Diabetes symptoms were known even to old Egyptians and the first written record of this illness was found in a papyrus that dates back to 1500 BC. The term diabetes was coined by Aretaeus of Cappadocia in the 2nd century BC. He observed that patients suffering from diabetes have also increased urine production and term diabetes is derived from the Greek term for siphon and it puts emphasis on the main diabetes symptom i.e. strong and continuous flow of water. Since 6th century, Indian doctors knew that urine of diabetics has sweet taste. This discovery remained hidden to European medical science until the 17th century when Thomas Willis introduced tasting of patients’ urine as a method of diagnosing diabetes.
In 1889 German doctors Joseph von Mering and Oscar Minkowski published their discovery relating to diabetes. During experiments performed on dogs they found out that after the removal of pancreas diabetes symptoms appear. A British scientists Edward Sharpey-Schafer further developed their findings and he proved that a substance affecting the metabolism of sugar is formed in the pancreas. Later he located the formation in islets of Langerhans and named the substance insulin. Frederick Banting and Charles Best had a breakthrough in treatment of diabetes when they isolated insulin and then verified its effectivity.
The initial excitement from insulin as a universal treatment of diabetes wore off quickly. Insulin wasn’t lethal to diabetics but after several years of using insulin secondary complications started manifest itself. The most affected were eyes, kidneys, nerves and lower limbs. Since 1947 prevailed the opinion that insulin should be administered at the right time and that the insulin dose should be appropriate to the blood glucose level and its development in next hours should be taken into consideration as well. This approach to insulin administration decreased the number of deaths caused by later complications. Since the 70’ an approach to diabetes treatment including changes in lifestyle (exercising, changing eating habits) and education of patients became prevalent.
Diabetes is characterized by a high blood glucose level. This situation is called hyperglycemia and it can lead even to glucose excretion in urine (glycosuria). Furthermore, a larger amount of fatty acids is released and degraded to hydroxybutyric acid which causes diabetics the well known metabolic acidosis. Besides that, acetone is formed as well. Because reproduction of fat in liver is insulin independent, the larger amount of free fatty acids causes the so called fatty liver disease also known as hepatic steatosis.
The cause of diabetes can be lowered (or completely inactive) insulin production in the pancreas or its insufficient effect in tissues even if the insulin production is normal. Diabetes is divided according to their cause into two types.
Diabetes type 1 is insulin-dependent and diabetes type 2 is noinsulin-dependent. Besides these two basic types of diabetes there is also a secondary form of diabetes occurring together with tumorous or inflammatory pancreatic diseases and also diabetes related to pregnancy (gestational diabetes).
Diabetes type 1 is characterized by damage of pancreatic beta cells which ensure insulin production in the body. The result of the damage is a lower production of insulin which must be delivered to the body by injections. Destruction of beta cells is induced by an autoimmune reaction of the body and inflammation that follows. Some people have an inborn tendency to this autoimmune reaction during which the antibodies attack body tissues. This reaction is often started by a viral infection. Diabetes type 1 begins during childhood or puberty. It is characterised by a total lack of insulin. The onset of the disease is usually quick. Among the symptoms belong a quick loss of weight, vomiting, frequent micturition, great thirst and very often also severe stomachaches. People can sometimes even lose consciousness. They can also experience a loss of appetite or a ravenous hunger but they lose weight in both cases.
When the administration of insulin begins, the state is temporarily stabilized and the production of insulin can be even partially restored. However, this doesn’t last for very long and the body stops producing insulin within 5 years. The patient is then dependent on insulin injections. The dosage of insulin is stabilized during this period. The better control patients get over their eating habits, the better prognosis of their treatment is. Meals and menus have to be prepared with exchange units, simple sugars and physical activity in mind.
Diabetes type 1 is often accompanied by other autoimmune disorders, especially bowel diseases caused by celiac disease (gluten intolerance), decreased production of corticoids and thyroid diseases.
Diabetes type 2 is characterized by insulin secretion disorder and by lower effectivity of insulin in tissues. This type usually manifest itself when people reach the age of 40 years and besides a genetic predisposition it can be caused by obesity, overeating, inadequate diet and a lack of physical activity. Diabetes type 2 can be also triggered by chronic stress. The paradox is, that patients suffering from this type of diabetes can have even higher production of diabetes. The problem is that the insulin isn’t effective enough in the muscle tissue or in other words, stabilisation of increased blood sugar level requires the pancreas to release more insulin into blood to achieve the same result. The primary function of insulin isn’t lowering blood sugar level. It is creating energy reserves (i.e. fat and glycogen storage). Lowering the blood sugar level is simply a necessary result of insulin efforts to create sufficient energy storage in cells. The more insulin molecules circulates in the blood, the more is the primary function of insulin stimulated and the more storage fat is formed. That is why obesity is such a problem for people diagnosed with diabetes type 2.
