Letters Section Editor: Robert M. Golub, MD, Senior Editor.
In Reply: Dr Mozaffarian raises 2 important issues. The first is whether changes in the dietary intake other than fat might have had counterbalancing effects on outcomes. In this article, we focused on the decreases in saturated and trans fatty acids, which corresponded to changes in low-density lipoprotein-cholesterol levels and changes in coronary heart disease outcomes. No comparable relationships with either low-density lipoprotein-cholesterol or coronary heart disease were observed in our analyses of monounsaturated fatty acid intake or in nut consumption. We are currently reanalyzing our food records to compute glycemic index and to more precisely define types of carbohydrates and grains; we plan to present these analyses in future publications. As Mozaffarian points out, post hoc analyses are confounded by adherence and other immeasurable factors, just as are the observational studies that led to the hypotheses that nut and monounsaturated fatty acid intake are related to cardiovascular disease.
Howard BV, Anderson GL, Caan B, Hsia J, Johnson K, Limacher M, Manson JE, Prentice RL, Stefanick ML, Wassertheil-Smoller S, Van Horn L, Writing Groups for the WHI Investigators FT. Low-Fat Diet and Cardiovascular Disease—Reply. JAMA. 2006;296(3):279-281. doi:10.1001/jama.296.3.280-b