How far up does 1 gram of carb push your blood sugar?

This is supposed to be different by weight, but my chart doesn't always hold up. If you're T1, would you mind giving your weight (Kg or lbs) and what 1 gram of carb raises your blood sugar (mg/dL or mmol)? Exclude yourself if you are on drugs that also raise it or if you are pregnant - sorry, that's too confounding! I'll put together a chart when I have enough data. Any problems you see, let me know.
Like this:
104 lbs: 1 gram carb raises me 6.5 mg/dL

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Well, I'm a type 2, but I do use insulin, so I will answer this anyway, cause I think this is actually important information for everyone to understand about themselves. My answers may differ markedly from an insulin sensitive type 1.

200 lbs: 1 gram of carb raises me 2-3 mg/dl.

I call this my Carb Factor (CF). If you look through the math behind systems like those discussed in "Using Insulin" and "Think Like a Pancreas," this carb factor can be calculated. Given your Insulin to Carb Ration (ICR) and your Insulin Sensistivity Factor (ISF), you can calculate

CF (mg/dl / gram) = ISF (mg/dl / units) / ICR (grams / units)

I use an ICR of 5 and an ISF of 10 to 20 (I'm insulin resistant), and by calculation, my CF is 2-4 mg/dl/g.

ps. Bernstein suggests that 1 g of carbs typically raises the blood sugar of someome with T1 5-10 mg/dl.
1 g doesn't do much to me. I have to do 5-10 g to see a difference. Also depends on the type of carbs. If it's processed, a little raises me 30-50, if it's complex 15-30. Also depends on if I have worked out earlier. If I've worked out, it doesn't do me. If I haven't worked out in a couple days small amounts can cause a spike.

225 lbs, less than 10% body fat pry has something to do w/ it too.
How interesting! We have no charts on processed vs unprocessed carbs or under conditions of workouts vs no workouts raising grams certain distances.
If you look at this question again, would you try 2 glucose tablets in order to be free from processing?
What do 2 glucose tabs raise you - that's 8 grams? Free from a work out!
Agreed; although I am nowhere near 10% body fat...I do agree that the type of carb will change my BG drastically different!
I'm not a math-y type so am not sure how to calculate this ...

My weight is 215 pounds (overweight).
I don't have problems with insulin resistance (although my doses would of course be lower if I lose weight).
I've had Type 1 for 20 years (diagnosed at age 9).

Currently my I:C ratio is 1:9 and my ISF is 1.8 mmol/L.

However, this is my *ahem* "insulin resistant" half of the month. In two weeks my I:C will probably be 1:13 and my ISF will probably be 2.8 mmol/L.

I am not sure if that means my carbohydrate sensitivity changes or what, but my insulin sensitivity definitely changes drastically throughout each month, which drives me crazy.
That would suggest that your Carb Cactor (CF) is between 3.5 and 4 mg/dl/g (0.19 to 0.22 mmol/L), similar to mine. I believe that the CF is proportional weight and that makes sense since your blood volume is proportional to your body size.
How did you figure that, Brian? Wouldn't it be dependent on her target goals?

I actually always wonder when this topic comes up because I don't actually know how many points a gram raises my blood sugar and haven't really thought about it (unlike all the other things I obsess about endlessly!). I think more in terms of target range than specific numbers. I know that if I'm in the 50s I take 2 glucose tabs (8 grams) to bring me up into a decent range, and if I'm in the 40s or 30s I take 3. That brings me up to a reasonable number. So I guess you could say if I am 55 and take 8 grams to raise me to 80, that a gram raises me about 3 points but that isn't terribly exact.

Since you figured it out from Jen's I:C and ISF I'll give you my own (convoluated) numbers. With Symlin my current I:C's are 1:12, 1:14 and 1:30; before Symlin they were 1:6, 1:7 and 1:18. My ISF is 1 unit drops me 45 points. I currently weigh 142.
I'll figure at your weight of 142, 8 grams raises you 25. And I'll figure all the math later via math programs! Thanks!
What I mean is that if your target goals is to raise your blood sugar 20 mg/dl, and your Carb Factor is 4 mg/dl/g, then you should eat 20/4 = 5 grams of carbs in order to raise your blood sugar to that level.

According to my claculator, your Carb Factor (w/ Smylin) is between 1.5 and 3.75. This is within the range you observed of 8 grams raising you 25 mg/dl.

ps. Your ISF seems "low" given your ICR.
Oh yes, I understand the first paragraph, I just never think about "raising my blood sugar 20 points" so much as just "getting it into range".

Which way do you mean my ISF seems "low"? Rather than 1:45 it sounds like it should be 1:50 ish or it should be 1:30ish (all this talk of lower and higher always derails me.) Just curious. Remember my I:C ratios are artificially higher (see what I mean about the language!) due to Symlin aiding the insulin
So, if I lose weight (which I'm working on), would I have less blood volume and thus a gram would raise my blood sugar more?

And, according to this equation I could presumably eat 50 grams of carbs without bolusing and have my blood sugar raise by 10 mmol/L, meaning if I started out at 5.5 mmol/L I'd only be 15.5 mmol/L if I forgot a bolus. That is definitely not true. If I miss a bolus for, say, a 20 gram meal my blood sugar will be around 15 mmol/L. If I forget a bolus for a 50 gram meal, my blood sugar would be 20+ mmol/L. I don't understand how that works.
I think these formulas are great guidelines, Jen, but they don't take into account all the relevant variables and they definitely fail in comparison to plain old trial and error to find out what is true for each of us. Just my opinion!




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