EXHIBIT 99.1

               CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
      as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

In connection with the Form 10-Q of Dean Foods Company (the "Company") for the
quarter ended March 31, 2003, as filed with the Securities and Exchange
Commission on the date hereof (the "Report"), I, Gregg Engles, Chairman of the
Board and Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C.
Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of
2002, that the Report fully complies with the requirements of Section 13(a) or
Section 15(d) of the Securities Exchange Act of 1934, as amended, and the
information contained in the Report fairly presents, in all material respects,
the financial condition and results of operations of the Company.


                                                    /s/ Gregg Engles
                                                    ---------------------------
                                                    Gregg Engles
                                                    Chairman of the Board and
                                                    Chief Executive Officer
                                                    Date: May 15, 2003


Note: This certification accompanies the Report pursuant to Section 906 of the
      Sarbanes-Oxley Act of 2002 and shall not be deemed filed, except to the
      extent required by the Sarbanes-Oxley Act of 2002, by the Company for
      purposes of Section 18 of the Securities Exchange Act of 1934, as amended.