Avoiding post meal spikes

Just wondering what other people do (or don’t do) to avoid post meal bg spikes. Seems it doesn’t matter what I eat, I get the post meal spike everytime. BG usually comes back down before next meal, but those 250’s after every meal are really frustrating. Since getting the cgm several months ago this problem is more recognizable. I want to have those nice flat lines or maybe even gentle curves, anything but the spikes. I’ve tried the low GI plans but they have little effect. Anyone have suggestions?

I have this problem too. I find pre-bolusing helps. Use your CGM to find out approximately when insulin starts hitting your system - for me, it is two hours with Novorapid/Novolog but I have recently switched to Apidra which I much prefer as it’s quicker in, quicker out. I also find that the smaller the meal/the less the carb, the smoother the line. Though even zero carb doesn’t always help me as I can easily go above 140 on a small no-carb meal (like 2 eggs). Bigger no-carb meals (say 2 eggs+bacon+sausage) can easily send me above 180. I have to laugh at suggestions that reducing carb can iron out spikes. How do you subtract from zero?

Depending on the meal, dual wave bolusing helps avoid that, especially if the meal has a lot of slow-digesting carbs. The biggest thing that has helped me, though, is just limiting my carb intake. I too can easily spike over 250 after a meal with a moderate amount of carbs. Also, sometimes bolusing a bit earlier helps too (like 20-30 minutes before eating).

I have the same problem. I just can’t give up carbs.

Pre-bolusing up to 30 minutes before eating has worked for my son…now that is when he remembers to do it :slight_smile:

I have a real problem with consistency, especially in the morning. I can wake up at the same time, very similar waking blood sugar, identical breakfast and bolus (about 45 minutes before eating), same post-breakfast exercise. Today my reading 90 minutes after eating was 52. Other days it is as high as 250, with an identical breakfast and exercise. Not sure why.

I have tried the pre-bolus, I use it especially for eating out (nothing like resturant food to shoot you through the roof). Sometimes the prebolus backfires though. I bottom out before the food arrives and need to eat quick carbs to bring it up - then the food arrives…so in essence I’m “double eating”. The bolus seem to work super fast if I’m low and take at leat two hours if I’m high. Why is that? Anybody not eat until their numbers are below a certain level? Does that work?

I usually won’t eat at 150 or above which doesn’t seem to speed the correction but does prevent further spikes. I eat a great deal of fat as part of my meals including peanut butter, almonds and olive oil which slows things down. Have you checked your basals recently? If your total daily dose is correct but you’re taking too much basal, you’ll have a tendency to go high first and then have the extra basal slowly bring you back down. If you cut your basal and take a bit more bolus, you’ll have a quicker response on the front end.


I agree with what most of the others said. Definitely find the right time to pre-bolus. Find out if there are some foods you just can’t eat and bolus for accurately (for me those are cereal, pasta and rice). If you are high before your meal either correct and wait or just add the correction bolus to your mealtime bolus.

Also, if you are always high after meals it sounds like your I:C ratios need tweaking.

This is becoming a mystery for me as well. After getting the CGM I realized this problem as you did. I began doing pre bolus from 15 to 45 minutes prior to eating. And for about two weeks it was working very well. I was able to achieve several flatline 24 hour periods. I was so happy and thought i had figured it out! And then all of a sudden i am right back to up to 250 and then back down. And it seems no one can explain why this is. So try the pre bolus and hopefully it will hold up for you. I will admit though I am not a low carb guy so that might be causing some of my frustration. I see other people talking about apidra i might have to give that a try if it works faster for a shorter period of time. Because like you say at the end of the 4 hour duration of the insulin my sugar will return to normal. Let me know if you find a good answer to this extremely frustrating problem.


If it were me I’d take notes on what I tried for pre-bolusing and I would focus on non-breakfast meals for the time being (because morning bg is often tricky). Unless your digestion is variable like with gastroparesis, I think you can figure out something that works. If bg is above optimal, then you want to add a correction to your pre-bolus so that the meal spike begins at say 100 (keeps the spike as low as possible). To do this without going low requires coming up with mathematical rules of thumb for calculating how long to wait after pre-bolusing. I use my insulin peak time and ISF.

