Hi! I’d appreciate if someone could help me figure out this one. Lately I started to experiment with my insulin dosage to get the feel of my insulin to carb ratios and insulin sensitivity. I’m currently on Humalog only. My fasting BG is in 85-95 range so still pretty good.
I noticed my BG levels are higher 2 hours or more after eating rather than 1 hour. For example I just had a 35 grams of carbs meal (took 3 units to cover that) and was 93- 1 hour after, 91- 1,5 hours and 115- 2 hours post meal. Yesterday I had 25 grams and took 2 units. I was 110 after 1 hour and 150 after 2 hours. I stayed at 150 for another hour and corrected with 1 unit. I ended at 95- 4 hours post meal.
Does it depend on type of carbs I eat or if I eat more fats with the meal so it slows down the carbs?I’m on a low carb diet so I rarely spike more than 160 with my current diet but still 110 after 1 hour and then 150 after 2?I’m trying to figure this out.
Edit: I now checked again and I’m 153 at 3 hours post meal. Thats after 35 grams of carbs and 3 units of insulin. I just don’t get it.
Sometimes the insulin is faster than the digestion/absorption of food. Yes, low GI foods may take so long to be absorbed that the insulin will sometimes reduce the BG before they change to glucose. 50-60% of protein may change to glucose, too, often taking 3 to 6 hours to do this. Even a small percent of fat will convert to glucose, often taking 8 or more hours! And of course, a high fat meal can slow down everything! Doesn’t diabetes get interesting?
If my BG is in the 70s or low 80s before a meal that includes pasta, I usually wait until after I eat to bolus. Yesterday I forgot that my partner was preparing pasta, so I bolused just before dinner with a BG of 76. I ended up going hypo before dinner was over. I didn’t check to see what my BG actually was then, but I rarely start feeling symptoms higher than 60 these days. I solved the problem by having a beer with my dinner. Liquid carbs go to the bloodstream pretty fast.
You might want to start taking notes of what meals give you what results so you can change your bolus timing depending upon both your pre-meal BG and the carb/protein/fat content and GI value of the foods. I sometimes have to bolus as much as an hour early for the best results, other times after the meal. It depends upon which fast acting insulin one uses as well as differs with individuals.
A general observation is that if your insulin dose matches your meal then you should end up with a blood sugar back where you started after 3-5 hours. What happens in between “depends.” Your blood sugar can spike really high, you can have a hypo at an hour or it can “waffle.” For meals that digest/absorb slowly (like I usually have on a LCHF diet) I will often split dose (on a pump you can extend the dose). I take half the insulin before the meal, leave the needle on the pen and then take other dose after eating.
I stated to notice the pattern that when I eat simple carbs I spike quickly but go down quickly too, whereas complex carbs don’t spike my sugars so much but keep a steady line over 3-4 hour periods. That steady line is in 150s sometimes though. So I’m wondering what is better: quick spike to 180 and quick fall to 120 at 2 hours post meal…or slow rise and average of 130-150 for 2-3 hours post meal?
I’m doing this just as an experiment as I intend to stay on my 50 grams of carb per day diet. But I just want to “play” with my insulin vs carb ratio for a little while to better understand my body.
Dietary fat has no effect on blood sugar levels, except that it can slow the digestion of carbohydrate.
So if you eat a high fat meal, the carbs can take longer to show up in your blood sugar. That’s one possibility. Another, as mentioned above, is low-glycemic-index foods, which can take longer to have their full effect.
Another possibility, which I don’t see mentioned here, is gastroparesis, a fancy term that basically means extra-slow digestion. It is a quite common result of diabetes and something that your medical team should at least consider if this behavior persists and continues.
Actually there were a few studies showing that high-fat, high-carb meals take more than 20% more insulin than a low-fat meal with an equivalent number of carbs.
I would have to know a lot more about the studies to gauge the credibility of the interpretations being placed on the raw data. Bernstein states flatly that it doesn’t work that way. And I have never heard a cogent explanation of the biochemical pathway that supposedly does it. Not saying it can’t be true, just that I have seen nothing convincing. Not yet, anyway.
Here’s one presentation I found that cites a few studies suggesting the combo of high-fat, high-carb requires more insulin:2.1 Wolpert Fat-protein.pdf (1.9 MB)
That presentation states pretty clearly that dietary fat can slow digestion and increase insulin resistance, not that fat is metabolized to glucose. It also says this
However: Marked inter-individual differences, so fixed dosing increase for higher fat meals will not be safe/effective
and this
Protein amounts of O-50g > NO effect on glucose
and this
. . . to achieve optimal glycemic control carbohydrate counting needs to be combined with specific focus directed at identifying whether higher fat (or high glycemic index) meals are contributing to glycemic fluctuations
All of which would appear to reinforce the basic truth that the individual has to empirically determine what works for them without regard to what does or doesn’t work for some other group.
I never said that the fat directly metabolizes to glucose…just that a meal which includes both a lot of fat and a lot of carbs requires more insulin than would be assumed using pure carb-counting.
It is also false that dietary fat has no effect on blood sugar levels. It clearly can raise BG levels – probably not through direct conversion of fat into glucose – but rather through the induction of insulin resistance.
I agree that “what works for each individual” is the only way meals such as pasta can be discussed. After much trial and error, my current procedure is to pre-bolus about 20 min before pasta (with meat sauce) meals but decrease my I:C ratio for that pre bolus, basically “saving” some insulin for a post meal correction bolus that I will take as soon as my BG starts looking like it will rise higher than desired. This reduces the low immediately after dinner. The correction is usually at around 2 hours after meal but final decision is based on the CGM trend and gut feel. The correction dose usually is 1 or 2 units more than I had “saved” from the pre-bolus.
Hope that makes sense…it works for me more than 50% of the time so I am sticking with it until it doesn’t work.
My phrase “convert to glucose” in post 2 may have been in error. The actual phrase used in the U of Wash. carb counting paper was “effect on blood glucose.” The chart shows 10% in 8 hours.
No, you didn’t. But an earlier post (see above) did, and that was what I was referring to. Sorry for the confusion.
“Even a small percent of fat will convert to glucose, often taking 8 or more hours!”
Since we are being meticulous about terminology . . . . no. Fat may increase insulin resistance and, in so doing, reduce insulin’s glucose-lowering effectiveness, but that is not the same thing. Fat doesn’t raise BG. Glucose does.
LOL. My goal in life is definitely not to put on a lot of extra weight. But the main thread was asking how to bolus for foods with varying amounts of fat/carbs/protein, which then went into a debate about whether you need to bolus for fat at all. And the combination of high fat and high carb is definitely a common one in the American diet, as evidenced by the fact that 13 percent of Americans eat pizza on any given day. So I figure people should have some idea that it’s going to take more insulin than just fat or jut carbs or what have you.
