NO EXERCISE NEEDED | Diabetes pill taken by millions, mimics a hard workout, scientists say

New research from the University of Miami Miller School of Medicine's Sylvester Comprehensive Cancer Centre has found that metformin, one of the most widely prescribed medications for Type 2 diabetes, appears to trigger the same weight-regulating compounds the body releases during intense physical activity.

The findings centre on a molecule called N-lactoyl-phenylalanine — known as Lac-Phe — which spikes in the bloodstream after strenuous exercise and is associated with appetite regulation, calorie burning and weight loss.

Previous studies had already linked elevated Lac-Phe levels to reduced appetite and a slimmer waistline.

What caught researchers off-guard was finding the same elevated Lac-Phe levels in patients taking metformin, even when those patients were doing no exercise at all.

The Sylvester study examined 29 patients with prostate cancer, a group that typically struggles with weight gain, elevated blood sugar and increased cardiovascular risk as a result of hormone therapy, treatment that blocks or reduces testosterone to slow cancer growth.

Researchers drew blood samples and found metformin users showed Lac-Phe levels comparable to those seen in people performing vigorous workouts, an effect that persisted even after hormone therapy began.

For oncologist Dr Marijo Bilusic, the results were hard to ignore.

"From a clinical standpoint, seeing a metabolic signal that mirrors what we associate with intense exercise was striking," he said.

"For patients whose treatments or symptoms limit physical activity, that kind of effect could be especially meaningful."

Metformin is typically prescribed for Type 2 diabetes when diet and exercise alone cannot control blood sugar levels.

The drug works by reducing glucose in the bloodstream and improving insulin sensitivity in muscle tissue without stimulating insulin secretion. The new research suggests it may be doing considerably more than previously understood.

Professor Priyamvada Rai, of the Miller School's radiation oncology department, said the findings pointed to a broader vision of cancer treatment.

"Cancer care isn't only about targeting tumours — it's also about supporting the whole patient," she said.

"By better understanding how treatments affect metabolism, we can begin to identify ways to help patients maintain strength, resilience and quality of life throughout their care."

Researchers were careful to stress the study was focused on a specific patient group and that regular exercise remains strongly encouraged during cancer treatment wherever possible.