As a user of metformin and acarbose, I was always lead to believe that metformin use leads to a drop in folate and vitamin B12 levels, and I have been supplementing with additional folic acid and B12 to address that concern.
Then I found this paper…
It seems to hypothesise that increased carbohydrate delivery to the colon (due to action of alpha-glucosidase inhibitor) increases intestinal biosynthesis of folate. The combination of miglitol with metformin may prevent the metformin-induced fall in serum folate and vitamin B12.
What I would love to know is, is this a miglitol specific phenomenon or does it extend to acarbose as well ?
So I’m the only one who takes metformin and acarbose and supplements with extra B12 and folate ?
I was hoping maybe someone who had been on metformin long term had seen something in their blood work-up (an increase in B12 and folate levels) when they first started on acarbose.
I can’t believe that this hasn’t been seen or reported before
The article concludes: “The combination of miglitol with metformin may prevent the metformin-induced fall in serum folate and vitamin B12.”
It’s a 2000 article, only cited 20 times. I can’t find any other article backing up this claim. So it’s an interesting but very very weak assumption at this stage, unfortunately. (Remember that a third of clinical trials are fabricated…)
I’ve always had great difficulty replicating others papers, usually because they’ve left something innocuous, but important out of the methodology.
But equally I haven’t found any papers trying to replicate the study, and discrediting it.
I’m not entirely sold on the idea, but I thought it was worth raising, and I was asking if any other members had seen anything in their bloodwork to support or disprove the idea.
Very interesting info. I take B12 1000mcg 2 times a week to get my B12 in normal range, because it was low last year. The cause is metformin 500-1000 (changed it from time to time) for maybe 5-7 years. So its interesting to add acarbose, but don’t know how to understand that it helps.
Greetings
I’m 75 yo, and have used metformin for many years.
I started Acarbose 3+ months ago.
I also take a standard multi B vitamin supplement.
A recent blood test for B12 came back at 1395 pg/ml ( N 232-1245 ).
Prior B12 tests (2023, 2020) had been approx 950
So perhaps acarbose does prevent a metformin induced fall in B12, but only an N = 1
The premise actually doesn’t hold up. Generally, if you can think of a hypothesis, researchers have likely already tried testing it.
The miglitol paper you mentioned has been cited by several RCTs that specifically investigated acarbose’s effect on B12 levels. Here’s where things currently stand: long-term acarbose users show a slight, but statistically non-significant, decline in both B12 and folate levels. So combining acarbose with metformin won’t actually protect against metformin-induced B12 deficiency or high Hcy rates. In fact, one trial even showed a substantial drop in B12 levels, specifically confirming it was caused by reduced intestinal absorption.
I took metformin for decades and was not supplementing metformin with folate or B12 other than the occasional multivitamin. I never saw any effect on my folate or B12 levels. They were always in the mid- to high range. I still have a two-year supply of acarbose. I quit taking it because the excess flatulence it produced wasn’t worth it to me.
who takes metformin and acarbose and supplements with extra B12 and folate ?