Dietary advice: Flash in the pan?

Obesity is the main target in the US government's latest dietary guidelines. But can this advice really make a difference? Nature's reporters sift through the heady mix of politics and science to get a taste of things to come.A healthy diet?The cover poses a question tackled on page 798 as a ‘food FAQ’. And the answer is that a Mediterranean diet based on the diet of Greece, Italy, Portugal and Spain in the 1960s was very healthy... but that the diet in those countries is less healthy now. The FAQs are part of this week's News Feature special on the science of dietary advice, starting on page 794. Other diet-related topics covered include that of who decides what food we should eat, and whether the resulting advice really makes a difference to the health problems we face today — primarily obesity. Also on the food front, the second edition of a bestseller on science and the lore of cooking is reviewed in Books and Arts, on page 802.