Diabetes mellitus is a disease characterized by high levels of sugar in the blood. People with diabetes have problems converting the food they eat into usable energy. There are two types of diabetes mellitus: type 1 (type I) and type 2 (type II).
What is type 2 diabetes?
Type 2 diabetes, formerly called noninsulin-dependent diabetes, is a condition in which the body does not make enough, or cannot properly use, the pancreatic hormone insulin. Insulin tells the body's cells to absorb the sugar known as glucose from the blood and to use it as fuel. If the body makes only low levels of insulin or if cells become resistant to its effects, glucose will remain in the bloodstream causing chronically high blood sugar levels and preventing cells from taking up the sugar they need for metabolism. Type 2 diabetes accounts for between 90 and 95 percent of all diabetes cases in the United States.
Type I diabetes, formerly called insulin-dependent diabetes, is a much less common disorder in which the pancreas makes no insulin at all. As in type 2 diabetes, this results in high blood sugar levels and difficulty obtaining energy from food.
The American Diabetes Association (ADA) estimates that 20.8 million Americans, or about 7% of the population, have diabetes and about 95% of these cases are type 2. 14.6 million of these people have actually been diagnosed with the disease, but an estimated 6.2 million people have type 2 diabetes and do not know it. The ADA also estimates that 54 million people have prediabetes, a condition in which their blood sugar is elevated but not high enough to be considered diabetes.
Type 2 diabetes is essentially a problem making or responding to the hormone insulin. This leads to two major changes in the body: elevated levels of blood sugar and difficulty providing adequate nutrition to body cells. The symptoms that occur are secondary to these changes. If any of the following symptoms occur, you may want to consult a doctor to be tested for type 2 diabetes:
-- Extreme hunger
-- Weight loss
-- Increased thirst and frequent urination
-- Blurred vision
-- Slow-healing sores or frequent infections
-- Erectile dysfunction
Type 2 diabetes does not always cause obvious symptoms so someone can have it for years without knowing. Unfortunately, many people do not find out they have diabetes until debilitating complications develop.
What are the short term-complications of type 2 diabetes?
People with type 2 diabetes are prone to developing acute complications, which come on fast and may have grave health consequences if they are not treated quickly. Some of the most common of these are described below.
Diabetic ketoacidosis occurs when lack of insulin causes cells to starve for want of sugars. In this case, the liver will break down fats into small molecules called ketone bodies and release them into the bloodstream in an attempt to feed the tissues. Ketone bodies are acids so too many of them makes the blood pH decline. The symptoms include loss of appetite, nausea, vomiting, fever, stomach pain and a sweet, fruity smell on your breath caused by the ketones. This is a potentially dangerous condition and can lead to a medical emergency: if untreated, it can progress to unconsciousness and coma, even death. Contact a doctor immediately if any of these symptoms occur.
Hyperglycemia or high blood sugar can occur when you eat too much sugar or when not enough insulin is either released or received to clear the sugar from the blood. To avoid this, diabetics should check their blood sugar level often and watch for symptoms of hyperglycemia that include: frequent urination, increased thirst, dry mouth, blurred vision, fatigue, and nausea. If untreated, hyperglycemia can lead to more serious complications. If you experience the above symptoms, or if your blood sugar level is always above 250 mg/dL, consult your doctor right away or seek emergency care.
If your blood sugar level drops too low, it is called hypoglycemia. This can be caused by skipping a meal, by increased physical activity, or simply as a side effect of your medication. You can prevent this by regularly checking blood sugar levels and watching out for the symptoms, which include sweating, shakiness, weakness, hunger, dizziness, and nausea. If left untreated, later signs of hypoglycemia include slurred speech, drowsiness, and confusion and eventually, unconsciousness. To treat hypoglycemia, eat or drink something that will quickly raise your blood sugar level (like fruit juice). You may want to contact your doctor to discuss how you best to avoid hypoglycemia in the future.
What are the long-term complications of type 2 diabetes?
