A Power Program for Student Review
Course Coverage 2016
- Jan Fit To Last
- Feb Urbanized Eating
- Mar Mind & Memory
- April Special Senses
- May Metabolic Syndromes
- June Sugar Diabetes
- July Diabetes Complications
- Aug Cholesterol, Atheroma
- Sept Tests & Treatments
- Oct Stress & Strain
- Nov Cancer Considerations
- Dec Aging Gracefully
June’s teaching focus was on Diabetes…a metabolic disorder that involves much more of a metabolic disorder than simply the blood sugar. It can complicate pregnancy, surgery, infections, trauma, even survival. A spectrum of common clinical presentations of Diabetes is reviewed in this Countdown….
Diabetes has been a problem for humankind from antiquity, and known for centuries as The Pissing Disease from its conspicuous expression in thirst and urination. Physicians of ancient Greece examining the urine of such patients found it sweet to the taste and named it the Sweet Pissing Disorder, or Diabetes Mellitus. An elevated blood sugar is its hallmark and indicates one failure of the normal insulin effect.
Insulin’s task is to transfer nutrients like glucose and amino acids into the body’s tissues after a meal. It is a hormone, made in the pancreas. It enters portal vein blood and flows up into the liver, an organ that receives all nutrients from digestion to process them for distribution to body parts. Normally, the liver sweeps randomly released insulin up from the portal vein, and out of the circulation. But when choked with fat (common today with visceral obesity) liver cells allow insulin to circulate in the blood to excess. It’s target tissues (muscle and fat) resist being overfed by high blood levels, and insulin’s effect is dampened. Nutrient transfers are delayed, and a state of insulin resistance exists. The patient has few or no symptoms at this time, but a persistent nutrient back-ups make metabolic processes stiff and slow. Clinical diabetes is on the horizon.
Diabetic keto-acidosis is the metabolic crisis from burning excess fat. Because sugar cannot be burned, blood levels rise while the body’s energy needs are met by burning more and more fat. This produces incompletely burned fat which ‘smokes’ forming combustion products collectively known as ketone bodies. They depress consciousness and provoke hyperventilation. The patient is heading for the coma of keto-acidosis. Insulin and fluids are lifesaving. Thousands of units of insulin and dozens of liters intravenous fluids may be needed.
A second kind of diabetic coma can result from simple severe dehydration. Called hyperosmolar diabetic coma, it does not cause keto-acidosis and patients do not hyperventilate. Usually seen in an elderly individual living alone during a summer heat wave, he or she is often handicapped by a blunted sense of thirst, common with age. The blood sugar rises high and carries much body water away in the urine which dries the patient out without prompting any corrective thirst. The patient’s skin and mucous membranes are dry, consciousness is depressed and the need for fluids is greater than the need for insulin. Both however, are needed for the best management.
Insulin failure can be relative or absolute, and partial or total…and differing degrees of insulin effect failure express themselves differently in the clinic. Total insulin failure is most clearly seen after surgical pancreatectomy (perhaps for cancer) or from autoimmune disease as in juvenile diabetes. The failed effect allows blood sugars to drift up, to spill into the urine and begin an excessive burning of fat for energy.
Keeping the blood sugar level where it should be is a normal liver function. During periods of fasting or starvation the liver makes sugar from proteins for body organs like the brain, and distributes its sugar through the blood. With insulin resistance and a slowing of metabolic processes, the challenge of a glucose load, called the glucose tolerance test, will demonstrate a delayed clearance of sugar from the blood. The diagnosis of early or ‘chemical’ diabetes is made. Nutrient transfers continue but at slower rates, and patients often feel well or admit to being perhaps a little less energetic. Overnight fasting blood sugars are routinely normal.
A positive Glucose Tolerance Test in a well-fed fasting patient is early diabetes, or chemical diabetes. It is not pre-diabetes. Such patients’ blood sugars are best kept low after meals with a diabetic diet that spreads complex carbohydrate intakes evenly over the day. Simple carbohydrates, like sugars, are best avoided because they are absorbed too quickly. Complex ones like starches and vegetables take more time to digest, and are preferred in the diabetic diet.
Over the years that insulin resistance slowly develops, the pancreas compensates by overproducing it. When eventually defeated, blood sugars begin drift up after each meal and fail to return to normal in a timely way, even though insulin levels are very high. When blood glucose levels exceed 180 mg % sugar begins to spill into the urine. Normal kidneys can keep it within the blood and out of the urine at levels below 180. Once sugar begins flooding the urine, patients develop classic symptoms and signs of diabetes: thirst, polyuria, fatigue, tissue wasting, debility. Without treatment they progress to coma and death.
Once newly diagnosed diabetics have their blood chemistries restored to normal, they must begin managing life in ways that avoid their blood sugars going too low or too high. Too low a sugar can lead to loss of consciousness because the brain needs it to function. Too high a sugar, while less dramatic an may not even spill in the urine, but causes tissue damage over the years. The kind of diabetes most commonly met clinically these days is called Type II. Typically, it begins with insulin resistance from the fatty liver of visceral obesity, progressing to a gradual elevation of the blood sugar when a diagnosis is made.
In summary, a metabolic disease with us from antiquity, called sugar diabetes, has become one of today’s diseases of abundance. Today it is a product of obesity from so much tasty cheap food: available 24/7, and from the physical inactivity of our digital age. It eventually cripples patients with the complications of blindness and limb loss, or it compromises their lives with heart attacks, strokes and kidney failure.BLAST OFF