Medical associations and the World Health Organization are increasingly supporting sugar taxes as a strategy to reduce the burden of chronic diseases such as obesity. More than 100 countries introduced some form of sugar tax, in some cases alongside advertising restrictions on unhealthy foods. In Germany, a proposal by former Agriculture Minister Cem Özdemir to introduce an advertising ban on children was rejected in 2023.

Germany’s Schleswig-Holstein CDU-led state government, led by Daniel Guenther, Prime Minister of the German state of Schleswig-Holstein, plans to bring a motion to the Bundesrat on March 27, 2026, calling for a tax on sugary drinks after a similar proposal was rejected at the party’s national conference. Federal Health Minister Nina Warken is open to considering the idea, and members of the CDU, the Green Party, and the SPD signaled support, while a cross-party motion from the lawmakers is under discussion.

Public opinion appears to be supportive. A Foodwatch survey found that around 60% of respondents in Germany favored a sugar tax.

In a press briefing hosted by the Science Media Center, experts discussed the potential impact of such a policy and the measures required for its successful implementation. Karl Emmert-Fees, research associate at the Chair of Public Health and Prevention at the Technical University of Munich, Munich, Germany, highlighted findings from a 2023 modeling study that evaluated both a higher consumer tax and a manufacturer levy based on the UK model.

• This study estimated the introduction of a tax could reduce daily sugar intake from sugary drinks by approximately 2-3 g/d in the adult population.
• Over a 20-year period, this reduction could prevent about 25,000 cases of diabetes.
• The projected savings for the healthcare system were estimated at €16 billion, including €4-5 billion in treatment costs alone.

Sarah Forberger, PhD, Leibniz Institute for Prevention Research and Epidemiology, Bremen, Germany, stated, “Liquid calories are less satiating and are disproportionately popular with children and teenagers,” said Forberger. According to Statista, the per capita consumption of cola, lemonade, mixed drinks, and Fanta in Germany will reach 62 L in 2024. “That’s a lot. A properly implemented tax can reduce the sugar content in these products,” Forberger said.

However, the question of how sweeteners should be handled remains, given the limited evidence. Marc Tittgemeyer, PhD, head of the Translational Neurocircuitry research group at the Max Planck Institute for Metabolism Research in Cologne, Germany, said, “Sugar substitutes are certainly not a general solution.” For example, sucralose may be counterproductive because it signals to the brain that calories will follow, which does not happen. The brain responds by increasing the hunger signals. “As a result, people tend to eat more,” said Tittgemeyer.

The use of fructose as an alternative to glucose is associated with a higher incidence of diabetes. As Forberger emphasized, the goal should be to reduce the overall sweetness of food rather than relying on substitutes.

Sugar Tax

How effective is sugar tax? Emmert-Fees referred to a UK study that showed a sugar tax slowed the rise in obesity among young girls in England. However, this effect was not observed in boys of the same age group.

Studies from Mexico and the US showed similar findings. A study published in Science in 2024, using data from the UK Biobank, found that individuals exposed to sugar rationing in utero and early childhood were less likely to develop type 2 diabetes later in life than those not exposed.

“In Germany, 60% of the population is now overweight, and the obesity rate is between 20% and 30%. This has significant consequences for our health and our healthcare system; therefore, we urgently need to talk about prevention,” emphasized Tittgemeyer.

Excessive sugar intake alters the brain’s preference for sweetness. Highly caloric meals alter the activity of certain receptors, and sustained high sugar intake reduces receptor sensitivity over time.

“To maintain a certain level, you need more and more, which leads to shifts in tolerance and is much more pronounced with sugar than with fats or proteins,” Tittgemeyer said.

Knowledge Limits

Nutritional education remains important; however, knowledge alone is insufficient. Sugar tax proposals are often dismissed in favor of education campaigns. “That seems plausible, but it’s naive,” emphasized Tittgemeyer. Personal responsibility may apply to individuals with stable metabolic health, but it becomes less relevant when metabolic regulation is disrupted and drives an increased intake.

“Telling someone with obesity, ‘Eat less,’ is about as helpful as telling someone with clinical depression, ‘Just laugh, and you’ll feel better,’” explained Tittgemeyer. Regulatory and preventive measures are required to bring about this change.

Forberger stated that participants in intervention studies benefit from nutritional education and that knowledge plays a role. “Especially with highly processed foods, the ingredients are often barely recognizable. However, pure knowledge alone is not enough, Forberger said.

Emmert-Fees highlighted the complexity of individual responses to a sugar tax, noting that taxation alone cannot address the obesity epidemic. “But taxing sugary drinks can be an important first step.”

Policy Measures

Tittgemeyer stated that a broader societal effort is needed and that a sugar tax could contribute. “We are in a desperate situation and must start thinking about even unpleasant measures,” he said.

Emmert-Fees supported introducing a sugar tax based on the UK model, along with evaluation of its effects. He also recommended mandatory reduction targets for food products, rather than voluntary commitments.

Forberger cited Amsterdam as a model. Since the 2000s, the city has implemented a comprehensive approach that includes physical activity programs, school initiatives, living environments, and transport policies. Early data suggest that this strategy has reduced the childhood obesity rate.

Such an approach is appropriate because overweight drivers are multidimensional. A sugar tax may contribute, but it represents only one part and is not sufficient on its own to halt rising obesity rates.

All the study authors reported having no conflicts of interest.

This story was translated from Medscape’s German edition.