Living with type 2 diabetes can cause serious chronic complications that can significantly shorten the lives of diabetics. These complications develop over long periods of time and are mostly due to chronically elevated levels of sugar in the blood. Controlling blood sugar levels reduces the risks of developing all of these complications so if you are a diabetic, monitoring your blood sugar and keeping the level as close to normal as possible is critical.
Heart disease and stroke
People with type 2 diabetes tend to have high blood pressure and elevated blood cholesterol, both of which increase their risk of developing vascular diseases such as coronary artery disease. Chronically elevated blood sugar also tends to cause poor circulation, leading to increased risk of heart attack and stroke.
The kidney's job is to clean the blood and they perform this job several times each day. When the blood contains high levels of sugar, it makes the kidney's job much harder. High blood sugar raises the blood pressure in the kidneys and can lead to reduced kidney function and even chronic renal failure. In fact, diabetes is by far the leading cause of kidney failure in America.
One of the most common complications of diabetes is diabetic neuropathy. Neuropathy is damage to the nerves and it can occur throughout the body, often caused by poor circulation. The nerve damage can cause tingling or numbness, often in the extremities, or conversely, chronic pain.
Poor circulation and nerve damage in the feet can lead to serious complications for diabetics. When the protective pain sensations are lost, diabetics can injury their feet without realizing it. Reduced circulation impairs the foot's ability to heal and the result can be chronic infections requiring amputation.
People with diabetes are more prone to skin infections than the general population. Reduced circulation in the skin makes infection more likely and also impairs wound healing; this makes any skin injury much more serious. Luckily, most skin problems can be treated easily if they are caught early.
The retina is the portion of the eye that receives and processes visual images. Having high blood glucose and high blood pressure for a long time can damage the tiny blood vessels that supply the retina. Reduced retinal blood flow can cause blurred vision and over time, blood can begin to leak out of the weakened blood vessels, preventing light from reaching the retina. This causes visual impairments and can also permanently damage the retina itself, leading to blindness.
Stomach problems: gastroparesis
Damage to the vagus nerve caused by high blood sugar can lead to gastroparesis, a condition in which the stomach holds onto its contents for too long. Normally, the vagus nerve signals the stomach to contract and expel its contents into the small intestine. When food stays in the stomach too long, it leads to uncomfortable symptoms like acid reflux, nausea, and vomiting.
Type 2 diabetes is most often caused by cells becoming less sensitive to the hormone insulin. This phenomenon is called insulin resistance. Insulin normally signals cells to grab up and use sugar (glucose) from the bloodstream, so if cells are not getting the message, glucose stays in the blood. But what makes cells ignore this critical message? While the exact causes remain unknown, it appears that having high levels of insulin in the blood for a prolonged period can alter the receiving mechanisms that many cells have for insulin (called insulin receptors) making them less able to respond to the message.
So what makes insulin levels high in the first place? Unfortunately, scientists do not know exactly why this happens, but one thing is clear: obesity is a major factor. Several other risk factors are known including other preventable risk factors, like high blood pressure and some that are not preventable, like family history.
Type 2 diabetes can also occur when the pancreas produces only low levels of insulin. In this case, there is not enough insulin to signal body cells to take up sugar and the result is the same as insulin resistance: high blood sugar and starving cells.
While doctors do not know exactly what causes type 2 diabetes, they do have a very good understanding of the risk factors for developing the disease. Many of the risk factors are preventable and several studies show that limiting them can reduce your chances of developing the disease. What follows are the non-controllable and controllable risk factors for developing type 2 diabetes.
Non-controllable risk factors for type 2 diabetes:
People who have a close relative with type 2 diabetes are much more likely to develop the disease themselves. However, it does not mean that you are guaranteed to have type 2 diabetes if your mother did. Genetic studies suggest that you can inherit a tendency to develop type 2 diabetes, but that you can still avoid the disease in many cases by limiting the preventable risk factors such as obesity.
