Insulin is a miracle drug that has saved the lives of millions of people with type 1 diabetes who can’t produce insulin on their own. Roughly one in three people who have type 2 diabetes are also on insulin—but do they all really need it?
If you are not producing sufficient insulin, injections may be your only option. However, I believe that insulin is overused in type 2 diabetes—and in some cases does more harm than good.
Let’s look at the pros and cons of insulin therapy for type 2 diabetes.
The Relationship Between Insulin & Diabetes
First, a little background. Insulin is a hormone produced in the pancreas. When glucose levels in the blood rise—as they do after your digestive tract breaks down the food you eat—your pancreas releases insulin. Insulin signals your cells to let glucose enter, where it is used to produce ATP, the energy that fuels your body.
Blood sugar then returns to normal and insulin secretion tapers off—unless one of these disorders throws a wrench into the works:
- Type 1 diabetes: This autoimmune disease damages the insulin-secreting beta cells in the pancreas and impairs their ability to produce insulin. Without insulin, glucose is unable to enter the cells.
- Insulin resistance: People who have this condition produce plenty of insulin, but their cells are insensitive to its signals. So, the pancreas compensates by releasing more and more insulin to get glucose into the cells. Insulin resistance is very common in people who are obese, inactive, and eat a poor diet. It is also the primary underlying cause of type 2 diabetes.
- Type 2 diabetes: The difference between insulin resistance and diabetes is to some extent a matter of degree. Over time, the cells become increasingly resistant to insulin’s signals, and the overworked pancreas can’t produce enough insulin to keep up. Blood sugar (and insulin) levels remain consistently high. That’s when you’re diagnosed with diabetes.
Insulin: A Wonder Drug for Type 1 Diabetes
Insulin truly is a wonder drug for type 1 diabetes. Before its discovery, people with this condition—most of them children—rarely lived a year or two beyond diagnosis. That changed in 1922, when Canadian physicians Frederick Banting and Charles Best, who had been experimenting with diabetic dogs, were asked to treat a 12-year-old boy in the terminal stages of the disease.
After trying injections of several extracts of beef pancreas, Drs. Banting and Best hit upon one that worked. The boy’s blood sugar fell from 520 to 120 mg/dL, and he rapidly improved, living another 15 years until he died of pneumonia at age 27. The Nobel Prize in Medicine was awarded for this discovery, which has allowed millions of patients with type 1 diabetes to live long lives.
What about type 2? Insulin injections for type 2 diabetes are generally initiated when oral diabetes drugs fail to achieve target blood sugar levels. Some doctors advocate earlier introduction or intensive insulin therapy, which requires very close monitoring and shots several times a day, on the premise that this helps stave off diabetic complications.
I agree that insulin is an indispensable therapy when patients develop severe insulin deficiency. Yet, I know from my decades as a practicing physician treating tens of thousands of patients with type 2 diabetes, that insulin is often used prematurely, inappropriately, and in excessive doses—and when it is, it can cause tremendous harm.
Type 2 Diabetes, Insulin & Weight Gain
Weight gain is a predictable side effect of insulin shots for type 2 diabetes. Insulin is so efficient at enhancing glucose entry into the cells that the cells often take up more glucose than is needed for energy. Excess glucose is converted to fat and stored in your body.
This is particularly problematic if you are heavy to begin with, as most people with type 2 diabetes are. Insulin causes even more weight gain, which makes blood sugar control all the harder. Doctors usually respond by increasing the insulin dose, which in turn drives weight and blood sugar higher still. Before long, patients are taking an obscene amount of insulin and don’t have a prayer of controlling their ballooning weight.
Patients are often chastised for not staying on their diets or exercising. Yet, their doctors never seem to consider the clear links between increasing weight and insulin use. I had one patient who gained 100 pounds in 10 years after starting insulin, as his dose was gradually increased to 100 units per day. I stopped his insulin immediately and started him on a diet, exercise, weight loss, and supplement program. It took him a few years, but he lost all that weight and never went back on insulin or any other diabetic medication.
Other Side Effects of Insulin
Other adverse effects of insulin therapy include:
- Hypoglycemia: The most serious side effect is low blood sugar, and it occurs relatively often, especially in older people and those on intensive insulin regimens. Recurring mild episodes have negative effects on the brain and cardiovascular system. Severe cases can cause falls, seizures, loss of consciousness, and even death. The CDC reports that hypoglycemia is one of the most common adverse drug reactions seen in emergency rooms in people over age 65.
- Heart disease: Several studies have linked insulin use in type 2 diabetes with an increased risk of cardiovascular disease and death. Both insulin-related obesity and recurrent episodes of hypoglycemia are associated with a greater likelihood of hypertension, lipid abnormalities, atherosclerosis, arrhythmias, and other cardiovascular conditions.
- Cancer: Research suggests that people with type 2 diabetes have an above-average risk of several types of cancer. Insulin resistance results in high levels of insulin, and among its other functions, insulin stimulates cell growth. Obesity, another problem for most people with type 2 diabetes, also increases cancer risk. The jury is still out, but insulin injections may well add fuel to the fire.
Talk to Your Doctor
Please understand that I am not advising anyone to avoid insulin. It is an essential therapy for some patients with type 2 diabetes. I am simply suggesting that you discuss the pros and cons with your doctor, because my clinical experience has shown me that the downsides of overaggressive insulin treatment are often overlooked.
Good blood sugar control is important, but it can also be achieved by other means, such as a focused program that includes weight loss, a low-glycemic diet, exercise, and targeted supplements. This safe, natural approach is not an overnight cure. It takes time and discipline, but it can be done—and the payoff is well worth the effort.