Questions About Diabetes (Part 1)


Dr.Hister answers to 24 common questions


1. What is diabetes?


The common definition of diabetes is: a disorder of glucose (sugar) metabolism in which the blood sugar level is above a level that is considered normal.

Unfortunately, though, that definition really only describes part of the diabetes problem because it fails to tell you what happens when your blood sugar level goes up and stays high, and that’s really the major concern about blood glucose levels, not a temporary and occasional spike in blood sugar, but rather a prolonged and persistent rise in that level, because higher persistent blood sugar levels damage the arteries (the blood vessels that carry oxygen to the tissues). And it’s the damage to the arteries (along with other factors) that in turn results in the serious complications that are linked to diabetes. So it’s best to think of diabetes as a disorder in which raised blood sugar levels eventually injure the arteries all over the body.


2. What is glucose and why do we need it?


Glucose is life’s fuel. The cells in your body break down glucose circulating in the blood system (glucose levels go up following a meal, and gradually go down afterwards) and they turn that glucose into the energy that is used for everything the body must do: moving, breathing, repairing tissue injuries, growing, multiplying, and so on. Thus, a steady supply of glucose is necessary for survival, but too much glucose is clearly very harmful.


3. What is insulin and how does it affect glucose levels?


 Insulin is a hormone secreted by the beta cells of the pancreas and its job is to keep a lid on glucose levels. Some insulin is also produced in the liver and this may eventually be a source of new diabetic therapies.So if you don’t produce enough insulin from your pancreas or if your cells somehow stop responding to the insulin that is produced, your blood sugar levels start to go up and stay up for much longer.


4. What is insulin resistance?


Over the last 2 decades, we’ve learned that in people who go on to develop the most common form of diabetes known as Type 2 diabetes (see below), the cells of the body become steadily more resistant to the insulin that the body is producing, that is, these people still make lots of insulin but their cells don’t respond to that insulin the way they once did, so their blood glucose levels are higher than in people who respond normally to insulin. People with early insulin resistance don’t yet have high enough blood sugar levels to be diagnosed with diabetes. However, if they don’t alter the lifestyle factors that brought on the insulin resistance most of these people will be diagnosed as having diabetes unless they make changes to reverse their situation.


5. What is the metabolic syndrome?


When insulin resistance is combined with several other health problems, the condition is known as pre-diabetes or metabolic syndrome. There is some debate about this but overall, most experts agree that you have the metabolic syndrome if you have 3 or more of the following:

- A low HDL level (that’s the so-called “good cholesterol”)

- High blood pressure

- A high triglyceride level (that’s another of the fats that circulate in the blood, and is a measure of how well we metabolize carbohydrates)

- High blood sugar (but not high enough yet to be diabetes), and Abdominal obesity, or weight around the middle (for reasons that are still not fully clear, weight carried around the middle – the so-called “apple” shape – is much worse for your metabolic health than weight carried elsewhere like the hips and thighs – the so-called “pear” shape).


6. Why is it very important to know if you have pre-diabetes?


There are at least two major reasons that you need to know if you have pre-diabetes. First, even though your blood sugar levels are not yet high enough to be labeled as diabetes, those somewhat elevated glucose levels are still steadily damaging your arteries. Second, happily, we now know very clearly that you can totally prevent or at the very least significantly delay the onset of diabetes if you make the lifestyle changes that lower your risk of ending up with diabetes. For example, a recent excellent study showed clearly that if a person with pre-diabetes switches to a Mediterranean-style diet and adds a small handful of nuts every day to that healthy diet, they can quickly reverse their pre-diabetes condition, even if they don’t lose any overall weight.


7. So what is this magical Mediterranean diet?


No surprise: it’s the diet eaten by people who cluster around the Mediterranean Sea. But as anyone who’s ever visited Greece or Italy or France or Lebanon or Israel will quickly point out, the people in each of those Mediterranean-bordering countries eats quite a different diet, which is true, of course, although all the traditional diets in those countries do have a few elements in common:

- A healthy focus on lots of fruits and veggies (I would also add my own bias that these people get an added benefit from generally eating fresh fruits and veggies, because one thing that strikes any visitor to Mediterranean lands is how often the people there shop for fresh produce, in part because fresh produce seems to be so readily available, and in part because their fridges are so much smaller than ours so they simply can`t store 2 dozen apples for 2 weeks)

- Lots of whole-grain cereals and breads (you can’t think of a Mediterranean meal without some kind of fresh bread or other baked product like pita)

- Olive oil for cooking (but olive oil is also often added at the table to hummus and bread and pasta and other dishes)

- A moderate intake of fish (which also means a significantly lower intake of meat than is common in North America)

- A low intake of dairy products (in traditional Mediterranean diets, this has always consisted of full-fat dairy products while in North America we have tended to push low-fat dairy products)

- Moderate intake of alcohol (although the definition of “moderate” in some of those countries is way different from how I would define it), and

- A healthy intake of nuts and legumes (particularly, I think, beans).


