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Is metformin good for your brain?

BrianTheElder

Well-Known Member
Messages
574
Location
Surrey, UK
Type of diabetes
Type 2
Treatment type
Diet only
Dislikes
Snide people
I am diabetic type 2 and take statins and metformin. I am on a strict ketogenic diet, carbs < 20g/day.
I asked Dr Jason Fung on Diet Doctor the following:
When in ketosis I may be relying on gluconeogenesis to produce glucose for my brain. If the Metformin I am taking inhibits glucose formation, might this limit the amount of energy supply to the brain and produce symptoms of fuzziness and becoming light-headed?
His reply was "It's definitely possible".
A bit worrying, as I do suffer from a fuzzy head that I normally attribute to keto flu.
Has anyone heard of this sort of problem with metformin?
 
How many Calories are you consuming a day? I ask because the Patient Information Leaflet states that you should not take them if you are following a VLCD (<1000Cal)
 
If you are not hypoglycemic there is enough glucose for your brain. Anything is possible and no doctor is going to give absolutes to a total stranger via e-mail. They could lose their license.
 
If you are not hypoglycemic there is enough glucose for your brain. Anything is possible and no doctor is going to give absolutes to a total stranger via e-mail. They could lose their license.

Og cause in that way around. But it very seldom leads to hypoglycemia
 
If you are not hypoglycemic there is enough glucose for your brain. Anything is possible and no doctor is going to give absolutes to a total stranger via e-mail. They could lose their license.
Well, he did use the word 'definitely', he had no need to.
I have seen discussions before on ketogenic diets and whether enough glucose would be produced for the brain, which apparently can't function on ketones alone. The answer was always 'but the liver will produce sufficient glucose via gluconeogenesis', hence my worry when I saw that metformin inhibits gluconeogenesis. But I have no answer to the fact that my blood does have sugar in it as shown by my meter - I will have to check more regularly.
I also think I read somewhere that hypoglycaemia is not something that occurs in ketosis, do you know about that?
 
Well, he did use the word 'definitely', he had no need to.
I have seen discussions before on ketogenic diets and whether enough glucose would be produced for the brain, which apparently can't function on ketones alone. The answer was always 'but the liver will produce sufficient glucose via gluconeogenesis', hence my worry when I saw that metformin inhibits gluconeogenesis. But I have no answer to the fact that my blood does have sugar in it as shown by my meter - I will have to check more regularly.
I also think I read somewhere that hypoglycaemia is not something that occurs in ketosis, do you know about that?

Definitely possible does not however mean definitely.. if you are really following a strict keto diet then I would suggest the pills may not be essential..however that is up to you and your doctor (who probably won't know what a ketogenic diet entails). Do you know why you are taking the statins? Have you had a cardiac event? There is a lot of debate as to whether they are beneficial. It may well be worth putting "statins" in the search box here and having a read.
What you put into your body is your choice remember.
Re the hypoglycemia there was apparently some unpublished research done in the 1970's where some subjects who were on a ketogenic diet were given insulin. Their blood sugar went down to 1.5 mol/l without ill effects. However this was deemed to be endangering their lives (although it seems it didn't) so was unpublished. That's according to Dr Stephen Finney one of the low carb gurus.
 
Definitely possible does not however mean definitely.. if you are really following a strict keto diet then I would suggest the pills may not be essential..however that is up to you and your doctor (who probably won't know what a ketogenic diet entails). Do you know why you are taking the statins? Have you had a cardiac event? There is a lot of debate as to whether they are beneficial. It may well be worth putting "statins" in the search box here and having a read.
What you put into your body is your choice remember.
Re the hypoglycemia there was apparently some unpublished research done in the 1970's where some subjects who were on a ketogenic diet were given insulin. Their blood sugar went down to 1.5 mol/l without ill effects. However this was deemed to be endangering their lives (although it seems it didn't) so was unpublished. That's according to Dr Stephen Finney one of the low carb gurus.
I have every intention of coming off both statins and metformin, that is why I have been doing a lot of research. I ask a lot of questions, but often get unhelpful answers.
My opinion is that statins reduce cholesterol, which is not good as cholesterol is actually beneficial. Also that metformin is unnecessary if I am controlling my insulin via diet.
I have a family history of heart disease, which is why the doctor put me on statins years ago, although I have no problems myself. Unfortunately, my wife insists that I don't stop either medication without speaking to my doctor; I accept she has a say in the matter. I just had a blood test so will see the doc when I have the latest results.
 
Is Fung definitely an "expert" on this subject

I know he's an expert on making $$
Such cynicism...
He is a doctor and he has stuck his neck out like so few others. He writes intelligently and I respect his opinion. He certainly knows more than me and my GP.
 
I originally submitted this post asking if anyone had heard of this sort of problem (fuzzy head) with metformin and ketosis.
No answers to that so far, so I'll take it as a no. Shame about all the nit-picking, but you get that on a lot of forums.
 
I originally submitted this post asking if anyone had heard of this sort of problem (fuzzy head) with metformin and ketosis.
No answers to that so far, so I'll take it as a no. Shame about all the nit-picking, but you get that on a lot of forums.
I came off the metformin after 3 weeks of being bound to the loo so I can't really help with that. Are you supplementing salt? The keto diet is well known for clearing out salt so it might be worth taking an extra teaspoon if you aren't. I forgot last time I did an extended fast an had a couple of dizzy turns although not fuzzy as such.
 
I have been on metformin 1500mg and now 2000mg and in ketosis as measured by a blood ketone meter for the last 8 months with no fuzzy head or other unpleasant neurological symptoms.The reason I take metformin is because I have very large liver dumps. Metformin wont stop them entirely which is why it does not cause hypoglycemia for most people but it does dampen them somewhat.
 
I came off the metformin after 3 weeks of being bound to the loo so I can't really help with that. Are you supplementing salt? The keto diet is well known for clearing out salt so it might be worth taking an extra teaspoon if you aren't. I forgot last time I did an extended fast an had a couple of dizzy turns although not fuzzy as such.
Thanks. Yes, I take half a teaspoon every morning. Perhaps I should increase that as the symptoms are keto flu-like.
 
I have been on metformin 1500mg and now 2000mg and in ketosis as measured by a blood ketone meter for the last 8 months with no fuzzy head or other unpleasant neurological symptoms.The reason I take metformin is because I have very large liver dumps. Metformin wont stop them entirely which is why it does not cause hypoglycemia for most people but it does dampen them somewhat.
Well, that's reassuring at least. So perhaps it's just keto flu after all. I am very carb sensitive, so I think it takes very little to throw me out of ketosis and this may happen accidentally. What blood ketone meter do you use, please? I use a Ketonix breath analyser, but it is not wholly satisfactory.
 
I use a freestyle neo for ketones and a contour next for glucose. Both are very expensive for strips but I have third party insurance that covers 100%. I check ketones every night before bed.
 
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