Genetic predispositions are much more important in relation to diabetes type 2 and that is why the number of patients diagnosed with diabetes in the same family line grows as they get older and more obese. If one of the parents is a diabetic, the chances that their child will be diagnosed with diabetes are doubled in comparison to a child of non-diabetics. If both of the parents are diabetics, the probability is much higher. In the light of new findings, it seems very probable that the onset of diabetes can be prevented (or delayed considerably) by having appropriate weight, right diet and physical activity. We have to realize that diabetes isn’t genetically given, the predispositions to diabetes are. These predisposition can manifest itself only when other factors contribute to them. If these factors are negated, the probability that diabetes will appear is decreased dramatically. The most common accompanying disease of diabetes type 2 is metabolic syndrome which is a disease characterized by obesity (waist circumference of women above 80 cm and waist circumference of men above 94 cm), higher concentration of lipids in the blood (above 1.7 mmol/l of blood), lower concentration of HDL cholesterol (men - under 1.0 mmol/l of blood, women - under 1.3 mmol/l of blood) and usually also by higher blood pressure (130/85 mm Hg).
Secondary diabetes can be caused by a variety of other illnesses. Besides the previously mentioned inflammatory and tumorous conditions of the pancreas, effectivity of insulin molecules can be decreased by a pancreas injury, genetic defects in function of beta cells, genetic defects inducing decreased effectivity of insulin molecules, formation of antibodies against insulin receptors, various infections, disorders of endocrine glands or other illnesses.
Gestational diabetes is defined as a disorder of glucose tolerance diagnosed during pregnancy. Gestational diabetes test is taken at the beginning of pregnancy and in the 24-28th week of pregnancy. Women must take this test after an 8-hour fast and the test has to use venous blood (blood from a vein, not from a finger). Blood sugar level test must be performed in a biochemical laboratory because a portable glucose meter is not precise enough. A control OGTT is performed 3 or 6 months after the birth and in many cases is this pregnancy disorder stabilized and the blood glucose level returns to it physiological value. If this is not the case, the higher blood sugar level can lead to permanent diabetes.
Blood sugar level of healthy people can be between 3.5 and 6.6 mmol in one liter of blood during 24 hours. The physiological value ranges from 4.0 to 5.5 mmol in one liter of blood. Rise to 6.0 mmol doesn’t indicate diabetes, it can be a result of natural body processes. If the doctor has comparable blood sugar levels from previous tests at his or her disposal, it is possible to say if the state is normal or if the results indicate a disorder. In majority of cases, the previous blood sugar levels are unknown and increased blood sugar level can be classified as diabetes or at least as prediabetes. In any case, continuous medical monitoring is desirable.
Insulin and glucagon are hormones which maintain a stable blood glucose level. Their activity must be controlled very precisely and the regulation of their activity is disrupted by diabetes. It is caused either by a lack of insulin, glucagon activity or other glucose tolerance effects which are stronger than the insulin effects. The transport of glucose from blood to cells is reduced and the concentration of glucose in blood rises.
Symptoms of diabetes
Genetic predisposition i.e. probability of being diagnosed with diabetes is higher if your relatives suffer from this illness.
Medical signs include excessive thirst and urination, headaches, overall debility and weakness, loss of appetite, itching skin, genital itchiness, vision disorders, sexual dysfunctions, slow healing of wounds, muscle cramps and purulent skin diseases. Some people can have increased appetite and lose weight at the same time.
Diabetes doesn’t usually manifest itself in all of these symptoms and approximately 7% of diagnosed diabetics doesn’t have these symptoms at all. People can have some of these symptoms temporarily and then the symptoms disappear.
If the blood sugar level is higher than 7.0 mmol/l of venous blood at any time during the day and approximately 2 hours after eating is the blood sugar level higher than 11.1 mmol/l of blood, it is highly probable that diabetes mellitus is going to be diagnosed. If there are symptoms such as frequent urination, thirst or weight loss even if you aren’t dieting, the diagnosis of diabetes is almost certain. Diabetes can be diagnosed quickly by repeated testing of blood sugar level at any time during the day. If the blood sugar level is higher than 11.1 mmol/l of blood at least twice in a row, the diabetes is almost certainly confirmed. Because the diagnosis of diabetes isn’t confirmed by one test, other similar and repeated tests must follow.
