# Is metformin 2-4x more effective at lowering A1C than regular exercise? **URL:** \ **Category:** Factual Questions\ **Created:** [April 23, 2016, 4:22pm UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910 "2016-04-23T16:22:14Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [April 23, 2016, 4:22pm UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/1 "2016-04-23T16:22:14Z")
> **[Metformin - Some Background Information - Diabetesnet.com](https://www.diabetesnet.com/about-diabetes/diabetes-medications/metformin/)** > > Metformin was eventually found to be 20 times less likely to cause lactic acidosis, but it was tainted by the history of its phenformin. > [@](#): > > [Metformin] Lowers HbA1c by 1.5% to 2.0% > **[Study: The Best Exercise for Diabetes](https://time.com/archive/6932179/study-the-best-exercise-for-diabetes/)** > > It's no secret that exercise is key to controlling type 2 diabetes — and many doctors already urge their diabetic patients to get active. But... > [@](#): > > Overall, researchers saw improvements in blood-sugar control in all the patients who worked out. Compared with controls, patients in the aerobic group had a reduction of .51% in their hemoglobin A1C values — a test that measures blood-sugar control over the previous two to three months (lower is better). The weight-training group had a .38% reduction compared with controls. But the combined exercise group showed further improvements: in those patients, the A1C values went down an additional .46% over the aerobic group, and .59% over the weight-training group. Compared to controls, the combo exercisers had a nearly 1% lower A1C reading. > **[Exercise and HbA1c - DSM](https://www.diabetesselfmanagement.com/blog/exercise-and-hba1c/)** > > A review finds that structured exercise programs can significantly lower HbA1c in people with Type 2 diabetes. Should health insurance cover them? > [@](#): > > Over the years, different studies have explored the potential benefits of a wide variety of exercise programs in people with Type 2 diabetes. The authors of a clinical review published last week attempted to distill the results of these studies. Published in the Journal of the American Medical Association, the review examined 47 clinical trials from 1980 to the present. Of these 47 studies, 23 measured the impact of assigning participants to a structured exercise program; the other 24 tested the effect of giving out exercise advice (often in combination with other advice). Each study lasted at least 12 weeks. Overall, structured exercise programs won out over exercise advice, with an average HbA1c reduction of 0.67% compared with the control group in each study; exercise advice saw an average drop of 0.43% compared with each control group. > > Within structured exercise programs, aerobic exercise programs had the best result, with an average HbA1c reduction of 0.73% compared with control groups; resistance programs saw a 0.57% drop, while programs that combined both cardio and resistance saw only a 0.51% drop. Among all structured exercise programs, those that demanded more than 150 minutes of exercise each week were associated with a 0.89% drop in HbA1c; those that demanded 150 minutes or less led to a 0.36% drop. In the separate category of exercise advice, only exercise advice combined with dietary advice was found to reduce HbA1c, with an average reduction of 0.58%; exercise advice alone had no net effect, leading to the overall 0.43% HbA1c drop associated with exercise advice. I guess that is just surprising, exercise is treated as the de facto treatment for type 2 diabetes (along with changes in diet) but the research I’m seeing shows that exercise is about 4x less effective than the first class of meds prescribed for diabetics. I’ve heard stories of people getting their diabetes under control with lifestyle changes, is there more to it? Is it more diet than exercise that gets blood sugar under control? How do these stories I’ve heard of people getting their diabetes under control via diet and exercise work if exercise (one of the 2 components of diet & exercise) is far less effective than medication? Not asking for personal advice, I’m just curious. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 23, 2016, 4:52pm UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/2 "2016-04-23T16:52:55Z")
It’s because it’s easier to comply with metformin (take a pill once or twice a day) than with exercise (10,000 steps a day/20 minutes of aerobic exercise). Better results are seen with metformin because more people are taking metformin as prescribed than taking exercise as prescribed. ---
**Author:** ![pohjonen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pohjonen/32/423_2.png) [@pohjonen](https://boards.straightdope.com/u/pohjonen)\ **Post date:** [April 23, 2016, 7:31pm UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/3 "2016-04-23T19:31:00Z")
That’s a good thing. I could never safely get more than 6 feet from the bathroom on metformin which made any form of exercising difficult. I guess I could have done free weights while sitting on the commode. ---
**Author:** ![GusNSpot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gusnspot/32/436_2.png) [@GusNSpot](https://boards.straightdope.com/u/GusNSpot)\ **Post date:** [April 23, 2016, 8:04pm UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/4 "2016-04-23T20:04:03Z")
Also, it seems this is about people with Type 2 and no other issues. Those of us with actual physical problems, which reduce the amount of exercise of the needed type and amount of exertion much more difficult toi attain. Arthritis, prostheses, etc… etc… ---
