Bolusing for Protein

So, in an effort to lose weight and curb my addiction to carbs, I’m starting on the (slightly modified) South Beach diet plan. What I hope some of you low-carbers can help me with is this: If you’re eating a meal that is very low in carbs (i.e., some meat and low-carb veggies), how do you bolus for that?

In the past I’ve found that when I’m just eating protein, with very few carbs, if I just bolus for the carbs I go quite high at the two hour mark. But I have no idea how to bolus for protein. Ideas? Thanks in advance for your input!


Some dose for protein using about 50% of ratio for carbs. There are many discussions, some use the term TAG for total available glucose, and include fats and proteins in calculation.

I don’t have an exact calculation, but do include bolus for fats and proteins, based on experience with similar meals and dexcom to show trends.

I’m now using an automated insulin dosing system that takes care of fat/protein dosing. For several years I did dose explicitly for carbs, fat and protein.

Here’s what I did but please do your own experimenting to discover what works for you. All of this dosing is premised on a carb-limited diet. I eat about 60 grams of carbs per day or less. Most meals are limited to less than 20 grams of carbs. The reason I say this is that insulin dosing for protein needs to take place in a carb limited environment. A person eating an abundance of carbs will not need to convert protein to glucose and will therefore not need a protein insulin dose.

In addition to the usual carb bolus, what I did was add 50% of the protein grams and 10% of the fat grams to get a total that I called carbohydrate equivalents. I then treated this number like a carb for calculation purposes.

I divided this carb equivalent total by my insulin to carb ratio to arrive at a total insulin dose for fat/protein. I delivered this fat/protein equivalent carb dose as an extended pump bolus at the maximum hourly rate of 1.2 units per hour. You will need to confirm this by your own personal experimentation. This is what worked for me.

For example, let’s say I wanted to eat a meal with 60 grams of protein and 50 grams of fat, I would calculate the equivalent carbs by taking 50% of the protein grams and adding it to 10% of the fat grams. In this case (60 grams x 50%) + (50 grams x 10%) = 30 + 5 = 35. If you have an insulin to carb ratio of 1:7 then divide 35 by 7 which equals 5.

So, if you limit the extended bolus to 1.2 units per hour, you would deliver 5 units over 4.5 hours or about 1.1 units/hour.

I am not saying that this is a formula that will work for you. I am not a doctor or dietitian. You can use this, however, as a basis to begin your own experimentation.


I find I really need to bolus for protein and fat, no matter how much or how little carbs I eat. I eat a moderate carb diet with an average of about 25 carbs a meal. I usually have a very small snack about an hour before bed. Depending on how I am running, I usually will bolus for the protein and fat. I use a 50% plus 10% fat as
an extended bolus, weighing in toward the conservative. After doing a bunch of experiments, I extend the bolus for fat and proten with the consideration of how long it takes it to digest. FOR ME this seems to work. YDMV. For instance red meat I will extend for 3 to 3 1/2 hours. I really try to have some insulin ready to go when the food hits. A breakfast with egg and turkey bacon or sausage I extend for 1 1/2 hour. The timing of this second bolus is something I have FINALLY worked out. I do the second bolus at the end of the meal. Our day around here starts at 5:00 so my meals are earlier than most folks, thus the snack. I find that if I eat less than 20 carbs, my liver adds some undesired glucose. I have written about this before, know its weird, but this is what happens to me. Also a too late of a bedtime snack will get the liver to add some glucose or get rid of the insulin; Whatever the case, my numbers run higher than I want. I get up around 2 a.m to check bg since I have gotten in trouble in the middle of the night. No CGM here so lots of fingersticks. I think although we can learn alot from others, we also have to figure out what works for you. I still haven’t figured out how to exercise with all this. I do exercise and am quite active. My schedule is unpredictable so a temporary basal reduction 1 1/2 hours before activity is something I’m still working on. I’m sorry this was such a long post and I hope it makes sense. Best wishes.


Speaking for my pre-teen daughter, we’re counting protein at just over a 50% rate, that is 10g of protein to be metabolized into 5g carbs. We used to also count the fat at 10%, even if more involved, but Dr. Bernstein goes by 50% for protein only and we’re doing that too at this time. Even when doing the high-carb ADA-recommended diet we noticed a substantial effect of protein-rich meals, despite being told by the Yale endos that we shouldn’t count that, so I’m not sure if one should count protein much more differently with high-carb or low-carb diets. It’s probably that the amount of grams-equivalent glucose from protein in a high-carb diet is relatively so much smaller that it doesn’t affect the total bolus that much.
Timing is an important factor and meal digestion varies by the time of the day and type of food. We don’t have much experience but breakfast eggs seem to get metabolized fast, perhaps 1.5-2 hrs., fish for dinner perhaps in 2-3 hrs, and steak for dinner perhaps in 3-5 hrs. We expect the humalog to have run 85% of its act by the 2 hrs post dinner check (which is about 2.5 hrs since the injection) and that to cover the meal’s carbs and a theoretical portion of the protein, per the above. We try to target a certain bg for that time depending on the basal units as we rely on the basal to pick up the remaining protein from there on.
For example, if we check at 70 (well, that would be great) before dinner, and we plan to do 3 levemir for the night and a chicken-based dinner of 14g carbs and 40g protein, we would count the carbs to be covered by the bolus at about 21g, with about 13g left for the basal. So, at a rate of, say, 6.5g/unit (this varies much for us unfortunately) and assuming the levemir left past the first 2.5 hrs is about 85% and good for about 16.5g, we might want to be at 85-90 at the post dinner bg check. (We’re supposed to rise about 5.6 points per 1g carbs) Thus we would want to bolus for about 18g carbs, with about 2.5-3 humalog units.
Of course the dawn phenomenon may make it more challenging.

Just now getting back to this…was waylaid by that darned respiratory virus that was going around. Took me over a week to manage to get out of bed for more than a few minutes at a time.

So, thanks to you all for the information. It looks like I’m going to have to do some more learning. I can estimate carbs pretty well by now, but I have no idea how to count protein grams. If eating at home, I do have a scale that can read out in grams as well as pounds/ounces, so I guess if I stay out of restaurants for a while, I’ll be able to figure it out. But, frankly, I don’t think I’m going to be able to handle estimating carbs, protein in grams, AND fat. I’m just a bit math challenged since having a stroke several years ago, and that sounds too overwhelming. I’m just going to start by learning how to figure protein first.

It’s going to be a bumpy ride, I suspect, but I will persist, lol.