Studies show how official dietary guidelines contribute to fatty liver disease and diabetes

• People who replace fat with refined carbohydrates while trying to lose weight have been shown to increase their risk of fatty liver disease and diabetes rather than reduce it. Nutrition and health scientist PhDr. Sven-David Müller warns against this.
• That is why, for example, Harvard researchers describe four decades of “low-fat policies” as a “failed experiment.”
• Health guidelines at the national and EU levels must take the current state of research into account more consistently. An open scientific dialogue is long overdue.

Berlin, June 17, 2026 –  Scientific analyses are casting a critical light on dietary recommendations that have been promoted for decades. According to these findings, the widespread practice of replacing fats with refined carbohydrates may increase the risk of fatty liver disease and type 2 diabetes rather than reduce it. Nutrition and health scientist PhDr. Sven-David Müller points this out. Far more important, he says, is the quality of the fats consumed and how they are replaced in daily life. While polyunsaturated fatty acids can lower cardiovascular risk, increased consumption of refined carbohydrates is considered a risk factor for metabolic diseases such as fatty liver and diabetes.

Guidelines, such as those from the German Nutrition Society (DGE) or the World Health Organization (WHO), continue to recommend limiting fat intake to 30 to 35 percent of daily energy intake. Critics, however, argue that these guidelines fail to take key scientific findings into account: For example, the DGE noted as early as 2015 that there is no established link between total fat intake and the risk of coronary heart disease.

Far more important, they say, is the quality of the fats consumed and how they are replaced in daily life. While polyunsaturated fatty acids can lower cardiovascular risk, increased consumption of refined carbohydrates is considered a risk factor for metabolic diseases such as fatty liver and diabetes. Internationally, too, the decades-long “low-fat” strategy is increasingly being viewed with skepticism. Scientists at the Harvard T.H. Chan School of Public Health have retrospectively described four decades of low-fat diets as a “failed experiment.”

“What the low-fat craze has left us with is a generation that fears fat and consumes sugar and white flour instead. We see the consequences for the liver and metabolism every day in our practice,” says PhDr. Sven-David Müller.

While some health guidelines were created with good intentions, they have failed the reality check in practice. The Forum for Evidence-Based Preventative Health (FEBPH), together with Müller, is calling for a comprehensive review of existing dietary recommendations. The goal is to align these recommendations more closely with current scientific findings and to correct misguided trends in public health communication.