Diabetes, also known as diabetes mellitus, is a hormonal disorder involving an endocrine gland, the pancreas. It can also be an autoimmune disorder or develop autoimmune characteristics during the progression of the disease. The complications of diabetes can affect other organs and systems of the body as well—diabetes can damage the kidney, the cardiovascular system, the nervous system, the eyes and the brain. Perhaps most importantly, however, diabetes is a disorder that can be prevented, treated…and reversed in some people!
What is Diabetes?
As mentioned, diabetes is a hormonal disorder—in diabetes, the hormone insulin is either not produced by the pancreas, not enough is produced or the insulin that is produced does not function properly. Insulin is a hormone, that among other functions, allows all the cells of your body to use glucose, a sugar that is obtained from the food you eat. Glucose is the primary source of energy for the cells of the body, and when the cells, organs and tissues of your body cannot obtain the fuel they need in sufficient quantities, all of the cells, organs and tissues of the body “feel the pinch” in varying degrees. The complications of diabetes can be traced back to the effect of high levels of glucose (sugar) in the blood—these levels are high because the sugar derived from food can enter the blood as it is supposed to—but once in the bloodstream, it is stuck there because the cells, tissues and organs of the body don’t respond to the signal from insulin.
More about Insulin
We mostly think about insulin as a hormone that controls blood sugar and this is true. Insulin signals cells that it is time to transport blood sugar out of the blood and into the cells, where the sugar is used as fuel to run the biochemical reactions in the cells—something that goes on 24/7. Insulin also has a number of other functions—and understanding these other functions can clarify why some of the complications of diabetes occur. Insulin also acts on the liver to increase the amounts of glycogen—a storage form of glucose to be used when needed. Insulin also plays a role in the way fats (triglycerides and others) and proteins are used, the way muscles are repaired and how minerals are handled by the kidney.
In healthy individuals, insulin is stimulated by increasing levels of blood sugar that usually occurs after a meal. The carbohydrates and other nutrients are digested in the stomach and small intestines and the newly digested sugars leave the intestines to enter the blood. These rising levels of blood sugar is detected by the beta cells of the pancreas which are then stimulated to produce insulin. The insulin stimulates the transport of the sugar from the blood into the cells and tissues and the lower blood sugar levels then tell the pancreas that it should stop producing insulin.
What Causes Diabetes?
The simple answer is that we don’t completely or precisely know what causes diabetes, though the “Western diet” that consists of high levels of processed foods that are high in sugar are definitely implicated. We do know, however, that a number of different factors play a significant role in diabetes. The role that these risk factors can be variable and it is important to remember that having one or more of these risk factors at play does not mean that you are somehow “destined” for diabetes. Some of these risk factors can be changed—and that means that you can have much more control over the disease than, for example, someone with another disorder. The factors that you can’t control are:
- A family member has diabetes
- You come from an ethnic background that includes African, Asian, Hispanic or Native Indian.
- An injury to the pancreas, the organ that produces insulin. This injury can be due to infection, a tumor, inflammation, an accident or surgery.
- Age—the older you are, the greater the risk.
- Disorders such as autoimmune disease. Having one autoimmune disease, where the body’s immune system mistakenly reacts to your own cells and tissues, increases the risk of having another autoimmune disease—and there are forms of diabetes where autoimmunity plays a role
On the other hand, there are factors that you can control, at least to some degree. These include:
- Stress levels—this includes physical, mental and emotional stress
- Disorders such as high blood pressure, high blood cholesterol and triglyceride (fat) levels
- Alcohol use—the more alcohol you drink, the greater the risk
- Smoking—the longer you smoke, and the more you smoke, the greater the risk
- Pregnancy—pregnancy can increase your risk of a form of diabetes known as gestational diabetes and this puts you at greater risk for the more common forms of diabetes.
What are the Types of Diabetes?
There are essentially three types of diabetes:
1. Type 1 Diabetes (T1D) was commonly known as “Juvenile onset diabetes” or Insulin Dependent Diabetes Mellitus (IDDM) because it is commonly diagnosed in children and young people. Individuals with T1D do not produce insulin because the cells of the pancreas because these insulin-producing cells have been damaged by an autoimmune process. The beta cells are found in areas of the pancreas known as the Islets of Langerhans, and when these cells have been damaged or destroyed, T1D results. People with T1D must use insulin injections to control their disease.
2. Type 2 Diabetes (T2D) was commonly known as adult onset diabetes or Non-Insulin Dependent Diabetes Mellitus (NIDDM). In this form of diabetes, the insulin either doesn’t produce enough insulin or the insulin that is produced does not work effectively. The insulin itself may be fine, but the cells that it is supposed to signal to take up the insulin don’t respond correctly—so it is not really a problem centered around the insulin, it is a problem centered around the cells and tissues of the body. This is where the phrase “insulin resistant” becomes important—the cells and tissues of the body do not respond to whatever insulin is produced. When the cells and tissues of the body develop insulin resistance, this is regarded as the first step in diabetes, or is considered to be “prediabetes”.
