I have been T1 for 8 years now with an IC of 20. Starting about 2 weeks ago, my sugars started rocketing after meals. It is like my body is rejecting carbs. With trial & error, I am taking 30-70% more insulin per meal. The new IC is closer to 15 now. I would say I am developing insulin resistance but then why hasn't my basal requirement also increased? It appears that the lower the Glycemic Index, the less extra insulin I need. Have any of you experienced similar carb "intolerance" and how do you explain and manage it? Should I just limit carbs and add exercise? Can anyone offer an experience?
Have you tried using a fresh supply of insulin? Have you gained any weight over the last few years? Are you above your ideal weight? Are you on shots (MDI) or a pump? Do you know how many grams of carbs that you consume in a day? In one meal? What meals make this worse?
Hi Terry,
Small weight gain (5 lbs maybe) but admittedly I was eating a lot of desserts and have always eaten high carb. I take 11u basal on a pump. I cut back on junk and max at 250g carbs daily for 10 days now. For a 49g of carb bagel, I need 28% more. For 2 pbj's, I need 70% more. For a smoothie of yogurt and spinach, I need 40% more. The only meal that hasn't needed an increase is my brown rice and veggie meal (a low GI meal) although I do have to shift about 13% from the 2nd shot to the 1st shot to cover this meal.
I am puzzled why my basal hasn't gone up as well. I am guessing my carb heavy diet has shifted my metabolism in some way to being carb intolerant.
I keep my insulin in the fridge.
Oh, and I've lost about 3lbs in the last week.
a 1:15 is normal for a type 1, i weigh 105 lbs, have been type 1 for a bit over 2 years and do a 1:8 for breakfast and 1:11/12 for lunch (on pump) and am insulin sensitive. I also low carb, you're eating much more carbs then I do. i however, don't like a lot of movement with my blood sugars so I probably bolus more then I should. basal has nothing to do with food or meal intake. However, basal is the background and foundation to everything, maybe your basal is off.
Don't you carry around your insulin vial with you if on a pump, i.e., how could you keep in fridge, just curious?
I calculate your total daily dose of insulin at 11 units basal + (250 grams CHO/20 = 12.5) = 23.5 units. You are relatively sensitive to insulin. Based on what you've written, I'm guessing that your I:C ratio has changed. Instead of 1:20, perhaps it is closer to 1:18 or 1:15.
You could experiment using a more aggressive I:C. I would suggest that you keep a written record of your insulin dose as well as a careful calculation (swagging not advised!) of the carbohydrate content of your meal. Ideally your BG will not exceed 140 mg/dL at 2 hours post-meal and return to your pre-meal BG at 4 hours post-meal. I would do a fingerstick BG test at mealtime, then at 1, 2, 3, and 4 hours after eating. Do not eat anything else after your meal unless you need to treat a low BG.
How do you know that your basal requirements have not changed? Have you done any formal basal tests? If you're not 100% sure about your basal profile, I would do basal testing first, then address the I:C ratio adjustment. It's easy to have an incorrect basal rate need help from the I:C dose or the other way around. An ideal basal/bolus regimen would be a basal rate that simply counteracts the glucose output from the liver only and the nutritional bolus take care of rise in glucose from food only. That's the ideal and it's easier said than done. Even if you do get it dialed in, things do change.
Good luck.
Are you trying to lose weight? Did you increase exercise or reduce your food intake?
Tx. Have not formally basal tested but I have been level at night and if I were insulin resistant, surely my overnight basal would be insufficient. I assume that daytime levels are correct but haven't really verified because my new meal bolus regimens appear to work which suggests the problem is with the carbs. The vial that I am using for insulin is over half-way gone which means that it was working prior to this recent increase in need for insulin at meal-time.
I wish I understood what was going on metabolically, i.e. why my IC ratio has increased without a corresponding increase in basal need. I'm not finding any theory except that people report needing more insulin (bolus & basal) if they gain enough weight.
reduced carbs by cutting out desserts
Granted, an IC of 15 is pretty typical but the increases I have needed recently would be enough to drive low after low under normal circumstances for me.
Perhaps your pancreas had been putting out a small but helpful level of insulin but now it's slowing down. Just a thought.