The Differences Between Type 1 and Type 2 Diabetes

I realize this might be old news for all you veterans of diabetes out there, but I thought this week I might write a little bit about the key differences between Type 1 and Type 2 diabetes. I thought this might be helpful for newcomers to our “Diabetian community” (and let me say that while I’m sorry you find yourself with the diagnosis, we’re happy to welcome you here), or as a resource to share with friends and family who can often have a hard time understanding the differences.

The understanding within the general public tends to be something along the lines of this: Diabetics can’t have sugar. That’s about it. So odds are pretty good that someone new to this disease is coming in with an idea that diabetes means you can’t ever have another cookie, but food without sugar is OK. And most of your friends and family will probably CONTINUE to think that well after you’ve gathered more information. Furthermore, the understanding of “Type 1” and “Type 2,” even among people who understand that there ARE two types, is often limited to age brackets — Type 1 is diabetes that starts when someone is young, Type 2 is what you get if you’re post-30. Or, more recently, Type 2 diabetes is linked solely to obesity, while Type 1 is…still diabetes for young people.


Two diseases, one name
An author of a study I once read pointed out that it’s rather unfortunate that we give the same name to these two diseases, because the mechanisms for how they work, AND the regimen for how we treat them, are very different. So then, without further ado, here is the lowdown on Type 1 diabetes, with Type 2 diabetes in a nutshell to come next week.

Type 1 diabetes is the result of an immune system malfunction. A virus moves through our body, usually without us ever even knowing it’s there. Our immune system springs into action to kill off the foreign cells, and the virus is defeated. But, there’s a problem. Our immune system made “sloppy” antibodies, and those antibodies (the foot soldiers of the immune system that search out and destroy the enemy virus cells) mistake our own beta cells for foreign virus cells. The beta cells, located in your pancreas, are the cells that produce insulin. And without insulin, we cannot process sugar.

You see, insulin is a hormone that moves through the blood, allowing sugar to be transported into our cells for life-sustaining energy. Without insulin, the sugar simply remains in the blood, and our “blood glucose” (how many milligrams of glucose are in each deciliter of your blood) climbs up and up and up until we lose consciousness (the blood being the highly complex and balanced stuff it is, blood glucose that is too far above or below the ideal range causes real problems — more on that later).

And we can’t just “avoid foods with sugar” to solve this problem, for two important reasons. The first is that our cells live on the glucose brought to them, so if there is no insulin in our blood, our cells will eventually starve to death, and unless you’re a zombie, that spells trouble. And second, MOST of our food is metabolized into blood glucose. An apple, a cup of Cap’n Crunch cereal, and half a cup of brown rice might all contain around 30 grams of carbohydrates. The ice cream is mostly refined sugar, the apple is fruit sugars, and brown rice is unrefined carbohydrate. But they will ALL be converted into glucose (the type of sugar the blood processes to the cells) and delivered to our cells. Even protein can eventually contribute to our blood glucose. The difference is that the brown rice will take more time to be “broken down” in the body, and that means the sugar from THAT carbohydrate takes longer to reach our blood, while the refined sugar in the cereal takes very little time to hit the bloodstream. This is, of course, why we don’t treat hypoglycemia with brown rice — when our blood glucose is LOW, we need something that will reach the blood quickly.

Getting back to inner workings of Type 1, we now see what happens to cause the disease. 1) Our own immune system mistakenly kills off the insulin-producing beta cells; 2) the lack of insulin means sugar can’t move from our blood into our cells, meaning that our cells have no access to life-sustaining glucose, AND 3) the balance of our blood is lost, eventually leading to loss of consciousness. So now, we have to start injecting synthetic insulin when we eat, both to keep our blood glucose as close to the target range as possible (in non-diabetic people the range is generally between about 70 and 140 milligrams per deciliter), and to get that glucose to our cells!

Along with this synthetic insulin comes a whole host of new responsibilities! We now have to correctly calculate how much insulin we inject to match the amount of carbohydrates in our meals based on a “sliding scale” (example — taking 1 unit of insulin for every 15 grams of carbohydrate in the meal). If we miscalculate with too much insulin, our blood glucose will fall too low afterward, and we will have to correct it by ingesting quick-acting sugar, like juice, soda, hard candy, or glucose tablets. The typical response is to take 15 grams, wait 15 minutes, test, and then consume another 15 grams if our blood sugar is not back in target range. If our blood glucose is VERY low (less than 50, for example), we might take 30 grams initially. The exact ratios differ for everyone and are set with the help of your health-care team.

If we take too little insulin (or eat too much — either because of a lapse in judgment or we simply miscalculated), we might run high after the meal. Our blood glucose can get pretty high without immediate symptoms (for example, you might lose consciousness from a LOW blood sugar around 20–25, which is only about 60 below the target range, but you would have to climb into the 900s or even higher to pass out from a high blood sugar — about 700–800 above the target range!), but high blood sugars are what contribute to long-term complications, so it’s important to avoid them. If we are high, we correct with extra insulin, again based on a scale determined for us with the help of our health-care team.

This is all just the tip of the iceberg — that’s why this website can fill a solid six to seven weekly blogs with information and it can all be USEFUL! There’s just a lot that goes into managing this disease. But hopefully it can provide a good starting point for understanding exactly what it is that’s going on inside your body so that you can feel better informed. Next week, I’ll run through Type 2 diabetes, and then examine some of the areas of overlap, like the effects of activity, sleep, and weight on living with diabetes.

Short bursts of intense exercise may be effective for preventing and treating Type 2 diabetes, according to a new study. Bookmark and tune in tomorrow to learn more!