The “Glucose Eater”
Metformin: A Time-Tested Medication with Expanding Benefits
Metformin is a medication used in the management of type 2 diabetes, known for its effectiveness, safety, and long history of use. As a member of the biguanide class, metformin is prescribed to help control blood sugar levels, either alone or in combination with other medications, including insulin.[1][2][3]
Its primary actions are to:
- Decrease the amount of glucose produced by the liver,
- Reduce the absorption of glucose from the digestive tract,
- Enhance the body’s sensitivity to insulin, making it easier for cells to use glucose efficiently,[1][3]
- Enhance gut microbiome by increasing short chain fatty acids (SCFAs) such as butyrate — linked to improved gut barrier function, reduced inflammation, and better glucose metabolism,[4]
- Boost beneficial bacteria such as Akkermansia, a GLP-1 stimulator that supports prolonged satiety.[4]
Centuries-Old Medicine Rediscovered
The story of metformin begins centuries ago with the use of the plant Galega officinalis (French lilac or goat’s rue) in medieval Europe to treat symptoms of diabetes.[4][5] The plant contains guanidine compounds, which were later found to lower blood sugar. In the early 20th century, scientists began isolating and synthesizing biguanides, but early versions were too toxic for widespread use. Metformin was first synthesized in 1922, but its potential was overshadowed by the discovery of insulin. It wasn’t until the 1950s that French physician Jean Sterne conducted clinical trials demonstrating metformin’s safety and efficacy in humans.[4][5]
The drug was introduced in France in 1959 as “Glucophage,” meaning “glucose eater,” and gradually gained acceptance worldwide. After further research confirmed its cardiovascular benefits and low risk of serious side effects, metformin became the first-line therapy for type 2 diabetes and is now prescribed to over 150 million people globally.[4][5][6][7]
Expanding Uses and Mechanisms
While metformin’s main indication is type 2 diabetes, its uses have expanded. It is now also prescribed for:[7][8]
- Adjunct therapy in type 1 diabetes
- Prediabetes
- Gestational diabetes
- Polycystic ovary syndrome (PCOS)
- To counteract weight gain from certain medications
Researchers are investigating its potential to reduce cancer risk, support healthy aging, and protect against cardiovascular and neurological diseases.[7][8]
Metformin works primarily by inhibiting glucose production in the liver (gluconeogenesis), reducing intestinal glucose absorption, and improving insulin sensitivity in muscle and fat tissues. At the cellular level, it inhibits mitochondrial complex I, leading to activation of AMP-activated protein kinase (AMPK), a key regulator of energy metabolism.[1][3] This cascade not only lowers blood sugar but may also contribute to weight loss and improved cardiovascular health.[7][8]
Effective, with Few Side Effects
Metformin is generally well-tolerated, with gastrointestinal upset being the most common side effect. Rarely, it can cause lactic acidosis, especially in those with kidney problems or heavy alcohol use.[1][2] Regular monitoring of kidney function and blood sugar is recommended during treatment.
From its origins in a medieval herb to its status as a modern medical mainstay, metformin’s journey reflects ongoing innovation in diabetes care. Its proven benefits, expanding uses, and favorable safety profile have made it one of the most prescribed and studied medications in the world—a true “glucose eater” that continues to improve millions of lives.
References
- MedlinePlus. (2024). Metformin: Drug information.
- Mayo Clinic. (2025). Metformin (oral route) – Description.
- Mayo Clinic. (2017). Metformin revisited.
- Zhang, X., et al. (2022). Metformin alters the gut microbiome. npj Systems Biology and Applications.
- DrugBank. (2024). Metformin: Uses, interactions, mechanism of action.
- Hundal RS, Inzucchi SE. (2003). Metformin: new understandings, new uses. Drugs, 63(18), 1879–94.
- Texas Diabetes and Endocrinology. (2022). The history of metformin.
- Davies, M. J., et al. (2024). Metformin beyond type 2 diabetes. Diabetes, Obesity and Metabolism, 26(1), 12–24.
- Harvard Health. (2024). Is metformin a wonder drug?
Written By Brooke Lounsbury
