Research

Energy balance

Metformin lowers blood glucose primarily by inhibiting mitochondrial complex I in the liver, which reduces ATP production and suppresses gluconeogenesis, rather than through direct activation of AMPK.

Metformin works by slowing down your liver's production of glucose. It does this by mildly affecting the energy factories (mitochondria) in liver cells, which signals the liver to stop making sugar when it doesn't need to. This is why it lowers blood sugar without causing dangerous lows (hypoglycemia) on its own.

GoodQualifiesHIGH confidence
The most widely accepted model of the anti-hyperglycaemic action of metformin is that suppression of hepatic gluconeogenesis occurs principally as a consequence of mitochondrial inhibition... the most recent mouse genetic studies indicate that suppression of gluconeogenesis may depend more directly on the mitochondrial respiration rate... and/or on AMPK-independent cellular responses to reductions in ATP availability
Graham Rena et al. · Diabetologia · 2013

Why this rating

Based on a comprehensive review of genetic knockout studies and biochemical assays.

Source

Molecular mechanism of action of metformin: old or new insights?

Graham Rena et al. · Diabetologia · 2013

DOI 10.1007/s00125-013-2991-0

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DOI resolved against Crossref · corpus check 2026-06-10

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