It’s a fact that cows don’t produce skim milk. In order to produce skim milk, you need to take the fat out of it. For years, health authorities urged people to cut back on foods high in saturated fat, like whole milk, butter and meat, and many of them did. But now, times are changing. A new report by the Credit Suisse Research Institute shows that sales of butter in the United States rose 14 percent last year and climbed another 6 percent in the first three months of 2015. Sales of whole milk rose 11 percent in the first half of this year, while skim milk purchases fell 14 percent. The authors of the report see in these numbers a reflection of a shift away from processed foods, toward more natural foods. We now know that natural unprocessed fats are healthy, and that we need them for our health.