TL;DR is that I’ve found it hard to drop the last 6-7kg, even on a strict keto diet. Went to a doctor who specializes in weight management here and is a proponent of LCHF/ketogenic lifestyles. She wants to put me on Metformin 500mg.
Is there any downside to taking it? She says it will help make the stubborn last few kilos of fat easier to drop. Your thoughts?
I have mixed feelings about Metformin, and here’s why: for those without diabetes it might work against you to take it because if you do not have IR the drop in blood glucose that results from Metformin might make you hungrier. I found this to be the case for myself. I have a very long back story but I lost too much weight on keto due to having anorexia, and when I started my recovery from this disorder I had to eat high amounts of food daily, preferably processed foods, to support my weight restoration. I took 1000 mg of Metformin during this time and it in no way kept me from regaining weight. In fact I noticed it increased my appetite because my BG would drop further after taking it giving me rebound hunger. When I ceased the Metformin that hunger started to subside. Then I read about Metformin possibly damaging mitochondria, which obviously is not a desirable side effect. It might also have decreased efficacy over time. Then I have read the exact opposite of all of these anecdotes, that Metformin increases longevity and helps with weight loss. So…you could try it and see how you respond!
It might help you loose the weight… when I took it for Type 2 I spent 3 weeks almost constantly shitting
Isn’t metformin supposed to be to help control less than optimal blood sugar and not just to make it easier to lose weight? Personally I would be a bit skeptical of a dr who wants to prescribe metformin for weight loss. Are you having issues with higher than optimal blood sugar? I would try dietary changes before taking metformin (well, I wouldn’t take metformin at all for just weight loss)
I’ve had no blood sugar issues. I’m metabolically healthy.
It has 2 mechanisms of action that we know about, the first is to inhibit by 30% the amount of glucose your liver makes which is really only beneficial to type 2 diabetics who over produce glucose. I don’t think that will give any advantage to a healthy person on a high carb diet. Someone who is keto relies on their liver to feed their brain glucose … I don’t think any studies have been done to see whether metformin could make it harder for a healthy person in nutritional ketosis to make adequate glucose.
The second mechanism is to sensitive the body to insulin, that could result in lower levels and that could release more energy stored in body fat.
So I would have to say … I don’t know, and maybe.
You’re up early, mate!
Listen, my tendency is to say no to all non-essential medication. I’m on no medication at all right now and happily so. However, I’ve heard good things about Metformin, including from you, Richard, and it sounds like a relatively harmless substance with mainly upsides.
It also, however, sounds like you aren’t optimistic about it helping me break through the plateau. And, given that, I’m wondering why the doctor has prescribed it to me.
What is your fasting insulin?
If it is low, and you have no problem with glucose control, then it would have nothing to work on, right? But if it’s high, maybe? I am on the same boat, and wondering the same things (except I have more like 15kg to go)
I’m T2D - metformin was one drug a doc tried on me - gave me horrible migraines 20 minutes after taking it. Did not get better over time and actually had little effect on my blood glucose levels which surprised both me and the doc. Keto works better for me.
I have an update on this, which I mentioned in another thread I think. I did a GTT a few weeks after my OP, and my fasting insulin was 10.0. My GP in Australia agreed that Metformin was a good idea - but I still haven’t started it. Been taking 500mg of Berberine with my largest meal though… seeing no effect from that, though I’m not testing BG so who knows.
I take 1500 Metformin 3 x 500 , No side effects & just awaiting my first blood test results after taking to comeback
I’ve upped to 2 Berberine per day. Will wait on the Metformin until I speak to my doc in a week or two. A bit conservative about the idea of taking a prescription drug when I’m relatively metabolically healthy.
By the way, @richard, if you’re still on the East Coast, keto meetup? I’m sure a bunch of us are in NYC and would love to meet you! 
Gabe, I’d love to get an update on your status. I find myself in a similar situation, with a fasting insulin level of 10. Not terrible but I would like to be 5 or less. I would love to hear from other insulin resistant, non T2D people out there who take Metformin to lower insulin.
I had sudden hearing loss in one ear in December, which mostly recovered, but I immediately stopped taking Metformin and all other drugs. My doctor also advised me to stop training.
I haven’t had a fasting insulin test since, and I’ve been putting on kilos in the last few months. Just got back to the gym last weekend and back to strict keto. It’s unfortunately not a hopeful story; I certainly didn’t feel any change in weight or anythign else in the 6 weeks or 2 months I spent on Metformin.
As I understand it, Metformin does not directly lower insulin. Better blood sugar control is effected by Metformin’s action of decreasing the amount of glucose produced by the liver, and by making our skeletal muscles more responsive to the existing insulin, i.e. improving insulin sensitivity. It does make sense to me that in the long run, lower blood sugar levels will mean less insulin production for most people, but I question how much, if any. Is our body lowering insulin production in response to the average lower blood sugar level, or is it sitting there, happy with the lower blood sugar level, and in effect saying, “Okay, blood sugar is better, I’m going to keep doing what I’d doing” - secreting the same amount of insulin?
I looked at about ten websites, and what’s common is saying that “unlike many drugs for blood sugar, Metformin does not increase insulin levels, but rather increases insulin sensitivity.” I didn’t see anything saying that “Metformin lowers insulin levels.”
This study was restricted to obese nondiabetic women with Polycystic Ovary Syndrome, and the findings were that Metformin does not significantly reduce hyperinsulinemia.
Weight loss does generally lead to lower insulin levels, and Metformin is known to suppress the appetites of many people, again an indirect effect. I’m thinking that if one isn’t losing weight, then the action of Metformin to reduce insulin levels may be slight and/or take a long time.
Thanks for sharing! Best of luck getting your health back.
I was indulging in weekly carb ups for 8 straight months leading into this test so this may be confounding my results. I’ve got a retest schedule for mid May, so we will see what effect uninterrupted keto has on the number.