The antioxidants in walnuts are believed to help fight oxidative damage in the body, including the damage caused by "bad" cholesterol. The British Heart Foundation explains that not all nuts are made with the same fats. BHF dietician Victoria Taylor wrote: “Brazil nuts, cashews and macadamia nuts are higher in saturated fat. Too much of this can contribute to high cholesterol levels, so eat them only occasionally. " Most nuts are high in unsaturated fat, "either polyunsaturated fat in walnuts and pine nuts, or monounsaturated fat in almonds, pistachios, walnuts and hazelnuts," Victoria said.