A new research paper on the diet’s effects has whipped the nutrition field into a frenzy. Researchers behind the study say it supports keto’s health credentials; opponents claim the research shows the exact opposite. “It’s a collective mess,” says Kevin Klatt, an assistant research scientist and instructor in the Department of Nutrition Sciences and Toxicology at UC Berkeley. Overturning this hypothesis would undermine long-standing medical advice that people should keep their LDL cholesterol low, and potentially rewrite the rules on consuming fatty foods. The trial recruited 100 subjects who were otherwise healthy but had been following a ketogenic diet for at least 2 years, and who as a result had unusually high cholesterol levels in their blood.