EXHIBIT 3.5

                           UNANIMOUS WRITTEN CONSENT
                         OF THE BOARD OF DIRECTORS OF
                            MANNATECH, INCORPORATED

            The undersigned, being all of the members of the Board of Directors
       (the "Board') of Mannatech, Incorporated, a Texas corporation (the
       "Corporation"), do hereby waive notice and consent that when they shall
       have signed this consent, or identical counterparts hereof, the following
       resolutions shall then be deemed to be adopted, to the same extent and
       with the same force and effect as if adopted by a unanimous vote at a
       formal meeting of the Board duly called and held for the purpose of
       acting upon the proposal to adopt such resolutions, all in accordance
       with Article 9.10(B) of the Texas Business Corporation Act:

       Amendment to Bylaws

            WHEREAS, Article IX of the Corporation's Second Amended and Restated
       Bylaws, as amended, (the "Bylaws") vests the Board with the power to
       amend certain Bylaws;

            WHEREAS, Article 11, Section 3 of the Bylaws currently requires that
       an annual meeting of shareholders be held within 13 months of the most
       recent annual meeting of shareholders; and

            WHEREAS, the Board deems it to be in the best interests of the
       Corporation to amend and restate Article 11, Section 3 of the Bylaws;

            RESOLVED, that Article II, Section 3 of the Bylaws is deleted in its
       entirety and is replaced by the following:

            "SECTION 3. ANNUAL MEETINGS.  An annual meeting of the shareholders,
            for the election of directors to succeed those whose terms expire
            and for the transaction of other business as may properly come
            before the meeting, shall be held at such place, within or without
            the State of Texas, on such date and such time as the Board of
            Directors shall fix and set forth in the notice of the meeting,
            which date shall be within 180 days subsequent to the end of the
            Corporation's most recent fiscal year."

       General Resolution

            RESOLVED, that the proper officers of the Corporation hereby are
       severally authorized and empowered to sign, execute, certify to, verify,
       acknowledge, deliver, accept, file, and accord any and all instruments,
       agreements, and documents, and to take, or cause to be taken, any and all
       actions, in the name and on behalf of the Corporation or otherwise, as
       any such officer shall, in such officer's sole discretion, deem necessary
       or desirable and in the best interest of the Corporation in order to


       effect the foregoing resolutions, and in order to carry out the purposes
       of the foregoing resolutions, and such officer's signature, or such
       actions taken by such officer, shall be conclusive evidence that such
       officer did deem same to be necessary or desirable and in the best
       interest of the Corporation in order to effect such purposes.


                           [Signature Page Follows]


     IN WITNESS WHEREOF, the undersigned do hereby execute this unanimous
     consent to be effective as of this 6th day of March 2000.


                                    /s/ CHARLES E. FIORETTI
                                    ---------------------------------
                                    Charles E. Fioretti, Director

                                    /s/ SAMUEL L. CASTER
                                    ---------------------------------
                                    Samuel L. Caster, Director

                                    /s/ ANTHONY E. CANALE
                                    ---------------------------------
                                    Anthony E. Canale, Director

                                    /s/ STEVEN A. BARKER
                                    ---------------------------------
                                    Steven A. Barker, Director

                                    /s/ CHRIS T. SULLIVAN
                                    ---------------------------------
                                    Chris T. Sullivan, Director

                                    /s/ JAMES M. DOYLE JR.
                                    ---------------------------------
                                    James M. Doyle, Jr., Director

                                    /s/ TERRY L. PERSINGER
                                    ---------------------------------
                                    Terry L. Persinger, Director