8. How is diabetes diagnosed?


The typical way diabetes is diagnosed is through a blood test done after an overnight fast. If the fasting blood sugar level is 7.0 mmol/L or higher, you have diabetes. But many people are diagnosed with diabetes after a random blood test, that is, one that was done without fasting, and although your blood sugar reading may be higher at that point because you just ate something, for example, it should still not be over 11.1 mmol/L. The third way to be diagnosed is an oral glucose tolerance test in which you drink a standard amount of glucose dissolved in water. Blood is drawn 2 hours afterwards, and if it’s over 11.1, you will be diagnosed with diabetes. In the case of pregnant women, blood is drawn following a 1 or 3 hour oral glucose tolerance test. It is important to note that the blood sugar values for pregnant woman are lower than the rest of us.


9. What are the symptoms of diabetes?


The most common early symptoms of diabetes include:

- Excess thirst

- Urinating very often

- Excess hunger

- Fatigue

- Weight loss (although many with Type 2 Diabetes experience weight gain)


As the disease progresses, other common symptoms include:

- Vision abnormalities

- Slowly-healing sores

- Skin ulcers on the legs

- Numbness or tingling in the fingers, legs and/or toes

- Gum disease

- Erectile dysfunction


While the symptoms of Type 1 diabetes usually come on swiftly and dramatically, making the diagnosis usually a fairly easy task, the symptoms of Type 2 diabetes can be very mild and subtle, which is why it’s commonly said that half the people with diabetes don’t know they have it. In fact, the average Type 2 diabetic is said to walk around for 6 years with abnormal blood sugar levels before being diagnosed with diabetes, and the sad thing about that is that the damage to the arteries that occurs in diabetes is going on for all those 6 years, although the person doesn’t know it.


10. How many types of diabetes are there?


Currently, there are two particularly well-known types of diabetes, cunningly named Type 1 and Type 2 diabetes, although the diabetes of pregnancy is now considered a separate specific type, too, and has been given its own name, gestational diabetes.

There are other, less common types of diabetes such as MODY (Maturity Onset Diabetes of the Young) and LADA (Latent Autoimmune Diabetes of Adults). In fact, as time goes on, and as we discover more secrets about diabetes and raised blood sugar levels, I’m fairly certain we will eventually end up with several other distinct types of diabetes, such as for example, dementia linked to insulin and blood sugar abnormalities.


11. What is Type 1 diabetes?


Type 1 diabetes used to be known as juvenile onset diabetes because it nearly always came on in very young people, and rarely in those over the age of 30. Type 1 diabetes, which accounts for roughly 10 % of all diabetes cases, happens because the Type 1 diabetes is what is known as an auto-immune disease; a condition in which the body destroys its own cells, which in the case of Type 1 diabetes means the body destroys its own insulin-producing cells in the pancreas. Other common examples of auto-immune disorders include lupus, rheumatoid arthritis, thyroid gland inflammation, Crohn’s disease, Multiple Sclerosis, and celiac disease. Since the insulin-producing capacity of the body disappears in Type 1 diabetes, it must be treated with life-long insulin replacement therapy, most often by regular injections through syringes, pens, and increasingly, pumps.


12. Why does the body destroy its own cells?


We still don’t know why the body begins to self-destruct but the common theory is that something such as a virus or a toxin in the environment turns the body against itself, and this is more likely to happen, of course, in someone who is already genetically pre-disposed to that condition, which is why, for example, the relatives of people who have celiac disease are much more likely to also be diagnosed with celiac disease than someone who comes from a family where there is no history of celiac disease.

Another increasingly favoured theory about the origin of these disorders is called the hygiene hypothesis, which argues that lots of conditions may be increasing – allergies, asthma, some auto-immune disorders – because these days kids are brought up in environments that are actually too clean, that is, kids these days are not exposed to the viruses, the bugs, the dirt, the toxins that people of my age were so much more likely to encounter all around us when we were kids, and thus, modern kids’ immune systems over-react when they finally encounter such environmental toxins a bit later in life. Clearly, though, these kinds of problems only happen to some people, and not to others, so most experts feel that there must also be a genetic component to such conditions.