To what degree are insulin use and weight gain intertwined?


I'm Jamariel, an 18-year-old type 1 diabetic. I'm currently taking both rapid-acting and long-acting insulins, Humalog and Lantus. Recently, I've been much more vigilant than I ever have been about controlling my sugars, and of course, that leads directly to more insulin consumption.

Right now, my meter says my averages (7-day, 14-day and 30-day averages) are 95, 90 and 90, respectively. I'm averaging 200 carbs a day and around 25 units of rapid-acting insulin a day, up from my previous average of 3.

However, with this increased insulin usage has come an unfortunate weight gain. Within the last month, I've gone from 160lbs to around 175-ish (I'm 6ft tall). While this is within normal weight range for my height, to gain so much weight in such a short period of time is really concerning. Is this normal?

Also, how can I avoid gaining even more weight and facilitate getting back to my natural weight of 160 without cutting my insulin doses?

Thank you,


hi Jay!!
Nice to hear from you ;)
I am sorry about your weight gain. From what i know and have experienced, the weight gain can often come from insulin not matching your needs, especially if you overdose it and then have to eat low treats afterwards. basically, your insulin in your body hasn't increased, your pancreas just has stopped producing its own and therefore you need to give more from the outside, but the amount of insulin in your body stays around the same.
Are you having a lot of lows?
hope i could help you to some extend

Unfortunately, this is normal when you're taking insulin and sometimes the price that is paid for improved control. Insulin is a fat storing hormone, so the more you take the more chance you have of gaining weight.

What works for me is low or lower carbs and excercise. The simple explanation is the less carbs you consume the less insulin you need to cover those carbs and the less weight that is gained. Exercise is great for improving your control without having to add more insulin. It improves your insulin sensitivity.

I also have the other issue in trying to attain super tight control and that is too many lows which require more calories to be ingested which can lead to weight gain.

It's part of the balancing act we all face everyday. Good Luck!

Is it possible... your previous weight of 160 pounds was the result of way too little insulin and way too high bg's? You say just it was previously just 3 units of fast acting a day.

Long term uncontrolled T1's tend to weigh below average.

As Tim mentioned, you may be "rebounding" form being underweight from the high bg's. High bg means that your body isn't getting the fuel it needs, and it turns to stored fat (and eventually muscle if necessary) for fuel. And of course there is the constant peeing. It could very well be a combination of regaining lost water weight and weight lost due to expelling the "fuel" in the peeing process. I would just watch what you are eating, tweak your I:C ratio and take it from there.

When I was first (correctly) Dx'd, I was 105 lbs (I'm 5'6"). Obviously even for me - a ballet dancer - that was underweight. Unfortunately, the hospital staff wouldn't take into consideration that my working weight was 115 and I couldn't get released until I was 130. It took a while for me to get back to working weight - and I wasn't able to earn my pay due to that weight. I finally found an Endo (who knew the ballet world) who helped me and didn't pooh-pooh my concerns or send me to the eating disorder people.

To answer your question more directly Jay, insulin is a powerful anabolic hormone. Without sufficient insulin production, it's impossible to build up stores of fat, glycogen, or even build muscle.

In a situation where you are not producing sufficient amounts of insulin, where dietary source of glucose cannot be used, the condition progresses. Any source of glucose from diet, or gluconeogenesis, or glycogen breakdown from the liver, just result in higher and higher blood sugar. Your cells are starving, so more hormones causing more gluconeogenesis, more glycogen breakdown, more fat breakdown, and more protein breakdown are released. Eventually your cells are relying completely on fat and, literally, cannibalizing the protein from your muscles to fuel themselves. Your blood sugar is skyrocketing, your spilling excess glucose from the blood into urine, and you're going into ketoacidosis because of the huge amounts of protein and fat being metabolized.

Those are the reasons why one of the classic symptoms of T1 diabetes is dramatic weight loss over a short amount of time.