Besides the laboratory tests focusing on glucose, fats, cholesterol and uric acid in the blood, liver function test there is also so called stress test (its medical name is the oral glucose tolerance test - OGTT). The patient is given 75 grams of glucose dissolved in 300 ml of water. The solution must be drunk within 3 to 5 minutes. The blood glucose level is taken in regular intervals 2 hours later after drinking the glucose solution. If the blood glucose level in one liter of blood is lower than 7 mmol before drinking the solution and below 11.1 mmol two hours after drinking the solution, the glucose tolerance is not disturbed. If the blood glucose level is higher than 7 mmol after a fast and higher than 11.1 mmol after drinking the solution, the diagnosis of diabetes is confirmed. In some countries, the bottom line used for diagnosing diabetes isn’t 7 mmol after a fast but 8 mmol. This difference in evaluation is in most cases related to the age, lifestyle and physical activities of a given patient. In the recent years, a different approach appeared - doctors diagnose diabetes even if the blood sugar level is 5.6 mmol after a fast. Czech diabetes society recommends the following values for diagnosing diabetes: 7.0 mmol after a fast and 11.1 mmol two hours after OGTT.
If the tests confirm diabetes, other specialized examinations that focus on discovering the increased blood sugar level follow.
Patients with increased blood glucose level that is below the limit for diagnosing diabetes are diagnosed with prediabetes which can be divided into impaired fasting glucose and impaired glucose tolerance. In the case of impaired fasting glucose (IFG) the values range between 5.6 and 6.9 mmol/l of blood. In the case of impaired glucose tolerance (IGT) is the plasma glucose level between 7.8 and 11.0 mmol/l of blood after OGTT.
Nowadays, there are many precise portable glucometers available on the market and people can log their blood glucose level continuously. We have to stress that the test must be taken under certain conditions in order to get valid data. First of all, the test must be taken right after waking up, the person taking the test mustn’t be emotional or perform physical activity. The measuring also mustn’t be done sooner than after an 8-hour fast. Fever or stress can skew the results significantly and doing the test under these conditions is pointless. This measuring can find out if the liver produces more blood sugar than necessary. If the blood glucose level is higher than 5.6 mmol repeatedly, it is necessary to see your doctor and ask for an examination by a diabetologist.
Other complications related to diabetes
Diabetes can result in many complications: cardiovascular diseases (heart attack, stroke, arterial diseases), damaged kidneys, nerves, eyes and legs (diabetic foot). Underestimated diabetes caused by a lack of self-discipline can result in blindness, leg amputation, kidney failure (dialysis is required), apnoea or tooth problems. Combination of stress, overeating, unhealthy diet and insufficient physical activity lead to obesity that is often increased by higher doses of insulin than necessary. The induced hypoglycemia forces the patient to consume more sugar which increases energy intake. A higher number of insulin molecules inevitably leads to increased production of storage fat. Diabetes in combination with alcohol is lethal.
Long-term studies show that diabetics are more prone to atherosclerosis which makes diabetics also more prone to ischemic heart disease including acute myocardial infarction. This is ascribed to a change in the ratio between individual lipoprotein particles labeled as LDL, VLDL and HDL. Because this topic is quite complex, we will only say that the amount of HDL (desirable particles) decreases and the amount of LDL (undesirable particles) increases. As a result the concentration of LDL-cholesterol increases and cholesterol deposits in blood vessel walls increase quickly. Because of that almost one half of treated diabetics show verifiable changes in vessels of legs.
Available methods of treatment
Treatment depends on the diabetes type. In the case of type 1 diabetes, insulin or an analogue is administered. In the case of type 2 diabetes, lifestyle and diet are modified and physical activity and regular eating of at least 5 to 6 meals a day are important as well. The diet modification lies in regulation of carbohydrate intake according to their glycemic index and most importantly, regulation of intake of simple sugars. Appropriate physical activity affects the illness desirably and significantly. Diabetics should create their diet with exchange units in their minds.
The website www.kerbet.com is worth mentioning. This “seeming” slimming site offers quality menus suitable for diabetics for free. The big advantage of this website are exchange units and furthermore, the recipes suitable for diabetics bear a “SUITABLE FOR DIABETICS” seal. The site also offers menus created specifically for diabetics. Another valued features of the site are the content of simple sugars of each recipe and especially the visual representation of sugar content in a meal in relation to needs of a particular person.