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                                                                   EXHIBIT 10.21




                  THE SECURITIES EVIDENCED HEREBY HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE OR
OTHER SECURITIES LAWS. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION
HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR
OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS THE
TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF
THE SECURITIES ACT.

No. 01                                                           60,246 Warrants


                               WARRANT CERTIFICATE

                            WEIGHTWATCHERS.COM, INC.


                  THIS CERTIFIES THAT, Weight Watchers International, Inc., a
Virginia corporation ("WWI"), is the owner of 60,246 Warrants (the "WARRANTS")
as described above, transferable only on the books of WeightWatchers.com, Inc.,
a Delaware corporation (the "COMPANY"), by the holder thereof in person or by
his or her duly authorized attorney, on surrender of the Certificate properly
endorsed. Each Warrant entitles the holder thereof (the "HOLDER"), at its option
and subject to the provisions contained herein and in the Warrant Agreement,
dated as of November 24, 1999 (the "WARRANT AGREEMENT"), between the Company and
WWI, to purchase from the Company, one Warrant Share per Warrant at the exercise
price per share of $500.00 (the "EXERCISE PRICE"), or by Cashless Exercise. This
Warrant is subject to the terms and provisions contained in the Warrant
Agreement, to all of which terms and provisions the Holder of this Warrant
Certificate consents by acceptance hereof. The Warrant Agreement is hereby
incorporated herein by reference and made a part hereof. Reference is hereby
made to the Warrant Agreement for a full statement of the respective rights,
limitations of rights, duties and obligations of the Company and the Holders of
the Warrants. Capitalized terms used but not defined herein shall have the
meanings ascribed thereto in the Warrant Agreement. This Warrant Certificate
shall terminate and become void as of 5:00 p.m. on November 24, 2009 (the
"EXPIRATION DATE") or upon the exercise hereof as to all the shares of Common
Stock subject hereto. The Exercise Price and the number of Warrant Shares
purchasable upon exercise of the Warrants shall be subject to adjustment from
time to time as set forth in the Warrant Agreement.

                  Reference is hereby made to the further provisions of this
Warrant Certificate set forth on the reverse hereof and such further provisions
shall for all purposes have the same effect as though fully set forth at this
place.


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                  THIS WARRANT CERTIFICATE SHALL BE GOVERNED BY, AND CONSTRUED
AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

                  IN WITNESS WHEREOF, the Company has caused this Warrant
Certificate to be executed on behalf of the Company on the date set forth below.

Dated: November 24, 1999


                                            WEIGHTWATCHERS.COM, INC.



                                        By:  /s/ Philippe Amouyal
                                             ----------------------------------
                                             Name:
                                             Title:




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                    [FORM OF REVERSE OF WARRANT CERTIFICATE]



                  This Warrant Certificate is issued under and in accordance
with the Warrant Agreement. A copy of the Warrant Agreement may be obtained for
inspection by the Holder hereof upon written request to the Company c/o The
Invus Group, Ltd., 135 East 57th Street, New York, New York 10022.

                  Warrants may be exercised at any time until 5:00 p.m., New
York City time on the Expiration Date. Subject to the terms of the Warrant
Agreement, the Warrants may be exercised in whole or in part by surrender of
this Warrant Certificate with the form of election to purchase Warrant Shares
attached hereto duly executed and with the simultaneous payment of the Exercise
Price (i) in cash to the Company at the office of the Company or (ii) by
Cashless Exercise. Payment of the Exercise Price in cash shall be made in cash
or by certified or official bank check payable to the order of the Company or by
wire transfer of same-day funds to an account designated by the Company for such
purpose. Payment by Cashless Exercise shall be made by the surrender of a
Warrant or Warrants represented by one or more Warrant Certificates and without
payment of the Exercise Price in cash, in exchange for the issuance of such
number of shares of Common Stock equal to the product of (1) the number of
shares of Common Stock for which such Warrants would otherwise then be nominally
exercised if payment of the Exercise Price were being made in cash and (2) the
Cashless Exercise Ratio.

