Aspartame linked to brain and heart changes in long-term mouse study
A new study has found that aspartame, a common artificial sweetener, may cause lasting changes to brain energy use and heart function in mice. Researchers at the Ramazzini Institute in Bologna, Italy, discovered these effects even at doses well below current safety limits. The findings raise questions about the long-term impact of aspartame consumption on metabolic and cognitive health.
The year-long study tracked mice given low doses of aspartame. After two months, their brains showed increased glucose uptake, suggesting an initial spike in energy demand. But by ten months, glucose use had dropped, indicating a shift in how the brain processes fuel.
The research also revealed higher lactate levels in the brain, a sign of inefficient energy production and potential stress on neurons. Over time, the mice struggled with memory and learning tasks. By eight months, they took longer to find an escape hole in behavioural tests, showing clear cognitive decline. The hearts of aspartame-treated mice also showed signs of strain. Mild thickening of the heart muscle, known as cardiac hypertrophy, reduced pumping efficiency. This weakened the oxygen supply to organs, including the brain, adding to the metabolic stress observed.
The study suggests that even low, long-term aspartame intake could alter how the brain and heart manage energy in mice. These changes included reduced glucose processing, higher neuronal stress, and impaired heart function. The results highlight the need for further research into the sweetener’s effects on human health over extended periods.