**Author:** ![Bumbazine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bumbazine/32/362_2.png) [@Bumbazine](https://boards.straightdope.com/u/Bumbazine)\ **Post date:** [April 24, 2016, 10:04pm UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/5 "2016-04-24T22:04:06Z")
**pohjonen** , there is an extended release form of metformin called, surprising enough, ‘metformin ER’, which many people don’t get diarrhea from, but it is outrageously expensive. Still, if you have better insurance than I, you might ask your doctor about it. ---
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [April 25, 2016, 12:05am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/6 "2016-04-25T00:05:26Z")
[Pharmacychecker.com](http://Pharmacychecker.com) has 1000mg Metformin XR from Canadian pharmacies starting at $0.18 a pill. I have no idea what it costs in the US. ---
**Author:** ![aldiboronti](https://avatars.discourse-cdn.com/v4/letter/a/9fc348/32.png) [@aldiboronti](https://boards.straightdope.com/u/aldiboronti)\ **Post date:** [April 25, 2016, 12:19am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/7 "2016-04-25T00:19:37Z")
I’ve taken metformin ER for the last couple of years for diabetes type 2 with no side effects at all. Fortunately as I’m English and over 65 it’s free on the NHS. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [April 25, 2016, 12:46am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/8 "2016-04-25T00:46:52Z")
> [@Bumbazine](#): > > **pohjonen** , there is an extended release form of metformin called, surprising enough, ‘metformin ER’, which many people don’t get diarrhea from, but it is outrageously expensive. > Still, if you have better insurance than I, you might ask your doctor about it. The generic (glucophage ER, for Metformin XR) is on Walmart’s $4 list (for 500mg, 60 day supply) ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [April 25, 2016, 1:00am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/9 "2016-04-25T01:00:58Z")
First thing I should do is explain those percentages. A .5% reduction doesn’t sound significant, but it is. A1C measures what percentage of blood hemoglobin is glycosolated, that is locked in a hemoglobin-glucose complex. So a .5% reduction means a reduction from 7% to 6.5% which is significant. And a reduction from 7% to 5.5% even more so. When I was first diagnosed, my A1C was about 8% and, after a year of using metformin, with no change in the amount of exercise I got, dropped to about 6.5%, consistent with the study reported in the OP. But metformin has an interesting side effect. I lost about 20 lb over the next two years with no changa1e in exercise or diet. A couple years after that, I started on diet and lost another 40 lb and my A1c dropped to 5.5% and stayed there. And I get less regular exercise than I did then. When my doctor started me on metformin, he advised me to start with one 500 mg pill every other day and then, after my bowels stabilized, to take one a day for a few days and go onto the regular dose of two pills a day. I never had the least problem. YMMV. ---
**Author:** ![Mean\_Mr.Mustard](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mean_mr.mustard/32/3865_2.png) [@Mean\_Mr.Mustard](https://boards.straightdope.com/u/Mean_Mr.Mustard)\ **Post date:** [April 25, 2016, 1:23am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/10 "2016-04-25T01:23:46Z")
For those suffering from GI issues from Metformin, if you can ride it out for a few days the diarrhea often goes away. The trick is in the riding out. mmm ---
**Author:** ![pohjonen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pohjonen/32/423_2.png) [@pohjonen](https://boards.straightdope.com/u/pohjonen)\ **Post date:** [April 25, 2016, 2:42am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/11 "2016-04-25T02:42:54Z")
> [@Mean\_Mr.Mustard](#): > > For those suffering from GI issues from Metformin, if you can ride it out for a few days the diarrhea often goes away. > > The trick is in the riding out. > mmm I gave it six months. That’s a whole shitload of diarrhea. (ha) ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [April 25, 2016, 3:46am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/12 "2016-04-25T03:46:30Z")
> [@Wesley\_Clark](#): > > I guess that is just surprising, exercise is treated as the de facto treatment for type 2 diabetes (along with changes in diet) but the research I’m seeing shows that exercise is about 4x less effective than the first class of meds prescribed for diabetics. I’ve heard stories of people getting their diabetes under control with lifestyle changes, is there more to it? Is it more diet than exercise that gets blood sugar under control? How do these stories I’ve heard of people getting their diabetes under control via diet and exercise work if exercise (one of the 2 components of diet & exercise) is far less effective than medication? > > Not asking for personal advice, I’m just curious. Well first off you need to recognize that the study looking at the efficacy of metformin was not matching participants to the studies that looked at diet and exercise. Comparing those cited numbers to studies on exercise is not valid. It is not clear to me whether or not the diet/exercise and control groups were _also_ both on metformin or not and what the average starting HgbA1cs were in each group. You need a matched head to head to really