Dispelling the Myths of Insulin Therapy

In my position as a pharmacist and certified diabetes educator, physicians often assign me the task of starting their patients with Type 2 diabetes on insulin therapy. Unfortunately, in most situations, insulin has been presented to these patients as a last-ditch treatment option, after target glucose goals have not been achieved or maintained with lifestyle modifications and other therapies.


Not surprisingly, I encounter people who are upset at the news that insulin is now necessary. Others feel anxious or overwhelmed by the prospect of fitting insulin into their lifestyles. Many people believe that insulin causes the complications of diabetes. Here is some information to dispel some of these myths about insulin therapy:

Myth 1: “It’s my fault I am being put on insulin because I didn’t do what I was supposed to do.”
People with diabetes often view the switch to insulin therapy as sign of personal failure in managing their diabetes. Insulin may be perceived as a punishment for failing to exercise, eat properly, or take their medicines. However, due to the progressive nature of Type 2 diabetes, people should expect to eventually require insulin therapy — this is due to the diabetes running its natural course, not to failure on their part.

It is inevitable that the insulin-producing beta cells of the pancreas will deteriorate over time, resulting in insulin deficiency. In other words, the pancreas cannot keep up with the body’s need for insulin no matter what you’ve done to manage your diabetes. Accordingly, insulin treatment is a normal and effective way of replacing the body’s insulin. Think of it as a form of “hormone replacement therapy.” The goal of all diabetes treatment is to find the right combination of treatments to provide the best blood glucose control while minimizing side effects — insulin is merely one of those options.

Myth 2: “Insulin injections hurt.”
Most people are surprised by how little an insulin injection hurts. With the small, fine needles available today, insulin injections are virtually painless. Insulin is injected into the layer of fat below the skin where there are no pain receptors. In fact, most people tell me that the finger pricks used to measure their blood glucose levels hurt much more than their insulin injections.

Myth 3: “Now that I am on insulin therapy, I will have more episodes of low blood glucose.”
Although some degree of hypoglycemia, or low blood glucose (typically defined as a level below 70 mg/dl) may occur in people using insulin, severe hypoglycemia is rare and has been shown to affect only about 0.5% of people with Type 2 diabetes. You can learn how to prevent, recognize, and treat hypoglycemia, therefore avoiding severe episodes.

Early symptoms of hypoglycemia include shakiness, nervousness, sweating, and confusion. People with diabetes should always carry a source of carbohydrate with them, along with a blood glucose meter to check glucose levels when any of these symptoms occur. Treatment is usually 15 grams of carbohydrate, examples of which include 3 or 4 glucose tablets, 4 ounces (1/2 cup) of fruit juice or regular (non-diet) cola, or 5 or 6 pieces of hard candy. Blood glucose levels should be checked again in 15 minutes and, if levels are still low, the steps above should be repeated until the glucose level is 70 mg/dl or higher. Strong evidence has demonstrated that the benefits of achieving good blood glucose control outweigh minor episodes of hypoglycemia as long as these episodes are not too severe or too frequent.

Myth 4: “If I am placed on insulin therapy, I will gain weight.”
Some people with Type 2 diabetes may gain weight after starting insulin therapy. However, often this weight gain occurs due to improved blood sugar control. Uncontrolled diabetes causes people to lose weight because glucose cannot get to the cells in the body. When insulin is introduced, glucose can be absorbed from the calories eaten, leading to some of the weight that was previously lost being regained.

To minimize weight gain following the initiation of insulin therapy, people with diabetes should make healthful food choices and get regular exercise. The good news is that weight gain tends to level out as insulin therapy continues, and the weight gain may be temporary. Ultimately, the benefits of good blood glucose control will reduce the risk of complications and should take priority over the concerns about weight gain.

Myth 5: “Insulin causes complications like blindness and kidney failure.”
Part of the reason behind the “negative image” of insulin is that physicians have historically used it as a warning to keep their patients motivated and focused on other therapies. It’s no wonder that people who try their best, but inevitably need insulin therapy, often feel guilty.

Physicians commonly delay starting insulin due to their own hesitations about the treatment. Some of these include a fear of causing low blood glucose or a concern that their patients will not adhere to an insulin regimen. The result is that insulin is often added to therapy too late in the course of diabetes. The reality is that people do not develop complications from being started on insulin, but rather, they develop complications from being started on insulin too late. Insulin actually reduces your risk of getting complications. Adding insulin to your treatment can improve your control and result in fewer complications than you would have had otherwise.

Hopefully, these myths about insulin will go away as doctors begin insulin therapy sooner rather than later and people with diabetes become more educated about insulin treatment. So if your physician tells you its time to add insulin to your regimen, just remember, diabetes is a chronic, progressive illness. The longer you’ve had Type 2 diabetes, the more likely you are to need insulin. Insulin can provide improved blood glucose control and slow or prevent the development of complications.

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  • Dave Huntsman

    You don’t cover any legal or regulatory issues of going on insulin. As a (former) private pilot who would like to fly again some day, I understand that once you’ve gone to insulin, you’re banned from flying. True? How about any other machinery or occupations?

  • Mark Santos

    Hi, Dave. Was true — until the early ’90s when restrictions were lifted due to medical advances in diabetes management and a tougher stance on discrimination against people with disabilities. Diabetes is now a ‘certifiable medical condition’ for Canadian pilots (certain individual criteria have to be met), allowing pilots on insulin to fly.

