Metformin Lowers Testosterone?

[n2turbo]

I have been taking Metformin for just the benefits. For the past year, I am not diabetic. I was not under the impression that it lowers your testosterone. I was informed by my doctor that it lowers your testosterone. And I also jumped online and looked apparently it does. I don’t know if this is true or not. I know a few other people that are taking this with their protocol. Just curious if this is true. If it’s true seems very counterproductive.

 

[Jay-Jay]

I've been on TRT 9 years and Metformin 4-5 years and total T has been very stable, with no noticeable change. It may be, in part, that the Metformin dose is relatively low, 250mg 3x per day.

 

[Nelson Vergel]

If you have metabolic syndrome, it can help. Otherwise, I doubt it.

Metformin improves semen and testosterone in men with metabolic syndrome

Metformin improves semen characteristics of oligo-terato-asthenozoospermic men with metabolic syndrome Fertility and Sterility Volume 95, Issue 6, May 2011, Pages 2150–2152 Forty-five patients (age range: 26 to 44 years) were evaluated. Five patients experienced mild side effects such...

www.excelmale.com

It may reduce aerobic capacity and muscle mass.

Metformin Decreases Aerobic Capacity, Muscle Mass and Testosterone

I have been on 2x1000mg a day but I lost my endurance(Kun Khmer/Muay Thai training) and workout capacity/volume. I had no common sides from it, no diarrea etc, but felt physically limited. A strange feeling of being limited by the amount of energy the body had stored or could generate on the...

www.excelmale.com

 

[Vtail]

Metformin Recall . . .

Metformin Was Recalled in 2022—What To Know

The Food and Drug Administration issued a metformin recall in January 2022. Learn about NDMA and your next steps if there's another recall.

www.health.com

 

[Vince]

I'm a long time user of metformin. I use it because it's the longevity drug. If I get my A1C under 5.0, then I figure I can stop. Most health experts tell you, your A1C should be between 4.0 and 5.0. 5.0. so far my A1C has been running at 5.1. I'm getting close but haven't made it yet.

 

[Vtail]

Vince - Are you saying that A1C will continue to drop the longer you stay on Metformin? I began Metformin a few months ago and my A1C dropped from 5.6 to 5.3, which is great however if it continues to drop I would be even happier. I was surprised that by blood glucose did not change at all, and continues to come in at around 100 every time its tested for the last 10 years (I'm 57). My diet/weight are good and I work out quite often.

 

[Vince]

Vince - Are you saying that A1C will continue to drop the longer you stay on Metformin? I began Metformin a few months ago and my A1C dropped from 5.6 to 5.3, which is great however if it continues to drop I would be even happier. I was surprised that by blood glucose did not change at all, and continues to come in at around 100 every time its tested for the last 10 years (I'm 57). My diet/weight are good and I work out quite often.

My A1C was stuck at 5.3 through 5.7. until I added high dose melatonin. I'll see what happens as I continue supplementing with melatonin.

 

[xcpatr922]

my A1c is now 5.1 post TRT ; it used to be 5-5--5.7 prior to TRT. Same like Vincent, I use metformin for longevity only. I don't take it all the time though. I only use it when I HAVE to eat carbs. The impact is very very noticeable. I don't feel so much crash after eating carbs.

Combining TRT with Metformin is very good for carb-sensitive people like me. In fact I can actually start eating carbs a little bit more these days without feeling the impact.

The T level is more dosage-dependent rather than Metformin causing any impact on T.

 

[xcpatr922]

Vince - Are you saying that A1C will continue to drop the longer you stay on Metformin? I began Metformin a few months ago and my A1C dropped from 5.6 to 5.3, which is great however if it continues to drop I would be even happier. I was surprised that by blood glucose did not change at all, and continues to come in at around 100 every time its tested for the last 10 years (I'm 57). My diet/weight are good and I work out quite often.

In my experiences:

the average of the day of glucose is impacted highly by what I eat the night prior. If I skip dinner, my avg glucose for the morning (and avg for the rest of the day) is between 80-95. If I eat late dinner (anything), guess it's like 100-105.

Also if I take cold shower everyday and do lot of walking/hiking, the BG is just dropped continuously to the lowest-normal possible. Without Metformin.

