Not surprisingly, health professionals treating diabetics were less than ecstatic about recent headlines proclaiming "Sugars Safe for Diabetics."
Results of experiments measuring the impact on levels of blood sugar (glucose) of certain carbohydrates can in no way be interpreted as carte blanche for routine fancy desserts or a Reeses Pieces snack, as even the researchers are quick to agree.
On the other hand, the new studies demonstrate some major medical misconceptions about the way carbohydrates affect blood sugar. And they certainly suggest an imminent shift in the way individual diabetic cases ought to be handled--not tomorrow, perhaps, but sooner rather than later.
The latest study, published in a recent issue of the New England Journal of Medicine, demonstrated that among 22 diabetic subjects tested at the University of Minnesota, simple sugar (sucrose) when ingested along with a meal, did not cause blood sugar to rise any more than did certain other forms of carbohydrates: in this case, potato starch, wheat starch and fructose (the fruit form of sugar).
Different studies at the University of Colorado Health Sciences Center have demonstrated some surprising differences between various carbohydrates and the blood-sugar levels they seem to cause. A baked potato, for example, appeared more of a villain in upsetting blood-sugar equilibrium than a bowl of ice cream.
Hence the widespread reports about "safe" sugars.
The story on simple sugars, however, is a lot more complicated than it sounds. And this is not the first time diabetologists have been caught short on the validity of their medically accepted dietary advice to patients.
Diabetes is a metabolic disorder characterized by the body's failure to properly process food into fuel and energy for the body's cells.
In Type-1 diabetes, once called "juvenile" or "insulin-dependent" diabetes, the problem seems to lie with the failure of the beta cells in the pancreas to produce insulin. It is insulin that paves the way for glucose to get into the cells that need it. Without insulin, the glucose spills into the blood and eventually shows up in the urine.
In Type-II diabetes, formerly known as "maturity- or adult-onset diabetes," there may be enough insulin made by the pancreas (in response to food taken in) but the insulin is unable to get the cells to open up to receive the glucose. So again, the sugar spills into the blood as in Type 1.
Eventually, in both types of diabetes, the sugar in the bloodstream wreaks havoc on a number of major organs, thereby leading to the complications of heart, kidneys, eyes, nerves that make diabetes the second or third leading cause of death in this country. It is a leading cause of new blindness. Diabetics also run the risk of potentially fatal coma stemming from either too high a blood sugar or too low.
An estimated 10 million Americans are diabetics, 8 million Type-II and 2 million insulin-dependent.
Type-I diabetes is controlled by a combination of insulin therapy and diet.
Type-II diabetes often responds to diet therapy alone--and often disappears with the control of obesity. In fact, Dr. Robert J. Tanenberg, an area diabetologist, believes along with many of his colleagues, that treating Type-II diabetics with insulin is a self-defeating proposition because the body is given conflicting and erroneous biochemical signals that serve to perpetuate the disorder. "You have to break the cycle someplace else" than at the insulin level , he says.
Specialists in diabetes have made enormous strides over the past decade with research into intricate biochemical activities not even dreamed of when insulin was discovered in the early 1920s, into sophisticated insulin-delivery systems and simple blood-sugar home-monitoring systems.
But they've made some mistakes along the way and some, says Tanenberg, may have caused or at least contributed to coronary complications associated with diabetes.
Part of the problem has been the continuing reluctance of the medical profession to regard nutrition as a genuine arm of medical science. As much as any single group, diabetics have suffered from this gap.
The early pre-insulin treatment of diabetes was virtual starvation. But this clearly was not satisfactory, especially when dealing with growing children.
As Tanenberg describes it, "When insulin came on board, then they all thought that carbohydrate was the fall guy . . ."
The result was that until the 1950s, diabetic specialists restricted all carbohydrates and when extra calories were needed, they encouraged fats.
"In the '20s," says Tanenberg, "nobody knew much about saturated and polyunsaturated fats, so that certainly helped to set the stage for the coronary disease we see today in diabetic patients."
Moreover, it took the specialists about 30 years to establish that the one-shot-a-day insulin therapy, instituted for the sake of convenience, was counterproductive to avoiding wide and erratic blood-sugar fluctuations, from way above normal to way below and back again. Keeping the blood-sugar level as even as possible is now seen as probably the best way to forestall eventual complications. In part this can be done by the use of home-monitoring kits and careful adherence to diet.
But what diet?
Diabetics are guided by a series of dietary "exchange" lists that attempt to categorize foods according to their nutritional classifications, revised periodically over the years to incorporate new nutritional knowledge. Gradually they have come to rely less on fats and more on complex carbohydrates, now including many high-fiber foods, newly seen as highly beneficial to the diabetic.
Karen Stone, a registered dietician and partner in Diabetic Educational Services, Inc., an independent nutritional counseling service, sees the new studies simply as an indication that "we still have a lot to learn about food and we're still at a very early stage. It was a surprise because it goes against all the principles we've been taught.
"The important thing to remember," says Stone, "is that each food's effect on blood sugar must be tested individually, one by one, both in combination with other foods and separately."
The studies also show, she notes, that blood-sugar reactions differ according to how the carbohydrates were packaged. For example, wheat in pasta had less of an effect than wheat in bread.
Stone also warns that even if a particular simple sugar did not have an immediate effect on blood sugar, "there is no information about its long-term effect . . . and besides, you have to think about the more nutritious item it might be displacing."
"Basically," both Stone and Tanenberg agree, "all this proves is that we have got to run a lot more studies."