Fat-burning compound shows promise in mice, but human tests are still needed
- Despite the findings, the research remains at an early stage. The experiments involved only a limited number of male mice, and TOFA has not been tested in humans. Its effectiveness, safety and appropriate dosage in people therefore remain unknown.
Scientists have tested an experimental compound that helped obese mice lose weight mainly by burning fat, while largely preserving muscle and lean tissue, without reducing how much they ate or increasing their physical activity.
The study, conducted by researchers from the University of California and published in Science Advances, found that mice given the compound known as TOFA lost an average of about 18% of their body weight over four weeks.
TOFA, or 5-tetradecyloxy-2-furoic acid, has been used in laboratory research since the 1970s. In the latest experiments, obese male mice received the compound twice a day for four weeks.
The researchers found that most of the weight loss came from fat. The animals largely maintained their muscle mass and other lean tissue. The mice also did not eat less or become more physically active, and their body temperature did not increase.
Instead, their energy expenditure rose by as much as 18%, suggesting that the compound encouraged the body to use more energy without requiring a reduction in food intake or an increase in activity.
How TOFA works
According to the researchers, TOFA appears to act through two pathways at the same time. It reduces the production of new fat while also helping cells take up and burn fat for energy.
However, the mechanism behind the overall increase in energy expenditure remains unclear. The effects extended beyond weight loss. Animals treated with TOFA showed lower blood sugar, insulin and liver-fat levels, as well as improved glucose response and reductions in some signs associated with fatty liver disease.
The researchers also tested low doses of TOFA together with semaglutide and tirzepatide, two weight-loss medicines that primarily work by reducing appetite. The combinations produced greater weight loss and improved some metabolic measures compared with the individual treatments, according to the study.
In a separate experiment, mice given TOFA maintained their lower weight for longer after treatment stopped. By comparison, mice treated with semaglutide quickly regained weight as their food intake increased.
Human testing has not yet begun
Despite the findings, the research remains at an early stage. The experiments involved only a limited number of male mice, and TOFA has not been tested in humans. Its effectiveness, safety and appropriate dosage in people therefore remain unknown.
The researchers said they plan to conduct additional toxicity and efficacy studies in larger animals before considering clinical trials in humans.
