EDITOR—Mann et al and Hu et al list several shortcomings in the trials reviewed by Hooper et al that explain why dietary treatments for patients with coronary heart disease were ineffective.1^–3 Inferior studies with negative results are prevalent, but where is the positive evidence that justifies the dietary recommendations?

Mann et al point to the improved outcome in the subgroup analysis of the five prolonged trials. But in that analysis Hooper et al excluded the Sydney diet-heart study, where total mortality was significantly increased, …