Sugar coating -- the very words produce an image for most of us, of something yummy.

But what if you thought of your blood cells as sugar coated? "Like a glazed donut," says Dr. Robert J. Tanenberg. And not just your blood cells, but your kidneys, liver, eyes, nerve cells . . . and more.

Dr. Tanenberg, an internist specializing in endocrinology and diabetes control and a clinical assistant professor of medicine at Georgetown Medical Center, sees the ravages of diabetes in just that way. And if its 10 million estimated victims in this country could picture the "glazing" of their internal organs as vividly as does Tanenberg, he feels the often fatal complications of the disorder could be greatly lessened.

Up until the 1920s, a diagnosis of diabetes was a death sentence. And a pretty swift one, at that. It is probably one of man's earliest afflictions. Its symptoms were described by Egyptians as early as 1500 B.C. No one knows what causes it, for sure, although some research indicates a viral connection. There is no cure, no way to prevent its onset.

With the discovery of insulin a mere half century ago, a diabetic could expect after long last a prolonged life.But even as life was extended, it became apparent that diabetics were prone at a much greater rate than the public at large to a series of complications, including:

The gamut of vascular diseases -- strokes, heart attacks and poor circulation to extremities leading eventually to the dread gangrene, amputations and death.

Blindness from a variety of eye disorders. Diabetes is the leading cause of new blindness in this country.

Kidney failure.

Complications in pregnancy threatening both mother and infant.

Diabetes, apart from its complications, is the fifth leading cause of death in the U.S. Adding deaths from complications, it jumps to third.

Many specialists in the disease believe it need not be so davastating. It is, they believe -- and Dr. Tanenberg is of this school -- mostly a matter of control.

Of course, research into the cause of diabetes and eventually its permanent control, even prevention, continues at a considerable pace, aided greatly by this decade's explosion of knowledge in cellular biology, biochemistry, endocrinology and all other details of the body's intricate physiological functions scientists are only just beginning to fathom. i

And it is no real surprise that there has been controversy on treatment, in approaches to control and conflicting opinions as to why a given diabetic will be susceptible to a particular complication.

More and more, though, says Dr. Tanenberg, evidence supports the thesis that it is the sugar coating itself -- the elevated blood sugar, the blood cells and other internal workings glazed with sweetness -- that wreaks the principal havoc.

It follows that tight control of the elevated blood sugar should avert the life-threatening complications.

The problem for diabetes specialists always has been how to accomplish this control and how to provide a way for the patient to maintain it. Diabetes is chronic and capricious. In juveniles it is mostly a matter of a pancreas disorder in which not enough insulin is manufactured to properly process sugar in the system. Somehow the message to the pancreas, normally triggered by elevated blood sugar levels, is short-circuited.

In the kind of diabetes that occurs in later life, often in the obese, it has been found that the breakdown is in utilizing the insulin. Often weight loss will completely alleviate the problem. Some doctors, in fact, regard this disorder as something other than true diabetes. However, when weight is regained, blood sugar levels rise. Because the resulting damage is the same -- no matter why it happens -- specialists continue to regard this disorder as adult onset diabetes.

In the early days of insulin injections, syringes were crude and measurements approximate. The paraphernalia for the diabetic is now sophisticated and greatly simplified. But until recently there has been no accurate way to provide insulin at the moment it is really needed -- when the blood sugar is high.

Elaborate equipment exists, says Dr. Tanenberg, but it is clumsy and expensive beyond the means of the average patient.

However, now there is a simple home blood test, called Chemstrip, which can provide the needed information in minutes. Dr. Tanenberg, who used it with his patients on an experimental basis, found it particularly helpful for diabetics on insulin. For about 50 cents a shot, patients and physicians can keep a tight control with less fuss, fewer office visits and more successful results than had been available before.

The kit, developed by Bio-Dynamics, Inc., comes complete with a minuscule sterile sticker, alcohol, gauze and the chemically treated strip. In a virtually painless process one drop of blood is obtained and spread on the strip. After two simple procedures and a total elapsed time of two minutes, the strip can be compared to a color chart and the blood sugar level accurately gauged. Then the precise dose of insulin may be given at the moment it is needed.

Monitoring is the basis of successful control of diabetes which is always a matter of keeping the system in proper balance. Dr. Tanenberg, also the physician-vice president of the American Diabetes Association, is engaged in a variety of activities designed to educate -- both doctors and patients as well as families of diabetics. His own patients range in age from toddlers to nonogenerians. During summers he is a medical consultant to Camp Glyndon, a camp for diabetic children -- and at times their families -- in Maryland.

The area chapter of ADA itself provides a variety of services: diabetic cookbooks for specialty tastes. It is preparing a local directory for medical specialists who also specialize in diabetic patients -- obstetricians, or cardiovascular specialists, or opthalmologists for example.