According to an expert nutritionist Dr. Mary Enig, the anti-fat campaign began in the 1950s. It wasn't until the 1980s that it took hold of the country though. The government promoted anti-fat even when there were no scientific studies to back the claim. I doubt if the government will listen to scientific studies at this point either. Dr. Willett himself says that it will take time. He has influenced the new dietary guidelines a little. The government's dietary guidelines still strongly promote low-fat diets. But there are two tiny paragraphs at the end of the document that say that if your HDL is low, you should try a high monounsaturated fat diet and another paragraph that says that low-fat diets less than 15% fat can be dangerous. That's the extent of it. It could be years until the public catches on. I'm not holding my breath.