For unknown reasons, several ethnic groups have a higher than average risk of developing type 2 diabetes. These include Alaska Natives, Asian Americans and Pacific Islanders, Hispanic/Latinos, Native Americans, and African Americans.
The risk of developing type 2 diabetes increases as we age and becomes significantly higher after age 45. This could be due to changes in hormonal patterns that occur with age or to changes in the distribution of muscle and fat that also tend to accompany aging. However, don't think that only those older than 45 can get type 2 diabetes. On the contrary, diabetes rates have recently been on the rise in young adults and even in adolescents and children.
Gestational diabetes is a temporary condition that develops in pregnant women and which usually resolves after delivery. However, someone who develops gestational diabetes during pregnancy is more likely to develop type 2 diabetes later on in life.
Controllable risk factors for type 2 diabetes:
A major preventable risk factor for developing type 2 diabetes is carrying excess weight. The risk is highest if you carry the weight mostly around the middle of your body (an "apple" shaped body). Excess fat appears to contribute directly to insulin resistance, though it is unclear exactly how this happens.
Carrying extra weight also heightens your risk of developing several other diseases including heart disease and stroke. The body mass index or BMI is a general measure of how much excess weight one carries. Your BMI takes into account your height and weight; higher numbers mean you carry more fat. If your BMI is above 25 but below 30, you are considered overweight. If your BMI is between 30 and 39 you are considered obese, while a BMI 40 or above is considered extremely or "morbidly" obese.
The less active you are, the greater your risk of developing type 2 diabetes. Exercising fewer than three times a week can be considered a potential risk factor for developing diabetes. Not only does physical activity help control weight, it allows your body to use up blood sugar, makes your cells more sensitive to insulin, and boosts your level of "good" cholesterol.
Prediabetes is a condition in which your blood sugar level is higher than normal, but not high enough to be called type 2 diabetes. Without lifestyle changes, prediabetes often progresses to type 2 diabetes.
Other risk factors for developing type 2 diabetes include:
-- Poor diet
-- Previous diagnosis with impaired glucose tolerance or high fasting glucose levels
-- High blood pressure (140/90 mm Hg or higher)
-- HDL cholesterol of less than 35 mg/dL or triglyceride level of greater than 250 mg/dL
-- Polycystic ovary syndrome, also called PCOS (women only)
-- Other clinical conditions associated with insulin resistance
By definition, diabetes is an elevated blood glucose level that persists over time. Since type 2 diabetes may occur with no symptoms, it is possible to have the condition for years without noticing. Over time, symptoms will develop and they may become severe. You may want to have your blood sugar tested as part of your yearly physical examination by a physician, especially if you have one or more risk factors for developing diabetes. The American Diabetes Association recommends being tested yearly beginning at age 45, especially if you are overweight.
Diagnosing type 2 diabetes:
Fasting blood glucose test
After fasting overnight (at least 8 hours) a blood test can be performed to check your blood sugar. If your blood glucose level is 126 milligrams per deciliter (mg/dL) after fasting for 8 hours on two separate testing occasions, you have diabetes. If your blood glucose is between 100 and 125mg/dL, this is considered prediabetes, which is a risk factor for developing diabetes.
Random (non-fasting) blood glucose test
If you have a blood sample taken - regardless of how long it has been since you last ate - and your non-fasting blood glucose is higher than 200 mg/dL, the doctor will suspect diabetes. This is especially true if you are having other diabetes symptoms such as increased thirst and urination. A fasting blood glucose test must be done to confirm the results.
Oral glucose tolerance test
The oral glucose tolerance test examines how well your body metabolizes sugar after it is introduced into your body. After fasting overnight, the doctor will provide you with a sample of sugary liquid to drink. Then, a blood sample is taken every 30 to 60 minutes after you drink the solution for 2 to 3 hours. Diabetes is diagnosed if your blood glucose level is higher than 200 mg/dL after 2 hours. If your blood glucose is between 140 and 200 mg/dL it is considered "impaired glucose tolerance" or prediabetes.