                  The Warrant Agreement provides that upon the occurrence of
certain events the number of shares of Common Stock issuable upon the exercise
of each Warrant shall, subject to certain conditions, be adjusted.

                  In the event the Company enters into a Combination following
which this Warrant remains outstanding, the Holder hereof will be entitled to
receive upon exercise of the Warrants the shares of capital stock or other
securities or other property of such surviving entity as such Holder would have
been entitled to receive upon or as the result of such Combination had the
Holder exercised its Warrants immediately prior to such Combination; PROVIDED,
HOWEVER, that in the event that, in connection with such Combination,
consideration to holders of shares of Common Stock in exchange for their shares
is payable solely in cash or in the event of the dissolution, liquidation or
winding-up of the Company, the Holder hereof will be entitled to receive
distributions on an equal basis with the holders of shares of Common Stock or
other securities issuable upon exercise of the Warrants, as if the Warrants had
been exercised immediately prior to such events, less the Exercise Price.

                  The Company may require payment of a sum sufficient to pay all
taxes, assessments or other governmental charges in connection with the transfer
or exchange of the Warrant Certificates pursuant to Section 3.6 of the Warrant
Agreement but not for any exchange or original issuance (not involving a
transfer) with respect to the exercise of the Warrants or the Warrant Shares.



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                  Upon any partial exercise of the Warrants, there shall be
issued to the Holder hereof a new Warrant Certificate in respect of the Warrant
Shares as to which the Warrants shall not have been exercised. This Warrant
Certificate may be exchanged at the office of the Company by presenting this
Warrant Certificate properly endorsed with a request to exchange this Warrant
Certificate for other Warrant Certificates evidencing an equal number of
Warrants. In the event any fractional Warrant Shares would have to be issued
upon the exercise of the Warrants, the Company may, at its option, pay an amount
in cash equal to the Current Market Value for one Warrant Share on the Business
Day immediately preceding the date the Warrant is exercised, multiplied by such
fraction, in lieu of issuing such fractional share.

                  The Warrants do not entitle any holder hereof to any of the
rights of a stockholder of the Company. All shares of Common Stock issuable by
the Company upon the exercise of the Warrants shall, upon such issue, be duly
and validly issued and fully paid and non-assessable.

                  The Holder of this Warrant Certificate may be deemed and
treated by the Company as the absolute owner of the Warrant Certificate for all
purposes whatsoever and the Company shall not be affected by notice to the
contrary.



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                   FORM OF ELECTION TO PURCHASE WARRANT SHARES
                 (to be executed only upon exercise of Warrants)

                                    [         ]


                  The undersigned hereby irrevocably elects to exercise
____________ Warrants at an exercise price per Warrant Share of $________ to
acquire an equal number of Warrant Shares on the terms and conditions specified
in the within Warrant Certificate and the Warrant Agreement therein referred to,
surrenders this Warrant Certificate and all right, title and interest therein to
WeightWatchers.com, Inc., and directs that the shares of Common Stock
deliverable upon the exercise of such Warrants be registered or placed in the
name and at the address specified below and delivered thereto.

Date:  ________________, ____


                                         _______________________________1/
                                         (Signature of Owner)


                                         -------------------------------
                                         (Street Address)


                                         -------------------------------
                                         (City)    (State)    (Zip Code)



--------
1/       The signature must correspond with the name as written upon the face of
         the within Warrant Certificate in every particular, without alteration
         or enlargement or any change whatever.


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Securities and/or check to be issued to:

         Please insert social security or identifying number:

         Name:

         Street Address:

         City, State and Zip Code:

Any unexercised Warrants evidenced by the within Warrant Certificate to be
issued to:

         Please insert social security or identifying number:

         Name:

         Street Address:

         City, State and Zip Code: