Beta-blockers are the most frequently used drugs for the treatment of hypertension. Apart from concerns regarding potential adverse metabolic effects on lipids or insulin sensitivity, beta-blockers can also cause weight gain in some patients. This fact appears little known to clinical practitioners and trialists. Thus, only a minority of clinical trials with beta-blockers report weight changes during treatment. In trials that do report weight changes, beta-blockers are associated with a weight gain of 1.2 (range -0.4-3.5) kg. This may be attributable to the fact that beta blockade can decrease metabolic rate by 10%. Beta-blockers may also have other negative effects on energy metabolism. Obesity management in overweight hypertensive patients may therefore be more difficult in the presence of beta-blocker treatment. We therefore question the use of beta-blockers as first-line therapy for overweight or obese patients with uncomplicated hypertension.