 

[Vince]

my A1c is now 5.1 post TRT ; it used to be 5-5--5.7 prior to TRT. Same like Vincent, I use metformin for longevity only. I don't take it all the time though. I only use it when I HAVE to eat carbs. The impact is very very noticeable. I don't feel so much crash after eating carbs.

Combining TRT with Metformin is very good for carb-sensitive people like me. In fact I can actually start eating carbs a little bit more these days without feeling the impact.

The T level is more dosage-dependent rather than Metformin causing any impact on T.

I also follow a low carb diet. I believe it really helps fight diabetes and heart disease.

 

[Fernando Almaguer]

In my experiences:

the average of the day of glucose is impacted highly by what I eat the night prior. If I skip dinner, my avg glucose for the morning (and avg for the rest of the day) is between 80-95. If I eat late dinner (anything), guess it's like 100-105.

Also if I take cold shower everyday and do lot of walking/hiking, the BG is just dropped continuously to the lowest-normal possible. Without Metformin.

loving the cold showers and cold baths. This morning was nice and cold. Metformin has been pretty good too

 

[mcs]

I have been taking Metformin for just the benefits. For the past year, I am not diabetic. I was not under the impression that it lowers your testosterone. I was informed by my doctor that it lowers your testosterone. And I also jumped online and looked apparently it does. I don’t know if this is true or not. I know a few other people that are taking this with their protocol. Just curious if this is true. If it’s true seems very counterproductive.

It definitely tanked my levels (see below) and I would advise the anyone who's not T2D be aware of this and perhaps not take it unless you're hormonally optimized (on TRT).

• June, 2022 (pre-Metformin): TT: 553; FT: 76.9
• August, 2022 (1 month Metformin): TT: 415; FT: 70.2
• November, 2022 (4 months Metformin): TT: 318; FT: 61.7

 

[mcs]

I posted my T labs above. I think it's pretty obvious Metformin had a sustained down-regulating effect on my levels. I will test again soon to see if it leveled off.

How many others have seen their T levels plummet when on Metformin (on or off TRT)?

 

[Deleted member 43589]

It definitely tanked my levels (see below) and I would advise the anyone who's not T2D be aware of this and perhaps not take it unless you're hormonally optimized (on TRT).

• June, 2022 (pre-Metformin): TT: 553; FT: 76.9
• August, 2022 (1 month Metformin): TT: 415; FT: 70.2
• November, 2022 (4 months Metformin): TT: 318; FT: 61.7

Rapid Changes in Serum Testosterone in Men With Newly Diagnosed Type 2 Diabetes With Intensive Insulin and Metformin

OBJECTIVE. To investigate the effect of metformin on testosterone levels in men with type 2 diabetes mellitus (T2DM).RESEARCH DESIGN AND METHODS. Seventy m

diabetesjournals.org

RESULTS
Total, free, and bioavailable testosterone increased significantly within 5 days (all P < 0.001). After 1 month, compared with the control group, the metformin group had lower total (12.7 vs. 15.3 nmol/L), free (0.20 vs. 0.24 nmol/L), and bioavailable (4.56 vs. 5.31 nmol/L) testosterone (all P < 0.05).

So metformin did cause a significant reduction in endogenous testosterone production after 1 month. It is thought that metformin inhibits cytochrome P450-C17a, a key enzyme in the synthesis of steroid hormones. However, the longer-term effect of metformin on testosterone and sexual function remains uncertain. Obviously from your blood testing @mcs, there was also a significant reduction in total T levels after about 6 months of use. But as you pointed out, being on TRT should keep the levels higher.

Observation - lots of competitive bodybuilders use metformin in the bulking cycle to avoid putting on body fat while consuming extra calories and carbohydrates. It also helps avoid insulin resistance with high doses of HGH. Metformin increases glucose uptake into muscle tissue (incresed sarcoplasmic hypertrophy) while simulating fat loss, improves cholesterol values, and results in an overall improvement in metabolic health.