3. Gestational diabetes is a condition during pregnancy with high blood glucose (sugar) levels that often resolves after delivery. Gestational diabetes does put a woman at higher risk for T2D.
How is Diabetes Diagnosed?
There are a number of tests available to diagnose diabetes, and they all are centered around how well your body handles blood sugar. These tests include:1
- Fasting Plasma Glucose test (FPG). The FPG measures blood sugar levels. To take this blood test, you have to be fasting—in other words, don’t have any food for 10-12 hours before the test.
- In people who handle blood sugar well, the normal level of blood sugar is between 70-100 mg/dL. Generally, those with prediabetes or diabetes have blood sugar levels of 126mg/dL or higher
- Random blood sugar testing can be used to diagnose individuals with diabetes if on 2 or more occasions the blood sugar levels are higher than 200mg/dL.
- An Oral Glucose Tolerance Test (OGTT) is a test where you drink a highly sugared drink and your blood is taken at various points, but usually at one hour and at two hours.
- In people who handle blood sugar well, the normal level of blood sugar at 1 hour is less than 200 mg/dL.
- In people who handle blood sugar well, the normal level of blood sugar at 2 hours is less than 140mg/dL.
- An A1c test measures the amount of hemoglobin in your blood that has sugar molecules attached to it (Glycosylated hemoglobin).
- Hemoglobin is the protein in the red blood cells that carries oxygen to your cells and carbon dioxide away from your cells. As red blood cells age (they last about 3 months on average), the hemoglobin pulls sugar molecules out of the blood. These sugar molecules—glucose—bind to the hemoglobin. The A1c levels therefore give a “snapshot” of how much sugar has been in the blood over the last 3 months—the more sugar in the blood, the higher the A1c levels.
- Normally, A1c should be less than5.7%. Prediabetes is defined as an A1c between 5.7 and 6.4%. T2D is defined as an A1c of over 6.5%.
- A1c is used to diagnose and to help manage diabetes
What are the Symptoms of Diabetes?
Early diabetes (prediabetes) may have no symptoms—this is why yearly check-ups are recommended. Other symptoms that occur in diabetes include:
- Increased thirst
- Increased frequency of urination (even more than you might expect with the increased thirst)
- Weight loss that may occur even in the face of increased hunger
- Blurry vision (usually a late symptom)
- Slow or poor healing of relatively minor cuts, sores and scrapes
- Increased frequency of vaginal infections (usually yeast infections)
How is Diabetes Managed
Diabetes can be very well managed—and even sometimes reversed, especially when diagnosed early—by relatively simple lifestyle modifications (diet and nutrition, increased exercise, reduced alcohol intake and smoking cessation). Diabetes can also be controlled using medications called hypoglycemic—drugs that lower the blood sugar levels.
Long-term Complications of Diabetes
There are a number of possible complications of diabetes that are all, in some way, related to high levels (especially the “spikes”) of blood sugar. These high levels and spikes damage blood vessels, nerves and organs. Complications include:
- Eye diseases such as retinopathy, blind spots, blurry vision, glaucoma and cataracts
- Nerve disorders such as peripheral neuropathy, with numbness, tingling and pain in the legs and feet
- Immune disorders such as a suppressed immune system and increased frequency of infections
- Kidney disease (nephropathy) that can damage kidney function and raise blood pressure. Swelling in the feet and ankles is often related to nephropathy
- Dental diseases such as periodontitis
- Heart disease and stroke. This include high blood pressure
A Diagnosis of Diabetes—what does it mean?
Getting a diagnosis of diabetes can be traumatic and upsetting. It might help to remember, however, that there is A LOT you can do to manage diabetes—diet and exercise can make an absolutely huge difference in your life. These changes are “relatively” simple—meaning that on paper, they are easy enough to do. In real life, these changes take your commitment to them and the support of those around you. Changing your diet to a non-processed, whole foods diet that is high in vegetables, fish, nuts, seeds, beans, legumes and high quality protein (eg. from skinless chicken, turkey) may not be simple at first, but it can affect how your diabetes progresses (or IF it progresses) as well as affecting your overall health in positive ways. The same is true for increasing your level of physical activity—you don’t have to train for, or run in a marathon to increase the amount of time you spend in increased physical activities such as walking. Yet, increasing your physical activity just a bit –by just over an hour every week—can also make a huge difference for your diabetes and your overall health. You get to choose and you get to decide!
- Jacobs, Simone, et al. “A priori-defined diet quality indexes and risk of type 2 diabetes: the Multiethnic Cohort.” Diabetologia 58.1 (2015): 98-112.