Wait! I though the science was settled! The Independent reports:
Challenging any of the conventional wisdom on dietary fat has long been a form of professional suicide for nutrition experts. And saturated fats, especially, are the third rail. But Krauss persevered and concluded in 2010, after reviewing all the scientific literature, that saturated fats could not be said to cause heart disease. In March, another group of scientists, including faculty from Cambridge and Harvard, came to the same conclusion after conducting a similar “meta-analysis”. These were stunning results. It seemed that saturated fat, our principal dietary culprit for decades, had been unfairly convicted.
Yet the truth is there never has been solid evidence that these fats cause disease. We only believe this to be true because nutrition policy was derailed over the past half-century by personal ambition, bad science, politics, and bias.
Our fear of saturated fats began in the 1950s when Ancel Keys, a pathologist at the University of Minnesota, first proposed that they raised cholesterol and therefore caused heart disease. Keys was an aggressive, outsized personality with a talent for persuasion. He found a receptive audience for his “diet-heart hypothesis” among public-health experts who faced a growing emergency: heart disease, a relative rarity three decades earlier, had skyrocketed to be a leading cause of death. Keys managed to implant his idea into the American Heart Association and, in 1961, the group published the first-ever guidelines calling for Americans to cut back on saturated fats, as the best way to fight heart disease. The US government adopted this view in 1977 and the rest of the world followed. But the evidence backing these guidelines was weak. ...What the article describes is that the evidence was not just weak. It was the result of bad science, predetermined outcomes, and contradicted by the evidence from cultures that ate significant quantities of meats and fats.
Rolling over the opposition by sheer force of will was typical of Keys and his acolytes in defending their saturated-fat hypothesis. Keys was “tough and ruthless and would argue any point”, Oliver, a prominent opponent, said. Since Keys’s allies controlled so many top government health posts, critics were denied research grants and key posts on expert panels. As retribution for defending the healthiness of eggs, despite their cholesterol content, Oliver was publicly branded by two of Keys’s main allies as a “notorious type” and a “scoundrel” because “he opposed us on everything”.
In the end, Keys and his colleagues prevailed. Despite contrary observations from India to the Arctic, too much institutional energy and research money had already been spent trying to prove Keys’s hypothesis. The bias in its favour had grown so strong that the idea just started to seem like common sense.Instead, it is the low-fat, high grain diets supported by the American Heart Association that are dangerous. The article continues:
The problem, as researchers have suggested since the 1950s, is that carbohydrates are uniquely fattening. Whenever they’re eaten, the body is stimulated to release insulin, which turns out to be fantastically efficient at storing away fat. Meanwhile, fructose, the main sugar in fruit, causes the liver to generate triglycerides and other lipids in the blood that are altogether bad news. Excessive carbohydrates lead not only to obesity but also, over time, to Type 2 diabetes and, very likely, heart disease.
The best possible science from the past decade now indicates that too many carbs overall – even of the supposedly healthy, whole-grain kind – increase the risk of these diseases compared with a diet low in carbohydrates. In other words, too much whole-grain cereal for breakfast and whole-grain pasta for dinner, with fruit snacks in between, add up to a less healthy diet than one of eggs and sausage, followed by fish.We now have an obesity epidemic caused largely in part by this officious meddling. This should be a warning to those that have embraced Global Warming. In fact, this should be a cautionary tale about how science is actually made in a modern world where the government approves and funds what it considers to be the scientific "truth" and what is not.
Update (9/3/2014): From the New York Times:
People who avoid carbohydrates and eat more fat, even saturated fat, lose more body fat and have fewer cardiovascular risks than people who follow the low-fat diet that health authorities have favored for decades, a major new study shows.