Dietary compositions and methods employ a mammal food base and a component comprising estrogen, androgen or a mixture thereof in an amount sufficient to reduce weight gain normally incurred in the mammal type subsequent to neutering, castration, spaying, ovariectomy or ovariohysterectomy, or post menopause. Preferably, the component comprises phytoestrogen, phytoandrogen or a mixture thereof. The compositions are adapted for administration to the mammal on a regular, preferably daily, basis.