Now, go onto insulin treatment, and you immediately reverse the condition. Cells can use all sources of glucose for fuel again so you stop releasing antagonistic hormones that cause the breakdown of fat and protein. Blood sugar drops because insulin allows you not only to immediately use insulin, but also signals the storage of excess glucose as glycogen and fat instead of spilling it out into urine.

For most people, as posters here have suggested, this results in a fairly rapid weight gain once you start insulin treatment. Now, you will have to manage your diet, activity level, and insulin dosing to match your needs.

The thing you don't want to do is simply cut back on your insulin dosing with hopes that your weight will just drop back down. If you don't balance your carb and protein intake to match, you'll just end up with high BGs again.

It's a dance Jay. What you'll find in this forum are the many ways that PWDs on insulin can successfully find that balance. Whether it's a lower carb diet, lot's of exercise, or some combination, it's what all of us struggle with.

Oh, forgot to congratulate you. Those are great BG numbers!

It's very unlikely. Throughout high school, I've always weighed 160, more or less. That's part of the reason why this sudden weight gain has me so concerned.

I jog daily. I guess what this boils down to is that I need to consume less carbs overall. Sounds good to me lol Means better sugars. :3

Hey Swiss :)
I have been having a lot of lows, but I don't usually eat to bring my sugar back up. I generally take 2-4 glucose tablets, which only have about 15 calories per tablet and 4 carbs per tablet.

Wow, that's a unique perspective, very interesting!

When I was diagnosed about a year and a half ago, I weighed around 130 (I was still 6'0). Throughout the span of the past 5 years, with the exception of my I've always been around 160lbs, give or take. That's why it concerns me to this degree that I've gained so much weight in so little time, and that that coincides with my increased insulin usage.

Ahhhhh, ok! I understand now. Thank you very much for that detailed explanation. It seems I need to cut back on my carb intake and thereby reduce my insulin intake.

Thank you very much!

Also, you would want to conceptualize your insulin dosing as a ratio so if say 8G of carbs/ unit of insulin is pushing you down, maybe 9 or 10 (or 9.3…?) will work more smoothly?

Jay, others have explained the details well. Simply put, you're eating too much for your activity level.

Hook yourself up with an app like MyFitnessPal poor similar to help you get your nutrition balance figured out. To a mild degree you've been operating like a diabulinic, passing out sugars rather than laying on far.

That would probably help. I'm a bit reluctant to change my carb ratios at all right now though. My endo wanted me to keep this ratio (24 units of Long-acting combined with a 1:15 carb ratio) for a period of time before I try making any more changes, just so I can actually see whether or not it's working for me.

The diabulimia thing is extreme lol

I'm not diabulimic, but I eat what I want. Normally, my weight isn't a concern. In this case, the amount of weight gained coupled with the time frame is what concerns me.
Anyways, the first part sounds about right. I do tend to eat like, well, a teenager. I've cut back on simple carbs and carbs in general. I eat smaller portions and jog whenever I can. So far so good. I'm at 170 now.

i'm not sure what you mean by going from 3 units to 25 units, is that fast acting? thus, you must be eating more, no? or, is that your basal? if you've gone from 3 units of fasting to now using 25 that means you must be eating a ton more, are you on a pump? if you eat more, you'll gain weight. if you truly were not giving yourself enough insulin for meals (i.e., only 3 units) then yeah, your BG's must have been sky high, were you doing any correcting with those mere 3 units? Did you ever go DKA? how did you manage your meals, did you not eat? if your I:CR is 1:15 then you were only eating 30 grams of carbs per day (3 units) and now you're eating 200 grams? Also, if your basal needs are 24 u/day, 25 units of fast acting is about right. not sure how you got by with only 3 units/day?

That was a few months back. I wasn't managing my diabetes at all. My a1c was 11, I saw more 300+ BGs than not, and I was eating as if I wasn't diabetic.

The reason my average administered insulin went from 3 units to 25 units (Humalog) is not because I started eating more, but because I actually started bolusing for what I ate.
Also, no, I never went DKA, though I was typically ALWAYS hyperglycemic.

Sounds like you're doing a great job at getting both your diabetes and your weight under control. Good job, Jay!