make the comparison you are trying to make. Second my impression is that diet/exercise is more promoted both as an adjunct to metformin and prevent prediabetics from progressing into diabetes. I really don’t know how often true diabetics are able to treat their diabetes without progressing to medication as well. In the lprediabetes into diabetes scenario we actually do have a head to head, and [diet/exercise wins](https://www.nlm.nih.gov/databases/alerts/diabetes01.html). > [@](#): > > Participants randomly assigned to intensive lifestyle intervention reduced their risk of getting type 2 diabetes by 58 percent. On average, this group maintained their physical activity at 30 minutes per day, usually with walking or other moderate intensity exercise, and lost 5-7 percent of their body weight. Participants randomized to treatment with metformin reduced their risk of getting type 2 diabetes by 31 percent. > > The findings came from the Diabetes Prevention Program (DPP), a major clinical trial comparing diet and exercise to treatment with metformin in 3,234 people with impaired glucose tolerance, a condition that often precedes diabetes. Now one might think that both together would be even better, but [diet/exercise alone](http://care.diabetesjournals.org/content/35/1/131.full) seems to, if anything, work _better_ than adding metformin to the mix in reducing the risk of prediabetes advancing to diabetes. > [@](#): > > Insulin sensitivity was considerably higher after 12 weeks of exercise training and/or metformin in men and women with prediabetes. Subtle differences among condition means suggest that adding metformin blunted the full effect of exercise training. … Contrary to our original hypothesis, adding metformin did not accentuate the effects of exercise training on whole-body insulin sensitivity in this group of men and women with prediabetes. Consistent with our prior study of acute exercise (18), the addition of metformin may have blunted the response to exercise training alone. … Of course the side effects of diet and exercise are weight loss, increased lean body mass, more strength and greater endurance, along with decreased risk of depression. That’s a pretty big list compared to just diarrhea! (Mind you I am intrigued by metformin as an intervention with broad benefits beyond its blood sugar impacts. But that has been other threads.) ---
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [April 25, 2016, 3:48am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/13 "2016-04-25T03:48:14Z")
> [@Hari\_Seldon](#): > > First thing I should do is explain those percentages. A .5% reduction doesn’t sound significant, but it is. A1C measures what percentage of blood hemoglobin is glycosolated, that is locked in a hemoglobin-glucose complex. So a .5% reduction means a reduction from 7% to 6.5% which is significant. And a reduction from 7% to 5.5% even more so. When I was first diagnosed, my A1C was about 8% and, after a year of using metformin, with no change in the amount of exercise I got, dropped to about 6.5%, consistent with the study reported in the OP. But metformin has an interesting side effect. I lost about 20 lb over the next two years with no changa1e in exercise or diet. A couple years after that, I started on diet and lost another 40 lb and my A1c dropped to 5.5% and stayed there. And I get less regular exercise than I did then. > > When my doctor started me on metformin, he advised me to start with one 500 mg pill every other day and then, after my bowels stabilized, to take one a day for a few days and go onto the regular dose of two pills a day. I never had the least problem. YMMV. I don’t know the mechanism being its weight loss, but metformin is being looked into as an anti-aging compound. > **[The Diabetes Drug That Could Be an Anti-Aging Miracle - Newsweek](https://www.newsweek.com/diabetes-drug-could-be-anti-aging-miracle-404370)** > > Big Pharma is reluctant to test a cheap, generic diabetes pill that could be the fountain of youth. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [April 25, 2016, 3:52am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/14 "2016-04-25T03:52:32Z")
> [@Hari\_Seldon](#): > > … metformin has an interesting side effect. I lost about 20 lb over the next two years with no changa1e in exercise or diet. … FWIW **Hari** the experts seem to think that the weight loss on metformin mainly occurs [by causing decreased intake](http://www.ncbi.nlm.nih.gov/pubmed/9526970). ---
**Author:** ![rbroome](https://avatars.discourse-cdn.com/v4/letter/r/838e76/32.png) [@rbroome](https://boards.straightdope.com/u/rbroome)\ **Post date:** [April 25, 2016, 12:49pm UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/15 "2016-04-25T12:49:36Z")
Cool. My endocrinologist now tells me I need to treasure my Metformin ER-it is much more efficacious than she first realized. She is quite enthusiastic about it now. It used to be just for keeping the peaks and valleys under control. Weight loss, lower A1C, keeps hair on my toes :), etc. I fortunately didn’t know about the stomach problems it might cause so to me it is just another pill. Glad to hear it is so effective. ---
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [April 26, 2016, 12:53am UTC](https://boards.straightdope.com/t/is-metformin-2-4x-more-effective-at-lowering-a1c-than-regular-exercise/752910/16 "2016-04-26T00:53:29Z")
Weight loss on metformin could be caused by activation of AMPK. that is what I’m seeing as the underlying biological mechanism.