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How much does blood glucose rise after eating 10g of carbs

Art Of Flowers

Art Of Flowers

Well-Known Member
Messages
1,299
Location
Kent
Type of diabetes
I reversed my Type 2
Treatment type
Diet only
Dislikes
Statins
I read online that 10g of carbs can increase blood glucose by 2-3 mmol/l. Is this correct?

I ate a mochi Japanese snack which has 20g of carbs and my glucose spiked about 6 mmol. I think I may avoid these in the future.

Today is my first time using a CGM - Dexcom One+
 
Well done on launching into experimentation with your CGM. It is a fantastic tool for learning to individualise your diet and lifestyle interventions.

While there might be some rough estimates of carb impact on your blood glucose out there, it will be very individual and depend on your metabolism, the food you are consuming, and your starting blood glucose. You might even get different results if you try and repeat the same experiment in similar conditions multiple times.
 
I suppose how long is piece of string? But 6 is nowhere near a spike and is a very very normal number even for someone without diabetes. If that’s where you were 2 hrs after then it seems the food you ate was fine - what were you before you ate the snack?
 
I would think the rise to be very dependent on the person, or even the time of day, and can not really be predicted?
If I eat something in the morning it has a much bigger effect on my bg than when I eat the same thing late in the afternoon.

From personal experience, prepare for some surprises from your cgm bg wise.
Biggest surprise for me was that even brands of food can matter. Had brand A of port that did nothing to my bg. One time they did not have brand A so bought brand B. It send my bg through the roof.
 
TheSecretCarbAddict said:
Well done on launching into experimentation with your CGM. It is a fantastic tool for learning to individualise your diet and lifestyle interventions.

While there might be some rough estimates of carb impact on your blood glucose out there, it will be very individual and depend on your metabolism, the food you are consuming, and your starting blood glucose. You might even get different results if you try and repeat the same experiment in similar conditions multiple times.
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This is the first time using a CGM since being diagnosed at T2 back in 2016. I did look into CGMs a few years ago and concluded they were too expensive (over £150/month) but now the cost has come down to around £80/month for the Dexcom One+ and £100/month for the Libre 2 plus. A few years ago you had to buy a separate Dexcom transmitter as well as the sensors, plus buy a reader. The newer CGMs from Abbott and Dexcom have integrated transmitters and use mobile phones as the reader.

I think it is now viable for many T2 people to self fund CGMs. I will probably get a monthly CGM subscription for a while.
 
Art Of Flowers said:
This is the first time using a CGM since being diagnosed at T2 back in 2016. I did look into CGMs a few years ago and concluded they were too expensive (over £150/month) but now the cost has come down to around £80/month for the Dexcom One+ and £100/month for the Libre 2 plus. A few years ago you had to buy a separate Dexcom transmitter as well as the sensors, plus buy a reader. The newer CGMs from Abbott and Dexcom have integrated transmitters and use mobile phones as the reader.

I think it is now viable for many T2 people to self fund CGMs. I will probably get a monthly CGM subscription for a while.
Click to expand...
It was one of your posts that pointed me to Dexcom ONE+ subscription. I've historically been on Libre and a bit of pain managing historical data if I transfer to a different platform, but the cost difference might make it worthwhile to move to Dexcom. I have ordered one Dexcom ONE+ sensor to test and comapre. Keen to compare precision and app features, but from reasing Dexcom seems to integrate more easily with a range of other health platforms. Will create a new thread on this when I get the sensor and have had a chance to do a side by side comparisons.
 
One of the things that is not discussed because of the one size fits all approach from health industry is intolerance to carbs,.
I would imagine that this 10g test was done on a non diabetic.
As was the glucose index and the insulin index.
Even then, there can be a correlation.
Insulin resistance and the first phase is important to how the response to carbs effects us.
How much insulin you produce to that quantity of carbs will be different for each of us.
As does the second phase, and if you don't produce enough.
This is why T2s can have a diet approach and others dont, and need insulin to help with the high spikes.
This is why low carb helps in control. Cos it reduces the spikes and insulin(over time) becomes more useful, as the blood glucose range, hba1c levels are lower.
Your body becomes healthier the more constant levels near normal as possible.
And to add, the 10g will have different results the healthier you become.
And to add. My spike from 10g from fasting levels of 6.3 is 6.8.
And of course fasting or non fasting makes a difference.
Hope that helps.
 
Your reading of 6 mmol/ls is great and a completely normal reading. Mine unfortunately rises to around 10 mmol/s on very few carbs. A single grape will send mine shooting up. I love grapes :( .

Like @EBe66 says it also depends on the time of day. My blood sugars tend to be much higher in the afternoon, which correlates with the general consensus that insulin resistance increases later in the day for most people, including non diabetics.

