• Guest - w'd love to know what you think about the forum! Take the 2025 Survey »

Varying insulin:carb ratio depending on the amount of carbs?

Alzibiff

Well-Known Member
Messages
76
Location
North Manchester
Type of diabetes
Type 1
Treatment type
Pump
I've been using an insulin pump for around two and a half years now after 40 odd years of injections. This followed my attendance on a DAFNE course in 2009 which totally changed my whole attitude and day to day management of my diabetes - the whole experience is now far more 'scientific' although I am still looking for the holy grail which is that perfect balance between food intake and the amount of insulin delivery - and to get that perfect balance EVERY DAY!

Of course, no matter what numbers come out of the blood glucose meter, high, spot-on or low - there's always a reason - and the skill of proving such reasons is something, which in my experience, doctors and DSNs are very very good at. It goes without saying by the way, that I am always very careful not to do any basal or bolus ratio changes without looking for such "reasons" - stress, previous lows, previous highs, that extra bit of exercise, a meal consising of slow release carbs - the list goes on.

However, I would appreciate comments on the following as I think I may have come across another "reason" for silly/frustrating BG readings.

After a lot of monitoring and testing, I finally got things to click for a few days in terms of getting decent BG readings when I wake up and maintaing these during the day. However, after what was a rather uneventful day, (in terms of all those 'could be' factors), my evening meal was one which had a significantly lower amount of carbs than normal and consequently required a lower amount of insulin bolus.

Next morning, a BG reading of 10mmol/l rather than the 5 or 6 I was getting used to. My question is this - on the admittedly big assumptions that I have my basal rate correct and that the carbs released by my meal were at a rate which is similar to 'normal' happenings - could it be that when the carb count is low, the insulin ratio required to digest them is higher than when the carb count is high?

Example - with a ratio of 2 units per 10g Carbs: a 30g carb meal would require 6units, a 60g carb meal would require 12units but my experience suggests that although the units required are correct for the 60g carbs meal, the amount taken for the 30g carbs meal is too low. Does it make sense to increase the ratio slightly when taking a lower amount of carbs in a meal?

Or are there far too many variables in all of this basal/bolus thing to get consistently good readings all of the time?

Thanks for reading - sorry to make this such a long post.

Alan
 
Re: Varying insulin:carb ratio depending on the amount of ca

Hi Alan,

If the meal you ate contained a lot of protein, then that could explain the later rise.
 
Re: Varying insulin:carb ratio depending on the amount of ca

I agree with slim Tony......low carb, or even no carb meals still need me to have some insulin...just a tiny amount, but if I don't my BGrises. I also think it is teh protein. I look at it, that the protein effect is always there, but it often masked by the carbs that are a none low carb meal..if you are having say, a 40g CHO potato...than the effect from protein is tiny, but in your calculations, you are actually including it in what you think of as the carb:insulin ratio.

Sorry, not very scientific!
 
Re: Varying insulin:carb ratio depending on the amount of ca

Mmmm - think that what you have both said is effectively what I was getting at although the effect of protein & fats should best be catered for by either a square wave or dual wave bolus.

The "..no carb meals still need me to have some insulin.." point is well made but seems to fly in the face of other, maybe "theoretical" advice. Yup - it's all much more complicated than things first appear - at least of that I am definitely certain!

Alan
 
Re: Varying insulin:carb ratio depending on the amount of ca

Some people use a system called TAG; total available glucose . This takes carb counting 2 steps further and attempts to calculate insulin according to carbs, protein and fat. Personally I think it's 2 steps to far! and just include a fiddle factor when eating a very low carb meal.(ie guess)
This article has quite a lot of links about it including an amazon link to a book that introduced the idea , over thirty years ago.
http://controllingtheuncontrollable.wor ... ucose-tag/
 
Back
Top