THE PREVALENCE OF LOW BLOOD SUGAR
Personal observations since 1937 have convinced me of the frequency of low blood sugar in children, adolescents, and adults. I have performed hundreds of glucose tolerance tests routinely on patients attending a medical clinic for disorders and diseases common in everyday practice. I found evidence of low blood sugar in more than half the cases. I found that a diet aimed to correct low blood sugar did away with or greatly alleviated many symptoms not only in those who showed low blood sugar with the tolerance test but also in those who did not reveal low blood sugar at the time. I also found that an individual may show normal blood sugar levels on one occasion and low blood sugar on another occasion. I have concluded that any human can experience low blood sugar as long as he or she consumes sugar and starch. Other researchers have shown how the blood sugar level is controlled by what one eats.
Many healthy people have symptoms of low blood sugar without realizing that the symptoms are due to low blood sugar. For example, many individuals experience a physical let-down in their daily activities around 11 A.M. and 4 P.M. At those hours they get a little tired, may have a slight headache or a sensation of lightheadedness, become a little moody or depressed or irritable, and usually are hungry, especially for something sweet to serve as a "pick-up." And so they will usually partake of the following: a cup of coffee or tea or chocolate, pie, cake, pastry, cookies, candy bars, ice cream, soft drinks, or the like. These sweet foods and beverages afford a rapid relief from their symptoms because they cause a rapid rise in blood sugar level.
I regard as artificial the rapid rise in blood sugar produced by eating sugar. The sugar is an artificial stimulant; and in some people the desire for sweets amounts to a craving, and the demand for something sweet during this craving amounts to an addiction. I regard this craving for sweets as abnormal.
In the first place the low blood sugar is abnormal and could have been prevented. However slight, it is abnormal and is caused by a dietary error, namely, the ingestion of sugar and starch. The low blood sugar that comes on around 11 A.M. is due to eating sugar and starch at breakfast, and the low blood sugar at 4 P.M. is due to eating sugar and starch at the noon meal. On a high protein low carbohydrate diet the fall in blood sugar at 11 A.M, and 4 P.M. does not occur and so there is no physical let-down and no need for a pick-up. Cigarette smoking can also serve as a pick-up because nicotine can cause an immediate rise in blood sugar level by stimulating the adrenal-sympathetic system, the rise occurring at the expense of liver glycogen.
The physical and mental pick-up which follows eating something sweet is accompanied by a rise in blood sugar which lasts for about 30 to 60 minutes and which is soon followed by another fall in blood sugar. A vicious cycle is thus set up.
This rise and fall in blood sugar may occur several times during the waking hours and, as a result, many individuals acquire the habit of drinking 4 to 10 cups of coffee or tea or cocoa daily, or they eat candy at frequent intervals, or drink 4 to 10 bottles of soda pop, or find it necessary to smoke at frequent intervals. The desire for a cigarette actually coincides with a fall in blood sugar and the feeling of satisfaction that comes with a smoke is due to a rise in blood sugar. Denicotinized cigarettes do not satisfy because they do not cause a rise in blood sugar.
Coffee, tea, cocoa, not only cause a rise in blood sugar by reason of the added sugar, but also because they contain caffeine or related chemical compounds that stimulate the adrenal-sympathetic system and thus cause a rise in blood sugar at the expense of liver glycogen. People who smoke a great deal and drink much coffee and who have poor appetites are in a chronic state of malnutrition because they are steadily depleting the liver glycogen stores and are failing to replenish the stores with proper food.
Many people are irritable in the morning before breakfast because of low blood sugar. Some people are so irritable, moody, morose, or depressed, before breakfast that they dare not say anything or do anything until they have had something to eat, if only a cup of coffee. They have learned that they are more tolerable after having eaten something. The blood sugar usually reaches its lowest level in the morning before breakfast, especially after the all-night fast. I have found that eating less sugar and starch at dinner the night before helps prevent low blood sugar in the morning. (See Fig. 13.)
The effects of low blood sugar on morning behaviour and mood is profound. It is a matter of common knowledge that individuals who are irritable and cranky and prone to start arguments before breakfast experience a remarkable change after they have had something to eat. Mothers know that an irritable, cranky, and crying infant is usually a hungry infant. And most wives know that a grumpy husband will feel better after he has had something to eat. It is of great advantage to the wife and mother to know that the blood sugar level is fundamentally related to the behavior of husband or child. Having this knowledge she will readily excuse misbehavior in hungry members of the family. Thus much domestic friction can be avoided.
Statesmen are learning that properly fed citizens are happier, more satisfied, and easier to handle; and that poor nutrition and starvation go hand in hand with unrest, violence, and rebellion. The stability, behavior, and morale of a nation is the sum total of the stability, behavior, and morale of its individual citizens. A properly fed people is a healthy people.