Once you have lost your first phase insulin release things become more iffy. The first phase rapid insulin release, is that quick burst of insulin you get when you consume carbs or anything that will raise your blood sugars. So , I’m thinking that if your metabolism is working as it should a small amount of carbs will be dealt with quickly by this initial release within minutes of consuming them, thus your blood sugars only rise slightly. Your second phase insulin release comes after. This is a more sustained insulin release, the big guns if you like. The pancreas will continue to secrete insulin until your blood sugars come down. I believe that is one of the reasons why your blood sugars can go higher and longer without that initial burst of insulin. Also it depends how sensitive you are to insulin and how bad your insulin resistance is. The other factor is , as @Lamont D says, depends on how much insulin your pancreas is capable of producing. Not everyone‘s pancreas’ are made equal. A non diabetic can potentially produce a lot more insulin , along with an optimum first and second phase insulin release.
 
Art Of Flowers said:
I read online that 10g of carbs can increase blood glucose by 2-3 mmol/l. Is this correct?

I ate a mochi Japanese snack which has 20g of carbs and my glucose spiked about 6 mmol. I think I may avoid these in the future.

Today is my first time using a CGM - Dexcom One+
Click to expand...
By 6mmol or to 6mmol?

significant difference between the two things
 
Art Of Flowers said:
I read online that 10g of carbs can increase blood glucose by 2-3 mmol/l. Is this correct?

I ate a mochi Japanese snack which has 20g of carbs and my glucose spiked about 6 mmol. I think I may avoid these in the future.

Today is my first time using a CGM - Dexcom One+
Click to expand...
I’d also check if they had discounted any polyols or sugar alcohols in that count. Some labels discount all polyols yet some most definitely can cause a spike in some people. Usually maltitol.
 
As a type 1 rises per mmol each 10gm of carb from food are extremely important to work out as that is how we work out our insulin requirements.
However, it is not written in stone. We are all different. It can be slightly higher and slightly lower. Each food item can be different regardless of how many carbs you think are in it. And all that is before the time of day is factored in.
Record keeping and experimentation is the key to finding out your own thresholds.
 
becca59 said:
As a type 1 rises per mmol each 10gm of carb from food are extremely important to work out as that is how we work out our insulin requirements.
However, it is not written in stone. We are all different. It can be slightly higher and slightly lower. Each food item can be different regardless of how many carbs you think are in it. And all that is before the time of day is factored in.
Record keeping and experimentation is the key to finding out your own thresholds.
Click to expand...
I suppose it depends on what the IOB is doing for us T1s….

On average when I know it’s just a basal low 10g would do it for me. Raising my BG by 3 or 3.5mmol. (Putting aside any active basal.)
The foot on the floor liver dump thing is consistently the same. Thus I’ve worked out my liver can push out the equivalent of 2 jelly babies?
 
what Have found is there is no hard and fast rule , there is no printed sheet telling you how much insulin is needed for x amount of carbs , the only way to find out what works for you is experiment , sounds quite drastic but it’s not , you have to try different things ! And when you do diabetes doesn’t seem so restrictive
 
My BG readings on my contour plus yesterday were 7.0 at 07:13 7.4 at 08:20 and after eating a mochi were 13.2 at 09:30. The only other thing I had eaten was a few walnuts. My new One+ CGM showed a rise from 6.6 to 11.2. This is before I calibrated my CGM.

A mochi is a small round rice cake with a filling, e.g. red bean paste with 20g of carbs. My CGM was showing a rapid spike in blood sugar which lasted about 2 hours before returning to normal. That was in sharp contrast to my low carb lunch which only raised my glucose by 1.3.

I wasn’t expecting that one small snack could have such a huge glucose impact.
 
Art Of Flowers said:
My BG readings on my contour plus yesterday were 7.0 at 07:13 7.4 at 08:20 and after eating a mochi were 13.2 at 09:30. The only other thing I had eaten was a few walnuts. My new One+ CGM showed a rise from 6.6 to 11.2. This is before I calibrated my CGM.

A mochi is a small round rice cake with a filling, e.g. red bean paste with 20g of carbs. My CGM was showing a rapid spike in blood sugar which lasted about 2 hours before returning to normal. That was in sharp contrast to my low carb lunch which only raised my glucose by 1.3.

I wasn’t expecting that one small snack could have such a huge glucose impact.
Click to expand...
Some of us (T2 at least) do find certain carbs have a disproportionate effect on our levels. It might be legumes, tomatoes, rice bread or whatever. Not sure why this is but it’s definitely a thing. Identifying any of your own personal kryptonite items is part of the challenge I guess
 
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+1 for the disproportionate effect on carbs. I made the mistake of having 2 weetabix which should have been around 26g carbs. My blood sugar spiked much much higher than a full roast dinner I've eaten before, with more overall carb intake in it.

Although it also depends on what you eat with the carbs, fibre, protein etc.
 
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