Metformin Found to Change Blood Metal Levels in Patients

Metformin is the world’s most prescribed diabetes medication, yet experts still do not fully understand how it works. A new study from Kobe University has now shed light on this mystery. Researchers led by endocrinologist Professor Ogawa Wataru have discovered that metformin changes blood metal levels in humans, which could help explain many of the drug’s positive effects beyond lowering blood sugar.

A Closer Look at Metformin’s Unsolved Mystery

For more than 60 years, metformin has been the go-to treatment for type 2 diabetes. It not only reduces blood sugar but also shows protective benefits against cancer, inflammation, and cardiovascular disease. However, its exact mechanism of action has remained unclear, making it difficult to design improved versions of the drug.
One clue comes from the fact that people with diabetes often show altered levels of certain metals in their blood, such as copper, iron, and zinc. Prior laboratory studies indicated that metformin can bind to metals, particularly copper, and this binding ability may contribute to its effects.. Until now, however, no one had clearly shown whether metformin changes these metal levels in humans.

What Is Prosopometamorphopsia?

Prosopometamorphopsia is a rare neurological disorder in which people see faces as distorted or oddly changed. Unlike prosopagnosia (face blindness), where individuals cannot recognise faces at all, those with prosopometamorphopsia can still identify people, but the faces appear unnaturally warped.

The condition can cause facial features to appear droopy, swollen, stretched, or distorted. Sometimes only one side of the face looks distorted, while other times the whole face seems misshapen. Patients may even see their own reflection altered in mirrors.

Common symptoms include:

Drooping or misplaced eyes, nose, or mouth
Blurry or warped facial images
Hallucinations of faces morphing into scary or cartoon-like shapes
Increased distortions at night or in stressful situations

Because of these disturbing visual changes, many patients experience fear, stress, and difficulty maintaining social interactions.

The Kobe University Study

Ogawa and his team studied about 200 diabetes patients at Kobe University Hospital. Half of the participants were taking metformin, while the other half were not taking any medication.. Researchers carefully measured their blood serum for copper, iron, zinc, and other metal-related indicators.

The findings, published in BMJ Open Diabetes Research & Care, revealed the first solid evidence in humans:

Patients on metformin had lower copper and iron levels
They also showed higher zinc levels

Why These Changes Matter

Professor Ogawa highlighted the importance of this discovery, noting that such changes in metal concentrations may directly support better health outcomes. Reduced copper and iron, along with increased zinc, have been linked to improved glucose control and fewer diabetes-related complications.
This suggests that metformin’s ability to alter metal balance could be part of the reason it works so effectively. In other words, when metformin changes blood metal levels, it may be helping the body manage diabetes more efficiently.

Comparing Metformin to Newer Drugs

Japan recently approved imeglimin, a newer diabetes medication derived from metformin. Unlike its parent drug, imeglimin should not bind metals in the same way. Ogawa’s team is already comparing the two drugs to better understand how their effects differ. This comparison may reveal whether altering metal levels is a unique advantage of metformin.

Source: Inputs from various media Sources

Priya Bairagi

Copy-Writer & Content Editor

All Posts

I’m a pharmacist with a strong background in health sciences. I hold a BSc from Delhi University and a pharmacy degree from PDM University. I write articles and daily health news while interviewing doctors to bring you the latest insights. In my free time, you’ll find me at the gym or lost in a sci-fi novel.