Errors in judgment in all lifes activities are often due to the fact that the individual made a decision during a period of low blood sugar at which time he may have been moody, irritable, depressed, or unstable. I have schooled myself never to make an important decision in the morning before breakfast because my frame of mind may be such as to lead to a decision that I would later regret having made. I therefore always delay making a decision until after I have had a good breakfast.
It is surprising how ones attitude toward a problem or a person can change after a good meal, and this only because a rise in blood sugar brings about better brain function by increasing glucose-oxygen consumption. Thus decisions are more likely to be correct when made after a good meal. Experienced negotiators in business and government have
Course of the blood sugar between the hours of 11 p.M. and 6 A.M. in a patient who had hypoglycemic symptoms around S to 6 A.M. Note gradual fall during sleep to the low level of 50 mg. at 6 A.M. Symptoms were readily controlled with a low carbohydrate diet.
learned that the dinner table is a good place to accomplish things.
I have digressed somewhat merely to point out that low blood sugar can happen to everybody, at any age, and often because we all eat sugar and starch.
I have found that low blood sugar is found just as frequently in children as it is in adults. Since both children and adults may have low blood sugar, how is it that polio attacks children so much more often than adults? There is an answer to this question.
Dr. S. B. Wortis of New York found that, weight for weight, the nervous tissue of the young in any species consumes more oxygen, i.e., needs more oxygen, than that of the adult. For this reason, the nervous tissue of the young is more vulnerable to low blood sugar than that of the adult. As has been previously mentioned, nervous tissues consume oxygen in proportion as they utilize glucose. Therefore, in the presence of low blood sugar, the tissues will consume less oxygen and so suffer an oxygen lack. Periods of low blood sugar mean periods of reduced oxygen consumption with resultant increased susceptibility to infection.
Polio may strike children and adolescents who are in apparent good health, i.e., individuals who have no complaints or symptoms, and who eat and sleep well. They may have a history of no more illness than an occasional head cold, or sore throat, or stomach upset. Yet they contract polio. Why? Because low blood sugar can occur at any time if the individual is consuming sugar and starch. Excessive consumption of sweets during a single day, with or without physical over-exertion, may cause a period of prolonged low blood sugar which will lower protective barriers and permit the polio virus to invade the central nervous system.
Good health is not something one is born with and which persists from year to year as a permanent physical characteristic. Good health is largely the result of bodily chemical conditions which fluctuate normally at every moment within a narrow range. The range of fluctuation is controlled by several factors, especially diet and physical activity. And one of the most important chemicals is the blood sugar. To a great extent, then, health will depend on the fluctuation range of the blood sugar. Good health thus becomes a condition which is at any moment dependent on labile (unstable) chemical states in the blood and tissue fluids, and which may be lost or impaired temporarily when the chemical equilibrium is upset. If an individual is able to eat regularly a diet adequate in quantity and quality, indulge in normal physical and mental activity, and get adequate rest and sleep, he may be reasonably assured of continuing good health. Some individuals seem constitutionally healthier and sturdier than others, but they are only relatively so. Healthy and sturdy individuals can succumb to disease very readily when they are under stress, when they become careless in dietary habits, and when they over-exert physically or mentally.
Several observers have remarked on the fact that polio frequently attacks children and adolescents who are larger and heavier than the average for their age. Some of them are actually obese. I would say that such individuals eat excess amounts of sugar and starch and the excess is laid down in the bodys tissues as fat. Such individuals often have an inordinate craving for sweets and starches; and it is their excessive consumption which causes low blood sugar and subsequent susceptibility to polio.
I have had frequent occasion to observe and treat many adolescents who came to me complaining of symptoms which were found to be due to chronic low blood sugar as determined by the sugar tolerance test. That their complaints and symptoms were due to low blood sugar was confirmed readily by the fact that they were relieved by the elimination or drastic reduction in the consumption of sugar and starch. Individuals with chronic low blood sugar are particularly vulnerable to invasion by the polio virus. As I mentioned previously, the appearance in the clinic of individuals who had had polio several years before and who were now complaining of symptoms that proved to be due to low blood sugar, led me to suspect that there might be some connection between low blood sugar and susceptibility to polio.
I shall now cite several case histories of adolescents with chronic low blood sugar whom I have observed and treated. The reader will thus get an idea of the many and varied complaints that such individuals have. I want to emphasize that such cases are by no means rare; they are seen frequently in clinics. I shall give the results of the sugar tolerance test in each case. In this test the individual, in the fasting state in the morning, drinks a solution containing 50 grams of glucose. A blood sugar specimen is taken immediately before the solution is drunk. Blood sugar specimens are then taken one half hour, 1 hour, 2 hours, 3 hours, and sometimes 4 hours after the solution is drunk. You will notice that in each case the blood sugar was well below the lower limit of normal of 80 mg. at some time during the test. The duration of low blood sugar varied in each individual but in each case it lasted for a significant period of time.