I use 90 minutes as my insulin peak time and my ISF is 66. Example: pre-meal bg=130, carb count of my upcoming meal is 3 units, and my target bg before the meal spike begins is 100. I know it takes 0.50 unit to drop me from 130 to 100, so I will pre-bolus 0.50 plus 3.00 units=3.50 total. Now here comes the math to figure out how long to wait before eating: I want to drop 30 points which is represented by 0.50 units, so 3.50 divided by 0.50 is 7. I divide 90 minutes by 7 to get a wait time of 13 minutes. I use a timer so I don’t ever forget to start eating and cause myself a low. I use this formula every time I eat cereal which spikes me above 200 otherwise.

Your formula would depend on your insulin peak time and insulin sensitivity factor and maybe other factors that your CGM can maybe reveal. Hope this helps (not?).

you can do the same by having higher basal at meal time and lower basals later. But more importantly, I have lowered basal rates and increased the carb ratio so that I get enough insulin to cover the meal and I do not pre bolus unless I am over say 150. You all may think this is crazy, but trust me on the next one. It really works. To slow the glycemic index and avoid the spikes after meals, mix 4 teaspoons lemon juice in a tall glass of water and add some splenda. This is 2 carbs so add to your bolus. It really helps level out the peaks and valleys. Also it is important to avoid hi glycemic index foods - White bread, white rice stick more with high fibre complex carbs.

If I increase my carb ratios, I still get the spike and then I bottom out before the next meal. I’ve tinkered with this for years. The spike seems to be inevitable with any carb. And a girl can’t live on meat alone. I already restrict high GI foods. The lemon juice idea sounds interesting. Any idea why it works? I drink water with lemon all the time, is there a cumulative effect or does it need to be all at once?

If you are bottoming out before the next meal, then that might have more to do with your basal which may be set too high. If your basal is set right, then you should be able to increase your bolus (your I:C ratios) to the right levels until you don’t spike. I think this might help you a lot more than lemon juice! Have you basal tested? You should remain steady without eating. What basal are you on? Levemir is more stable than Lantus, and two shots are more stable than just one. Best of all for stabalizing basal levels is the pump, because then you can have different basal rates to meet your needs throughout the day.

I’m on the pump and fasting for extended periods shows my basals to be pretty stable. That’s why I’m so frustrated by the after meal spikes. I do most everything right and still get them.

I take it with the meal and the guide I saw said 4 teaspoons so its like a glass of lemonade (Splenda of course) I am told that it slows the emptying of the stomach and it is supposed to reduce the glycemic index 30% also maybe a lil less on the basal and a lil more on the biolus can help. Also Novolog vs humalog makes a big difference Novolog is superior works faster and a lil stronger

My gut still tells me you should increase your mealtime bolus until you no longer spike. and if you are having lows before the next meal consider lowering the basal for the time period 2-3 hours before the lows occur.

Also, if you don’t already, experiment with times that you bolus. At least 15-20 minutes before a meal and some people do more.

Finally, I’m just starting on Symlin (so I’m no expert) but some people have had very good experience lowering post meal spikes with it, but it’s definitely a whole other complexity in dosing, so I’d try other things first.

ZOE, I agree with the increase in Bolus decrease in Basal. The other thing worth trying that I have had great luck with is using Metformin. I have used for years and now my wife has also started on it and it helps decrease the spike - I am usually less than 120 and nearly always less than 150 after a 35 carb meal.

I am curious about the symlin. I listened to a JDRF video yesterday nd they are sponsoring a project to blend symlin with insulin - they claim it looks promising. Keep us posted on how it goes

I have to respectfully disagree with dickengel about GI. I have found that there is little difference between low or high-GI foods for me. What matters more is the total amount of carb. Maybe I have some special ‘get out of jail’ card for croissants but I usually have very respectable numbers after croissants. Wholegrain bread however spikes me crazily.

Sarah, at the moment I might have an unrelated medical reason for needing to avoid post meal spikes. I have been working my butt off and pleasingly, have had a few days of almost perfect blood sugars, with almost no spikes. I have been able to do it by only ever eating a maximum of 15g of carb at one go, and keeping all meals small. I don’t know how sustainable this is in the long run but it’s working for now. I am on a poor person’s CGM/pump and am probably oozing residual blood on the keyboard even as I type this lol!

I guess as they say - YMMV - But whole grain bread is not that low in the index - I do (and my wife does too) notice significant different spikes with high vs low glycemic index foods - 15 grams of carbs is kinda low to survive on i will do 35 to 50 generally without a spike of more than 20 to 40 points.