Provided herein are methods of administering anti-CD3 antibodies or antigen binding fragments to a human for decreasing weight gain or increasing weight loss. In certain embodiments, the human exhibits a body mass index (BMI) or greater than or equal to about 27. In certain embodiments, the anti-CD3 antibody or antigen binding fragment does not bind or has reduced binding to at least one class of Fc (gamma) receptor.
