Effects of interventions targeting self-efficacy alone or combined with action plans were examined in the context of fruit and vegetable consumption. E-mail messages were sent to a self-efficacy group, a combined self-efficacy and action planning group and a control group. At a 6-month follow-up, 200 adults reported their fruit and vegetable consumption, along with current levels of self-efficacy and planning. The two experimental groups gained equally from the interventions, as documented by changes in behavior. In both intervention groups, change in respective cognitions predicted change in fruit and vegetable consumption. Parsimonious interventions might contribute to health behavior change.