Low Carb, insulin needs and size

Hi all

I am 40, type 1 for 20 years. I am on insulin pump. Few years back had anxity problems due to low blood sugar anxity. At that point i reduced my food intake a lot. Thanks to help managed to get trough this and started eating a lot more (put on 50 pounds in 3 years), I am now stable. My diet is somewahat low card (60 to 100 per/day). I am a big guy. 6.3 feet. SO my ideal weigh is around 220-230.

My question. I am on about 40 units a day for basal (around 1.5u/hr on pump). I find this is quite hight. I dont do sport since covid as all is closed here. But talk an hour walk in forest each day.

My question: and of you t1 and is 40 units/day basal high for a size like me? I know it varies a lot but just wandering. As of now i am thinking of upping it a bit more as my 2 hours post meal is ok but then takes to long to go back down if i dont take a walk or some light excersice after eating.

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Hi @GTOURRET1 ,welcome on board!
I’m glad to hear that getting through anxiety of hypos has helped. I dreaded hypos, hated them, and as a result for many years I let my sugars run high which left me with HbA1C in the mid 8s. Only after getting the Dexcom and learning to trust it has that improved and my A1Cs have been in the low 6s. Some complications to be expected.
Everyone has different basal insulin needs and the insulin required to deal with what they eat. I don’t think it’s possible to compare and measure.
I’m 5-10 and 155 lbs and fairly active. I have 0.67 u/hr. I eat 150-160 g of carbs a day and the ratio is about 1:9.5 so total daily insulin is about 35 u.
But I have to exercise after eating or my insulin doesn’t “work”. It’s kind of crazy to me that I can have a 70 carb supper after waiting 20 minutes from bolus and quite often my blood sugar just goes up an up. Then ten minutes on the bike or treadmill and it drops like a rock! I would rather exercise than add another few units. And sometimes, for no good reason, the glucose level stays perfectly flat. In that case, if I exercise I need to drink orange juice or something.
Oh. . To answer your question, I suspect that 40 units is right as long as your monitor is giving you a tracing that you like. Even if, like me, you need to exercise a bit to keep it there.
Other people may have different experiences.

Oh, and my own insulin daily requirements dropped about 10% when I went on the pump.

Hi GT, welcome to the site.
I am also 6’3 and I and 210 lbs. I want to be under 200.
I think 220-230 is a lot for your height unless you have a lot of muscle mass.
I was always lean when I was a kid all the way through to my 30s. I was diagnosed at 155 lbs when I was 21.
I’m 55 now.
I have pretty much always used about 50-55 units a day. Weather on multiple injections or a pump. Maybe in the mid 40s when I was playing sports.

Everyone is different my basal is about 1.2 per hour. And I bolus around 25 a day. As I get older I find that fat raises my insulin needs more than carbs do. Therefore I don’t do low carb.

The rule of thumb is to have that basal and bolus 50/50.
For me it just worked out that way to be pretty close.

There is no normal really, it’s just what you need, you should take.
I’m on a pump and I stay in the high 90% range most days.
Cgm has helped me a lot with the anxiety of going low.
I used to never go to bed if I was under 130 or so.
Now I’ll go to bed even if I’m 80 because I know my pump will adjust, and alarm is I drop out of range

Exercise after meals is key for me. Just a walk or hike takes care of it. I don’t need to break a sweat that often


I agree with @Timothy I am 6’1" and weigh around 195, I am trying to get to 185. My basil rate is around 32U per day. I do not subscribe to a low crab diet so my insulin requirements are little higher. However, there is no “normal” for my age and weight. A far better thing to look at is how much total insulin you are using each day.

I measure this only in terms of what I typically use, so if in a regular day I used around 60u (I am usually somewhere between 50 and 60u) I know I have hit the mark pretty well. If on the other hand I use 45, or 85, well I should be looking into it.

By way of comparison if I have moved more than 5u then I know something is off and if I do not know why I figure it out,



Welcome to TuD, @GTOURRET1! You ask a question that is difficult to answer due to its complexity. Managing weight with diabetes is a hard one. If you are overweight (compared to your historical weight), the amount of insulin you take does play an important metabolic role in your ability to lose weight.

From my perspective as a long-term T1D who has successfully lost a significant amount of weight and kept it off, I have learned a few things. The reason that carb-limited diets have been effective in losing weight is that the level of insulin in the blood plays a crucial role.

When insulin levels are above a certain threshold, your body will not use stored fat for energy. It’s just not metabolically possible. But, when insulin drops (or less is taken due to diabetes management) below that threshold, then the metabolism permits the body to use stored fat for energy.

People who eat a carb-limited diet, especially those who regularly use some form of time-limited eating, can lose excess weight. And when you weigh less, you need less insulin. It can be a tricky process to manage but it can be done. There are many T1Ds like me who have lost significant amounts of weight while reducing our total daily dose of insulin in the process.

Everyone’s unique insulin needs vary from each other as well as vary from day to day in themselves. Yet you need to understand that consistently adding a little too much insulin so that you bring your blood sugar into range can easily lead to weight gain and also prevent any weight loss as I described above.

I suggest you read up (also watch some YouTube videos) on the topics of weight loss in diabetes, carb-limited way of eating, and intermittent fasting. Your knowledge of these topics, I consider as the fundamental human software needed to manage diabetes well when your body makes no insulin.

This is not a short-term challenge, so it will work to your advantage to look at this problem in a longer term perspective. Measuring success in months and years instead of days and weeks is the preferred state of mind. Good luck! Please ask any follow-up questions you may have. Many people struggle with this exact same challenge.