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Type 2 How long before Metformin changes my bs?

M

Maris Piper

Member
Messages
19
Type of diabetes
Type 2
Treatment type
Tablets (oral)
I’ve been taking 500 mg/day since 14 April and been testing my bs since March 2020 on an ad hoc basis The past couple of weeks I’ve been testing my bs before and after meals etc and I can’t see any change ( except lots of holes in my fingers!). It’s still the same as it was before starting the Metformin. I have been eating a low carb diet since March 2020. My GP told me my diabetes is either genetic or age- related ( I’m 75) I have no symptoms apart from the hba1c test (67) in April. My fasting bs is between 8 and 10 and during the day it goes up and down but by the end of the day it’s pretty similar to the fasting result regardless of how far I’ve cycled or what I’ve eaten. Advice please!
 


Metformin does a couple of things: reduces appetite, makes you a tad more sensitive to your own insulin, and tells your liver not to dump so much glucose in the morning, which would then decrease the rises you'd see in the morning. It doesn't actually do all that much to bring your blood sugars down, in all honesty. It'll make a little dent, but that's about it. It's low carb eating that would have a much, much bigger impact. And even then, it'll take a little while for your morning blood sugars to come down some, as there's a lot of glucose stored in the liver, and it'll take a little while for that to dissipate.

Blood sugars fluctuate throughout the day, responding to what you're eating and what your liver is dumping. So test before a meal and 2 hours after the first bite: you're aiming for a rise of no more than 2.0 mmol/l. And preferably, you'd stay below 8,5 all day, but I realise that for now that isn't feasable. When you say you're low carbing, what exactly does an average day's meals and drinks look like? Maybe there's some tweaking that can be done yet!

Good luck,
Jo
 
Thanks Jo. I’ve spoken to my GP who says I’m doing all that can be done in terms of diet as I am not and haven’t ever been overweight. On another thread I was told to ditch the 5 grapes I had for dessert with whole milk yogurt which I did. The only carbohydrate I have each day is porridge but my husband says that’s slow release anyway. Without it I would never get to lunchtime without feeling very wobbly and I would definitely struggle on a hilly bike ride. My GP has told me to take 2 Metformin and they will do the hba1c test again in July. I was hoping that I would see some change with Metformin but if, as you say, there won’t be one, I think I’ll give up the testing.
 
Stick with the testing, if you're willing to make a few more changes and want to see how their impact is.

Can you swap the porridge for eggs with cheese and/or bacon? Maybe some high meat content sausages tossed in for good measure? Quite filling, and won't do much of anything to your blood sugars. Porridge may be slow, but that doesn't really matter for a T2: Whether it's fast or slow, you have to process it unaided. So when it comes to uptake, it really only matters for someone who has to use insulin... They might have to split their dose to cope with the carbs, rather than take everything all at once. So that theory's out the window as well.

So, you've ditched the grapes, which is good. But you might want to add in a few strawberries, blueberries or something to spice the (I'm hoping full fat, greek?) yoghurt up? Berries are generally a low carb fruit which we can cope with, in moderation.

Keep in mind that this may be called a diet, but its goal is to keep your blood sugars under control, not lose weight, per se (though in most people with an excess of weight, it can certainly have that as an added bonus). Keep your fats and protein up, cut the carbs, and if you feel like you're losing weight you can't part with, just have a low to no carb snack. Boiled egg, cubes of cheese, some olives, that sort of thing. I'm one of those who does need to lose weight, so I mostly stick with two meals a day, preferably no snacks. But if weightloss is an issue, three meals a day with snacks in between that are solely protein and fat oriented, should keep your weight up to par.

Hope that helps,
Jo
 
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The porridge really might not be starting the day off well. What are your levels before and after it? Thought about eggs or bacon or both instead? A good 2 or 3 egg omelette with cheese cooked in butter keeps me going far longer than porridge would.

@JoKalsbeek nice to see you back!
 
Maris Piper said:
is porridge but my husband says that’s slow release anyway.
Click to expand...

As with everything related to diabetes, not everybody has the same reaction and there seem to be quite a few people who find that Porridge is bad for them. It is my daily breakfast and seems to work ok for me.

