Abstract: Disclosed are methods of treating an individual having a condition characterized by an imbalance in type 1 and type 2 cytokine production, wherein the method comprises administering to the individual an amount of ?-hydroxy-?-methylbutyrate (HMB) effective to modulate or otherwise cause an increase in the ratio of type 1 to type 2 cytokines, including an increase in the ratio of type 1 to type 2 cytokines without a corresponding increase in type 2 cytokine levels. Also disclosed are methods of using HMB to treat asthma and allergies. The methods of the present invention are based upon the discovery that HMB modulates cytokine production, most typically by increasing type 1 cytokines without a corresponding increase in type 2 cytokines.