 

[mcs]

Rapid Changes in Serum Testosterone in Men With Newly Diagnosed Type 2 Diabetes With Intensive Insulin and Metformin

OBJECTIVE. To investigate the effect of metformin on testosterone levels in men with type 2 diabetes mellitus (T2DM).RESEARCH DESIGN AND METHODS. Seventy m

diabetesjournals.org

RESULTS
Total, free, and bioavailable testosterone increased significantly within 5 days (all P < 0.001). After 1 month, compared with the control group, the metformin group had lower total (12.7 vs. 15.3 nmol/L), free (0.20 vs. 0.24 nmol/L), and bioavailable (4.56 vs. 5.31 nmol/L) testosterone (all P < 0.05).

So metformin did cause a significant reduction in endogenous testosterone production after 1 month. It is thought that metformin inhibits cytochrome P450-C17a, a key enzyme in the synthesis of steroid hormones. However, the longer-term effect of metformin on testosterone and sexual function remains uncertain. Obviously from your blood testing @mcs, there was also a significant reduction in total T levels after about 6 months of use. But as you pointed out, being on TRT should keep the levels higher.

Observation - lots of competitive bodybuilders use metformin in the bulking cycle to avoid putting on body fat while consuming extra calories and carbohydrates. It also helps avoid insulin resistance with high doses of HGH. Metformin increases glucose uptake into muscle tissue (incresed sarcoplasmic hypertrophy) while simulating fat loss, improves cholesterol values, and results in an overall improvement in metabolic health.

I am not T2D but prone to it, so unlike the test subjects, am taking Metformin electively as a geroprotective and prophylactic agent. The question is whether staying on it indefinitely will eventually necessitate TRT. I was already low normal and considering TRT [June, 2022 (pre-Metformin): TT: 553; FT: 76.9]. This pushed me over the edge with a TT level of 313. I will have the followup labwork done soon.

 

[Deleted member 43589]

That is a question that science can't answer. With your last T readings at a level that qualifies as androgen deficient, you may have to make a decision. Taking metformin sure has some good benefits but adding TRT can solve the problem of it lowering T levels. Keep us informed when you get your next lab work done.

 

[mcs]

1 month update - officially in the tank whether it's from Metformin or not.

Latest labs as of 12/6 are confirmatory for secondary hypogonadism:

TT: 347
FT: 48.2
BIO: 99.2
SHBG: 30
E2: 11

Again, main concerns with proceeding with TRT:
Given my history of hypercoagulopathy (past clots in both legs; currently on a blood thinner), hypertension (taking BP meds) and sleep apnea (CPAP), I am considering experimenting with T secretagogues other than frank TRT like enclomiphene or
kisspeptin-10.

Thoughts?

 

[jacb]

I'm a long time user of metformin. I use it because it's the longevity drug. If I get my A1C under 5.0, then I figure I can stop. Most health experts tell you, your A1C should be between 4.0 and 5.0. 5.0. so far my A1C has been running at 5.1. I'm getting close but haven't made it yet.

Hi Vince

When you talk of 4.0, 5.0 etc - What units you are using?

Here is a link to a HbA1c converter: LINK

I have been given an HbA1c of 51 mmol/mol ... that is 6.8% dcct/ngsp according to the conversation calculator.

If your units are % dcp/ngsp, I find it interesting that you are aiming for 4/5% which I believe equates to 20/31 mmol/mol ... That seems VERY low. Wouldn't Hypoglycemia be a real concern?

My GP is suggesting 5/6 (Units unknown- Which is why I started looking at this unit conversion Issue). I believe that 5/6% equates to 31/42 mmol/mol.

 

[Vince]

Hi Vince

When you talk of 4.0, 5.0 etc - What units you are using?

Here is a link to a HbA1c converter: LINK

I have been given an HbA1c of 51 mmol/mol ... is that 6.8 in your units?

Interesting that you are aiming for 4/5 which I believe equates to 20/31 mmol/mol ... That seems Very low. Wouldn't Hypoglycemia be a concern?

My GP is suggesting 5/6 (which is why I started all this unit conversion thing)

I believe that this equates to 31/42 mmol/mol

Sorry, I'll have to look it up.

 

[Fernando Almaguer]

Sorry, I'll have to look it up.

what dose of Metformin do you take Vince?