As I understand it, metformin does not increase the amount of insulin you produce, but does something that makes it work better, when means how effective it works depends on how much insulin you are producing. When I was first diagnosed, I was put on metformin and it worked very well at the start. It did take a few weeks before I started to notice the difference and a month or so before my BS dropped to acceptable levels. However after a couple of years, it stopped being effective (presumably because I was no longer producing as much insulin as before) and I was switched to insulin injections.

I presume, from the fact you are on metformin, that you have been diagnosed as Type 2, but have you been tested to make sure you are not Type 1.
 

The standard dose of Metformin is usually up to around 2g (that is 4 x 500mg tablets). Doctors often prescribe it one tablet to start, building to the higher dose if it is tolerated. Other tablet sizes are available, including slow release versions. which carry different dosage guidance.

You are just on one tablet, so it is only to be expected that the benefit you will see will be smaller than if you were on a bigger dose.

Having said that, Metformin has been researched in a number of studies. This is a link to a meta study on the drug (it is an old study, but then Metformin has been around since at least the 60s)
https://pubmed.ncbi.nlm.nih.gov/18261504/

And here is a link to an interesting study showing that Metformin, on average, depending on optimum dose, lowers the HbA1c by approx 1.1% (American units) which equates to lowering the UK measurement of HbA1c by approx 11mmol/mol. As an example, that would reduce it from 53 to 42 mmol/mol.
https://care.diabetesjournals.org/content/diacare/35/2/446.full.pdf (Feb 2012)
With evidence like this, from multiple studies, I can never understand why people dismiss Metformin as ineffective and not lowering blood glucose.
I do agree that this reduction would be much harder to see on a daily or meal by meal basis, but it is still a significant reduction, especially when compared with other T2 glucose lowering oral medications.

Consequently, Metformin certainly does have an effect on blood glucose levels (depending on dose and other factors such as average blood glucose levels), but changes in those levels will also depend on what other measures are being taken to control blood glucose:
https://www.diabetes.co.uk/insulin/diabetes-and-metformin.html

Regarding your porridge - it doesn't really matter if the carbs are labelled fast or slow, or whether it fills you up until lunch. The real question is what it does to your blood glucose, and how well your body tolerates the portion size you have.

Edited for clarity
 
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Brunneria said:
HbA1c by approx 1.1% (American units) which equates to lowering the UK measurement of HbA1c by approx 11mmol/mol. As an example, that would reduce it from 53 to 48 mmol/mol.
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Wouldn’t that be 42 not 48?

That’s a lot bigger reduction than I thought it was. Off to read your links.
 
Thanks for all your replies.My bs 90 mins after porridge is either up 1 on my fasting level or has actually gone down depending what I do after breakfast. Last week for instance my fasting level on one day was 9.2. I had breakfast and an hour later went for a bike ride and tested when I got back and it was 6.3. Another day it was 8.5 on waking and 7.2 after breakfast and I didn’t do any “exercise” . However another day it was 9.1 on waking and 10 after breakfast. Frankly I can’t make any sense of it!
 
HSSS said:
Wouldn’t that be 42 not 48?

That’s a lot bigger reduction than I thought it was. Off to read your links.
Click to expand...

Yes. Should have been 42. Thank you. Will edit. My fingers are creating more typos than type today.!
 
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Well it’s not exactly testing the porridge if you include a bike ride so I’d discount that reading as informative about the porridge. That drop is likely about the bike ride.

To test it I’d test immediately before eating (a separate test to waking if there’s any delay. I often change a fair bit in the hour after getting up before eating) then again after 2 hrs. And in those two hours do no exercise, just normal pottering around type stuff.

For some people their waking reading is high due to dawn phenomenon but will drop once they start moving about. Others will continue to rise for several hours until they eat. You need to know what’s normal for you independent of food really to separate the potential triggers ie DP, the food and exercise.

another approach would be to have porridge for lunch a couple of times and test either side of that so the morning effect is removed from the equation. (Though our ability to cope with carbs tends to improve throughout the day for many of us so lunch and even more so dinner would give better results than breakfast)

of course you might be lucky enough that your chosen quantity of carbs in porridge is within your tolerance level. But as your levels seem a bit high I think this is worth exploring.
 
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