If type II diabetes is manageable with diet alone, why is type I diabetes not?


My understanding is that most Type II diabetics have a pancreas that isn’t producing ENOUGH insulin, whereas Type I diabetes have a pancreas that isn’t producing ANY insulin whatsoever.

But insulin is needed in response to blood sugar, which would come from carbs.

Type II diabetics can control their diabetes by eating healthier and most notably they will not need insulin if they don’t eat any carbs, since protein and fat doesn’t raise your blood sugar.

Isn’t the same true for Type I diabetics? That carbs raise blood sugar, so abstaining from carbs prevents your blood sugar from going up? And you don’t need insulin to RAISE your blood sugar if it’s too low, you can use a controlled amount of sugar to bring it back up?

I know diabetic ketoacidosis is MORE of a concern for Type I diabetics but I don’t fully understand what that is either. I’ve heard people say that the keto diet is okay for Type II diabetics but dangerous for Type I diabetics. Why is that?

In: Biology

I was diagnosed with T1D 4 years ago, when they explained the differences to me in the hospital what I understood was that type 2 is just overloading your pancreas so that if you were to “give it a break” by eating healthier it can regain most of its control again. Whereas type 1 is an autoimmune disease where your body attacks the cells that produce insulin. With type 1 your body can’t raise or lower it’s own blood sugar so you have to inject insulin when your sugar is high depending on how high you are. For when it is low you can eat a glucose tablet or anything with about 15 grams of carbs in it to raise it back up. If your blood sugar is to high for to long you go into ketoacidosis. Your blood becomes thicker because of all the sugar in it, becoming almost like engine oil for a car instead of being like water. The thicker blood can do some serious damage to small blood vessels like in your eyes and can damage your nerves in your extremities, and it can make your immune system slower so infections anywhere can be super dangerous. Hope I helped answer your question.

The issue is not getting sugar into your blood, the issue is getting that sugar from your blood into your cells and regulating the amount of sugar in your blood.

In healthy humans, your pancreas secrets insulin into the bloodstream. Insulin is a hormone that enables sugar (glucose) to enter your cells. By doing this it also lowers the amount of sugar in your bloodstream. As your blood sugar drops, so does the amount of insulin that is secreted. It’s a very self-regulating cycle.

Type I diabetics produce little to no insulin. This means they cannot get sugar from their blood into their cells (which need it for function). When your body cannot get the energy it needs from sugar, it begins to break down stored fat instead. This process causes a buildup of acids in the blood called ketones which can have harmful effects on things like your liver and kidneys. For healthy people (like those on the keto diet) breaking down fat instead of sugar wont generally lead to dangerous levels of ketones.

Type II diabetics are either resistant to insulin or don’t produce enough. Basically, their insulin process work’s but just not *that* well. They can’t get quite enough sugar out of their blood and this increased blood sugar in turn causes more insulin to be released and eventually the body can’t meet the required insulin demand. They’re not able to regulate things properly.

Not exactly. Many type 2 diabetics produce enough insulin in theory, but they’ve developed an insensitivity to it so they can’t use it properly. Some don’t produce enough. Eating only minimal carbs can help to reset their body in some cases, but not all, to be more sensitive to insulin.

As for type 1 diabetics: eating no carbs at all is not a practical or sustainable way to live. It’s a very difficult diet to maintain, but also, since they don’t have any insulin, if they eat any carbs and glucose gets in their blood, it will cause damage. People on ketogenic diets typically eat at least a little carbs, which is fine for them but dangerous if you have type 1 diabetes. And the body isn’t meant to live all the time purely via ketosis. The epileptic people who use a ketogenic diet all the time still have some carbs. Without insulin, a type 1 diabetic’s situation can turn bad very quickly and they can get ketoacidosis and die. It’s straining the body to the limits of safety for no good reason.

I only know of one person who has done this for a significant length of time, and that’s Elizabeth Hughes Gossett, who developed type 1 diabetes in 1918, before there was insulin to treat it. By keeping her on a low calorie ketogenic diet, she managed to live for a few years, though she was skeletal and didn’t grow (she was a child at the time and should have grown several inches). She was close to starving to death for quite awhile—she wasn’t thriving. But it kept her alive until 1922, when scientists created a method of jnjecting insulin to treat type 1 diabetics and then she could start doing that and she gained weight and could start to live a normal life again.

Diabetes mellitus involves problems with insulin. Insulin is a hormone that, among other things, moves glucose from the blood to inside cells. It is a very fine balance. If the cells dont have glucose, they can’t do much, they run out of energy and bad things happen. Worst case scenario, you die. So moving the glucose inside the cell is good. Except you need to have enough in your blood that the cells that need it can access it when they’re under stress. So low blood glucose means that the cells that need it have no glucose to access. Worst case scenario, you die. So insulin has a very important job helping to regulate blood glucose levels and making sure cells can access glucose. Without insulin, the glucose just stays in the blood and can’t get into the cells.

Type 1 diabetes, also known as insulin dependent diabetes, is caused by an autoimmune condition where the cells in the pancreas that produce insulin are destroyed. So you end up in a scenario where you have no insulin. The blood glucose levels go up and up and you can’t do anything with it. Your body has to start breaking down muscles and fat into fatty acids and use that as an energy source instead. You produce ketones, go into a state called diabetic ketoacidosis and, worst case scenario, you die. The only way to treat type 1 diabetes is to replace the missing insulin. Diet alone wouldn’t work as you would still be unable to use the glucose, and if you cut out glucose and only ingested fatty acids you would just cause diabetic ketoacidosis.

Type 2 diabetes, or insulin independent, is different. It is caused by the body becoming desensitized to insulin. It has genetic and dietary components to it, but an oversimplification is that the insulin is there, but it’s just not working as well. But some insulin does work, and the cells are usually getting enough glucose, there just either isn’t enough for the level of glucose in the blood or the body has had high levels of insulin for so long it isn’t as effective. Blood glucose levels do go up but your body is still producing enough insulin that your cells can absorb the glucose and carry on doing their job. Therefore diet is the first point of call. Eat well, reduce your blood sugar levels and hopefully reverse the desensitization to insulin. Other times medications such as metformin can make cells more sensitive to insulin again, or there are other drugs that lower blood glucose levels or increase insulin secretion.

That is is the basics. In advanced T2DM, there is often a need for insulin as the drugs and diet aren’t working. There may be a need for a huge amount of insulin as the body is so desensitized to it. There are also mixed conditions where there are both mechanisms causing diabetes going on.

TL;DR: insulin helps your body use glucose and keep your blood glucose levels in a normal range. In type 1 diabetes, there is no insulin so even if you dieted you couldn’t use the glucose that was there. In type 2, there is too much glucose for the amount of insulin you produce, so diet helps lower your blood glucose levels.