (as defined in the
Agreement), embodies the whole agreement of the parties and may not be modified
except in writing, and no course of dealing between you and any of the
Guarantors shall be effective to change or modify this Guaranty. Your failure to
exercise any right hereunder shall not be construed as a waiver of the right to
exercise the same or any other right at any other time and from time to time
thereafter, and such rights shall be considered as cumulative rather than
alternative. No knowledge of any breach or other nonobservance by any of the
Guarantors of the terms and provisions of this Guaranty shall constitute a
waiver thereof, nor a waiver of any obligations to be performed by the
Guarantors hereunder.

      This Guaranty may be assigned by you and shall be for your benefit and for
the benefit of any of your assignees or transferees, and shall cover any
Obligations owed to you at the time of assignment or transfer as well as any and
all future Obligations, loans, advances or extensions of credit made under the
Agreement by such assignee


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or transferee.

      This instrument is executed and given in addition to, and not in
substitution, reduction, replacement, or satisfaction of, any other endorsements
or guarantees of the Obligations, now existing or hereafter executed by any or
all of the Guarantors or others in your favor.

      When used in this agreement, all pronouns shall, wherever applicable, be
deemed to include the singular and plural as well as the masculine, feminine,
and neuter genders. This agreement shall inure to the benefit of you, your
successors and assigns; shall be binding jointly and severally upon the
Guarantors and upon the respective heirs, executors, administrators, successors
and assigns of each of the Guarantors.

      This Guaranty may be executed in any number of counterparts, each of which
when so executed shall be deemed an original and such counterparts shall
together constitute but one and the same document.

      This Guaranty shall be governed by and construed in accordance with the
laws of the State of California.


      IN WITNESS WHEREOF the Guarantors have executed and delivered this
Guaranty effective as of the date above set forth.

TWIN LABORATORIES INC.,
a Utah corporation

By: __________________________
Title:


ADVANCED RESEARCH PRESS, INC.,
a New York corporation

By: __________________________
Title:

CHANGES INTERNATIONAL, INC.,
a Florida corporation


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By:_________________________
Title:


PR NUTRITION, INC.,
a California corporation

By:_________________________
Title:


HEALTH FACTORS INTERNATIONAL, INC.,
a Delaware corporation

By:_________________________
Title:


BRONSON LABORATORIES, INC.,
a Delaware corporation

By:_________________________
Title:


TWINLAB FSC INC.,
a Barbados corporation

By:_________________________
Title:


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