Glycated hemoglobin (A1C) test
If you're diagnosed with diabetes, your doctor may also suggest a glycated hemoglobin (A1C) test. This test gives a measure of the average blood sugar level over the previous 1 to 3 months. The A1C test looks at the oxygen-carrying molecules called hemoglobin that are found in red blood cells and determines how much sugar they have been exposed to. The doctor takes a blood sample and examines what proportion of your hemoglobin molecules have sugars attached to them (how many are "glycated"). The higher the proportion of glycated hemoglobin in the blood, the more sugar there has been in the blood over the past few months. A target A1C result is 7 percent or less.
All the treatments for type 2 diabetes focus on keeping blood sugar levels within normal limits. The most important and most effective treatment is lifestyle change including eating right, losing weight, and increasing exercise/activity levels. Many people with type 2 diabetes can control their disease just by improving their diet and increasing their activity level. However, if this alone does not work, doctors can prescribe medications that can help stabilize blood sugar levels. The ultimate goal of treatment is to reduce the effects of diabetes symptoms and prevent secondary complications from arising.
Eating right is one of the most important ways to help keep blood sugar levels in line, even if you are not overweight. This includes choosing healthy foods, eating sensible portions, and eating at appropriate intervals. A nutritionist can help you plan meals with the right combinations of nutrients and appropriate energy content. Eating foods with a low glycemic index helps reduce the rate of rise in blood sugar that occurs after a meal.
The glycemic index ranks sugar-containing foods based on how much and how quickly they increase blood sugar levels. Foods with a high glycemic index such as white bread and most breakfast cereals tend to cause rapid spikes in blood glucose and therefore should be consumed only in limited amounts. Foods with a low glycemic index such as most vegetables and whole grains tend to cause a slower and less pronounced increase in blood sugar and thus should be the preferred source of carbohydrates.
In general, a healthy diet includes lots of nutrient rich foods like fruits, vegetables, and whole grains, as well as fish. But a healthy diet also avoids foods that are low in overall nutrients and limits the intake of trans and saturated fats, cholesterol, sodium, and foods with a high glycemic index. Controlling portion size and eating frequent, small meals also helps the body better digest food and limits the rise in blood sugar levels.
Reducing your weight and BMI to appropriate levels also helps keep blood sugar levels down and since obesity is intimately tied to insulin resistance, losing weight can help your body respond better to insulin.
A simple way to lose weight is to figure out the number of calories you need to consume each day to maintain your weight and then eat fewer calories than you need. That way, your body can obtain the extra energy it needs by burning fat and you will lose weight. This is much easier to do when you eat healthy, nutrient-rich foods that fill you up and eliminate empty calories like soda pop.
Besides reducing your caloric intake, the other factor involved in weight loss is activity. Increase the amount and intensity of your physical activity to exceed the number of calories you take in and you are certain to lose weight.
When you have reached an ideal weight as determined by a doctor or nutritionist, you may be able increase your caloric intake a little but the important thing is to always expend all the calories you take in; otherwise, they will be stored as fat and you will gain weight.
Attaining a healthy weight can help reduce insulin resistance and keep blood sugar levels in line. But losing weight alone is not the full story. Doctors recommend shedding the pounds that accumulate around the midsection, the ones that contribute to an "apple shape" figure. Increasing your activity level can help redistribute your existing weight to a healthier pattern. Even modest weight loss can improve blood sugar levels by changing fat into muscle mass. Exercise can also improve circulation and lower blood pressure, blood cholesterol levels, and triglycerides, all of which reduce the risk of diabetes complications such as heart disease, stroke, and vision loss.
How much activity do you need? According to the American Heart Association, the average person should aim to get at least 30 minutes of moderate exercise five times per week or 20 minutes of vigorous exercise three times per week. If you are trying to lose weight, you should aim for 30 to 60 minutes on most days.
IMPORTANT: before starting any new exercise regimen, consult a health professional to determine what activities are best for you. A doctor can also help you determine how often to exercise and how to maintain healthy nutrition and normal blood sugar levels when you exercise.
