For the past several years, women have been bombarded with messages that insist breast-feeding provides babies with dramatic health advantages. And those messages have worked. More women are breast-feeding for an increasing number of months. But a new sibling-centered study reintroduces a big question: Is breast-feeding really better? And shouldn’t each individual woman decide what to do with her own body without politicians and advocates getting in her face? (Full disclosure: This newsletter is 100% formula-powered.)