Metformin is said to do two paradoxical things at the same time:
- Metformin lowers insulin resistance which helps glucose to be moved from the bloodstream to the cells (The science: Reducing insulin resistance with metformin: the evidence today).
- Metformin used alone results in some weight loss (The science: 10-year follow-up of diabetes incidence and weight loss in the Diabetes Prevention Program Outcomes Study).
Here’s the paradox. If insulin is only used for pushing fat into cells then Metformin, by lowering insulin resistance should increase weight, right? What am we missing here?
One obvious answer is that insulin is the key to both pushing fat into cells as well as releasing fat from cells. Lowering insulin resistance helps take the fat from the cells and explains Metformin’s advantages. Metformin is like a key which opens the lock and allows glucose in and out of cells.
I know from my own experience that even after 5 years on the pump Metformin still helps my blood sugar levels – by roughly 20 points when taken at bedtime. Instead of waking up at 140 I wake up at 120 by taking Metformin before bed.
Metformin lowers insulin resistance. Lowering our insulin resistance both helps us take up the glucose from our blood into our cells and helps us lose weight.
Take note, I am not saying any of this to advocate for Metformin. The same study showed that Metformin can delay the onset of diabetes by as much as 10 years if given to pre-diabetics. But it is still only a delay.