  • Jeff

    In the US, you cannot get a CDL license without a Dr approval once you are on an injectable insulin. I was looking into getting my CDL as a possible second income a couple years back. I found out that no good doctor would sign off on such a thing since it puts them liable if something were to go wrong.

    It does make me wonder how many out of control diabetic truckers are on the road today because of such a law…

  • Tom Whitcomb

    Is there any correlation between insulin and the probability of having Dementia or Alzheimers?

  • Betsy Carlisle, PharmD, CDE

    Dave – I would refer you to the website of the Federal Aviation Administration. Search for “FAA Protocol for Pilots with Insulin Controlled Diabetes.” It requires a decision by the FAA and strict monitoring prior to takeoff and while in the air.

    Jeff – I would refer you to the Federal Motor Carrier Safety Administration website. Search for “diabetes exempt application.”

    We are definitely making strides in both areas for people with diabetes.

  • Onoosh

    For me, “Myth” 5 (“Insulin makes you gain weight”) was not mythological. I was initially diagnosed as a Type 2, went on insulin at diagnosis, then just oral meds…but continued to lose weight and watch my BG go up anyway.

    That’s when I persuaded my doctor to do antibody testing, and–voil√É !–I have LADA, a.k.a “Type1.5,” creeping type 1. Insulin (Levemir) again. I gained twenty pounds in two months. I am more active now than at diagnosis, we eat VERY healthily (vegetarians, extremely low carb) but the twenty pounds is still there: right around my middle. I haven’t gained any more, but I don’t like the weight gain one bit.

    Any suggestions besides what (water aerobics, yoga) I’m already doing? Suddenly developing diabetes is depressing enough without looking in the mirror and saying “Yucchh!” ūüôĀ

    P.S. : My last A1c was 5.4. Pretty good control, I’d say.

  • Mel

    Last time I saw my endocrinologist, he told me something very disturbing. He told me insulin is a form of a growth hormone. This is generally why people start to gain weight when they start to use higher doses of insulin. Which, coincidentally, matched my case. But the disturbing part is, he said, if you have some malignant cells starting to mass-up (i.e. cancer) taking high doses of insulin, speed up the growth of these cells as well as non-malignant ones.

    Can anyone shed some light onto this subject ? I am type-2 and overweight. My calorie intake is hardly above 1500 per day. And I am an office worker at age 50, which should put my daily caloric intake need around 1750. Yet, I can not make even a minor reduction in my weight.

  • Judy

    Your statement about weight gain is really deceptive. I was exercising and watching what I ate when I need to go on to insulin. In the next 6 months I gained over 100 pounds. I had some of the best Endochronologists working on my case and they couldn’t stop the weight gain. My diet was cut at the end of gain to just 600 calories. I have neither gain nor loss since and that was years ago. I have a low self esteem now that I am so large. I would tell anyone try to avoid insulin at all costs.

  • Terri

    Ugh on #4…weight gain!

  • Joe

    Uncontrolled diabetics lose weight because their cells are starving. Without enough insulin (or if the patient has insulin resistance) much of the glucose remains in the blood and is eliminated in urine instead of being absorbed by the cells.

    When a patient is placed on insulin therapy, the cells once again absorb glucose and weight gain results if the person’s caloric intake excedes calories burned. The only way to avoid this is diet and exercise. The good news is you’re no longer starving, and the excess glucose isn’t damaging your system because it’s going where it’s supposed to.

  • Onoosh

    Diet and exercise: unless you count not gaining any MORE weight than the twenty pounds I put back on in the first two months on insulin, that doesn’t provide any help for a “Type 1.5″/LADA diabetic like me.

    Don’t misunderstand me: I’m grateful that insulin exists, since I was very sick when I was diagnosed, and give myself my shots, which ARE less painful than sticking my fingers, religiously…but I wish someone would come up with a solution to the weight gain phenomenon.

    I don’t see any new, helpful suggestions, let alone answers, here for those of us whose life as diabetics is complicated by this mysterious weight gain. Oh, I’ll take it in preference to neuropathies or an amputated foot, but if I had a choice, it would be “e.) none of above.”

  • Kate

    I lost weight on insulin. After many years on oral meds, I asked my doctor to prescribe insulin. Within 2 months, I lost 15 pounds without trying. Finally my body could use the carbohydrates I was eating and I was no longer hungry. I’ve been on insulin now for 5 years and have experienced no weight gain, and that incredible hunger I used to battle no longer exists. I do think overdoing carbohydrates causes hunger rather than stopping it. I was trained to vary my rapid insulin dosing to the number of grams of carbohydrates in my meal, taking into account the amount of exercise I was doing. I am very careful not to go low (boy was this stressed by the CDEs). I am very happy to be on insulin.

  • Onoosh

    So far, I’m only on long/slow acting insulin. I count carbs. I eat no sugar, bread, rice, pasta or potatoes, except for a tiny taste of my husband’s sweet potato. I exercise. I test frequently. My BG is well-controlled.

    I’m happy to be on insulin: but I’m not happy about the rapid weight gain, and glad it has stopped.

    While I agree about the relationship of carbohydrates to hunger (that was something I learned years ago at Weight Watchers, of which I’m a Lifetime Member) hunger is not the problem. The mysterious and recalcitrant twenty pounds–which happened, I repeat, when I began insulin again–is what irritates me.

    I wish someone could give me a reasonable answer to this phenomenon that fits my diabetes, and a way to deal with it. So far, no luck.