Blood sugar monitoring:
Frequent measurement of your blood glucose levels can help you determine the effects that your lifestyle changes and medications are having on your blood sugar. Several types of glucometers are available but they all work by taking a very small sample of blood and analyzing the glucose content. Results are obtained in less than one minute and can help you determine what foods to avoid (those that cause large or rapid spikes in your blood glucose level) and determine when to eat in relation to exercise. You can also monitor the effects of your medications on your blood sugar and make sure to avoid hypoglycemia (low blood sugar) that can be a side effect of some medications.
While everyone with type 2 diabetes can benefit from changes in diet and exercise, in many cases these alone are not enough to keep blood sugar within normal limits. In those cases, a doctor may prescribe one or more medications. Medications for type 2 diabetes work by helping the body respond better to insulin or by helping keep blood sugar levels down. Several classes of medications are commonly used, either alone or in combination.
Sulfonylureas stimulate the beta cells of the pancreas to release more insulin. These drugs are generally taken once or twice a day before meals. Several sulfonylurea drugs are on the market but some examples include glyburide (Micronase, Glynase, and Diabeta), and glimepiride (Amaryl). These drugs can cause hypoglycemia (low blood glucose levels) as a side effect of insulin release.
Meglitinides stimulate the beta cells of the pancreas to make more insulin right after meals to decrease the glucose in the blood. They are usually taken before each meal. Examples of drugs in this class include repaglinide (Prandin) and nateglinide (Starlix). The side effects of meglitinides include weight gain and hypoglycemia (though this is less of a problem than with sulfonylureas).
Biguanides decrease the amount of glucose that is made by the liver, lowering overall blood glucose levels. Metformin (Glucophage), a common biguanide, also makes muscle cells more responsive to insulin. This allows muscle cells to take up and use (or store) glucose from the bloodstream and lowers blood insulin levels. Biguanides are usually taken twice a day. The side effects of biguanides include nausea, diarrhea, and cramping. Also, people with kidney problems (a common complication of type 2 diabetes) cannot take this medication so your doctor may perform additional tests to evaluate the functioning of your kidneys before prescribing this medication.
Alpha-glucosidase inhibitors block the breakdown of sugars and starches in the digestive tract, thus reducing the impact of ingested carbohydrates on blood sugar levels. These drugs do not impact the liver or the glucose that is already in the blood, only the glucose that can potentially enter the body through the digestive tract. Examples of drugs in this class include acarbose (Precose) and meglitol (Glyset). They are normally taken along with the first bite of each meal. Side effects of alpha-glucosidase inhibitors include gas and diarrhea.
Thiazolidinediones reduce glucose production in the liver; they also partially reverse insulin resistance by improving the sensitivity of insulin receptors in muscle, liver, and fat cells. This helps the body use insulin better and so these medications are often called "insulin sensitizers". The two members of this class currently on the market in the U.S. are pioglitazone (ACTOS) and rosiglitazone (Avandia). Both of these drugs may slightly increase the risk for heart failure in some individuals and one recent study showed that rosiglitazone may cause a small increase in the risk of heart attacks. For the first year of thiazolidinedione therapy, your liver enzyme levels are monitored as a precaution because a similar drug that is no longer on the market increased the risk of liver damage. Otherwise, both drugs generally have few side effects.
Some people who have type 2 diabetes may need to take insulin in addition to other treatments. Insulin is a protein hormone so when taken orally, it gets digested in the stomach just as the protein in a steak does. This is why insulin must be taken by injection. There are several varieties of insulin that differ in their longevity in the body, including: insulin lispro (Humalog), insulin aspart (NovoLog) and insulin glargine (Lantus).
While the most important and effective treatment for type 2 diabetes involves a serious and long-lasting commitment to changes in diet and exercise, this is not always enough. When lifestyle changes alone fail, often taking a combination of the drugs mentioned above, in addition to dietary changes and increased activity levels, are an effective way to control type 2 diabetes. This is most effective when it involves combining drugs from the different classes, for example, taking an alpha-glucosidase inhibitor to reduce absorption of sugars from the digestive tract and a thiazolidinedione to reduce insulin resistance and production of glucose in the liver.
Taking care of your feet:
People with diabetes are prone to foot problems. Poor circulation and nerve damage in the feet can lead to serious complications because without the protective pain sensations, you can injure your feet without realizing it. Reduced circulation also impairs the foot's ability to heal and the result can be chronic infection, eventually requiring amputation. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) recommends the following to take care of your feet:
-- Wash your feet in warm water every day
-- Look at your feet every day to check for cuts, sores, blisters, redness, calluses, or other problems
-- If your skin is dry, rub lotion on your feet after you wash and dry them
-- File corns and calluses gently with an emery board or pumice stone
-- Cut your toenails once a week or when needed
-- Always wear slippers or shoes to protect your feet from injuries
-- Always wear socks or stockings to avoid blisters
-- Wear shoes that fit well
-- Before putting your shoes on, feel the insides to make sure they have no sharp edges or objects that might injure your feet
-- Tell your doctor right away about any foot problems
If you have type 2 diabetes, you should visit a health care provider regularly and have a physical examination that includes:
-- Glycated hemoglobin (A1C)
-- Blood pressure check
-- Foot and skin examination
-- Ophthalmoscope (eye) examination
-- Neurological examination
-- Random microalbumin (urine test for protein)
-- BUN and serum creatinine blood tests
-- Serum cholesterol, HDL, and triglycerides
-- Dilated retinal exam
While there are several risk factors for type 2 diabetes that you cannot control, the good news is that you can reduce your risk substantially by maintaining a healthy body weight and keeping an active lifestyle. Even if a close relative has diabetes, or if you are a member of a high risk ethnic group, you can often prevent or at least forestall the onset of type 2 diabetes by living a healthy lifestyle and seeing your doctor regularly for diabetes screening.
Get screened regularly:
Everyone over 45 should have their blood glucose levels checked at least every 3 years. If you have any risk factors for diabetes, you should have your blood sugar checked more often, starting at a younger age. If you test as having prediabetes, a condition in which your fasting blood sugar level is between 100 - 125mg/dL (higher than normal but not high enough to be called type 2 diabetes) you should be tested every year and institute lifestyle changes to prevent the onset of diabetes.
Maintain a healthy weight:
A major preventable risk factor for developing type 2 diabetes is carrying excess weight. The risk is highest if you carry the weight mostly around the middle of your body (having an "apple" shape). Excess fat appears to contribute directly to insulin resistance, though it is unclear exactly how this happens.
Carrying extra weight heightens your risk of developing several other diseases including heart disease and stroke. The body mass index or BMI is a general measure of how much excess weight one carries. Your BMI takes into account your height and weight; higher numbers mean you carry more fat. If your BMI is above 25 but below 30, you are considered overweight. If your BMI is between 30 and 39 you are considered obese, while a BMI 40 or above is considered extremely or morbidly obese.
The less active you are, the greater your risk of developing type 2 diabetes. Exercising fewer than three times a week is considered a risk factor. Not only does physical activity help control weight, it also allows your body to use up blood sugar, makes your cells more sensitive to insulin, boosts your level of "good" cholesterol, and lowers blood pressure.
Commit to changing your lifestyle:
Change can be difficult, but if you are in a high risk category, changes in the way you live may be necessary to avoid diabetes. You can make it easier by making a specific plan for yourself with enumerated benchmarks for change. These goals can start out small, but over time you can have them build into large changes. Try to anticipate ahead of time the things that might cause you problems in reaching your goals and have a contingency plan in place. Seek support from family members, friends, or others that share your situation whenever necessary. Consult a doctor, nurse, counselor, or nutritionist for advice on how to stay on track. Finally, choose constructive ways to reward yourself for reaching goals, saving the largest rewards for the goals that are the toughest to attain.