Case No. 1. J. D., male, 13 years old, was brought in by his mother who stated that he was listless, had no desire to play with other boys, had no desire to do his school homework, and preferred to rest most of the time. She had much difficulty waking him from sleep in the morning. A year before he had a fainting spell while in church. Physical examination of the boy revealed moderate underweight but no physical abnormalities. He ate fairly well and consumed average amounts of sugar and starch. A sugar tolerance test revealed: fasting blood sugar, 78 mg.; ½ hour, 115 mg.; 1 hour, 55 mg.; 2 hours, 46 mg.; 3 hours, 58 mg. On a high protein diet with reduced consumption of sugar and starch he improved within a few weeks.
Comment. This case may be regarded as a severe example of chronic low blood sugar. His fasting blood sugar was practically normal and he showed a rise 1/2 hour after taking 50 grams of glucose. However, for the next three hours the blood sugar remained at low levels. Apparently at the time of his fainting spell a year before, the blood sugar had fallen to a level much lower than 46 mg. which he had at the end of 2 hours.
Case No. 2. A. Z., male, 12 years old, came in complaining of daily generalized abdominal rumbling of several months duration. The rumbling was felt in the morning before breakfast and disappeared after food was taken. It recurred about 15 minutes after breakfast was eaten and would last practically all morning at school until lunch was taken when it disappeared again. Soon after lunch, on his way to school, it would recur and keep up till 3 P.M. when he took a glass of milk which afforded relief. It soon recurred and kept up till supper when it was relieved by eating. It reappeared shortly after supper and lasted till he fell asleep. Sleep was sound. Physical examination revealed no physical abnormality. He was not underweight. His diet contained considerable amounts of sugar and starch with each meal.
A sugar tolerance test revealed: fasting, 60 mg.; ½hour, 100 mg.; 1 hour, 55 mg; 2 hours, 50 mg.; 3 hours, 60 mg. He was readily relieved by a high protein low carbohydrate diet after a few days.
Comment. This case illustrates one of the common symptoms caused by low blood sugar, namely, abnormal contractions of the stomach and intestinal musculature. You will note that he had rumbling before meals when his blood sugar was low and that the rumbling disappeared immediately after eating because the blood sugar rose, though temporarily. Rumbling reappeared 15 to 30 minutes after eating because low blood sugar came on again, and the rumbling lasted as long as the low blood sugar persisted. In cases of sharp abdominal pain the blood sugar level is usually even lower and causes stronger contractions of the intestinal musculature.
At this point it would be well to digress and discuss the mechanism of the normal hunger sensation because the symptoms, rumbling and abdominal pain, are actually abnormally exaggerated hunger phenomena. In an individual with normal blood sugar levels and with a normal sugar tolerance curve, the blood sugar rises to around 100 mg. after ½ hour; 120 mg. after 1 hour; 140 mg. after 2 hours, with a gradual fall during the third and fourth hours to the previous fasting level of 80 to 90 mg. (Fig. 1).
The only sensation occurring during the fall is that of ordinary hunger. The fall in blood sugar stimulates in the brainstem certain nerve centers which control stomach and intestinal muscular contractions. The fall in blood sugar serves as an automatic mechanism to inform the organism that it is time to eat. As a result, the stomach starts to contract rhythmically and vigorously and the sensation of hunger is felt. Normal hunger thus depends on a gradual fall in blood sugar within the normal range. Abnormal hunger and hunger pangs are due to abnormally strong gastric (stomach) contractions brought on by a too rapid fall, especially when the fall is to abnormally low levels. Not only is the stomach stimulated, to strong contractions by the low blood sugar, but also the intestines; and the strong contractions of the latter give rise to generalized rumbling and pain and cramps.
Thus, in case No. 2, the patients generalized rumbling was actually an abnormal exaggeration of a normal physiologic function, namely, the hunger mechanism. This patients blood sugar would rise briefly and then start to fall to low levels, causing strong contractions of the stomach and intestines. Instead of rising steadily during the first two hours to around 140 mg., the blood sugar rose to 100 mg. at the end of ½ hour, and then fell to 50 mg. at the end of one hour; and it was during this fall that his rumbling would begin and keep up till he ate some food, when the rumbling disappeared coincident with a rise in blood sugar. If the blood sugar had fallen to 40 mg. the stomach and intestinal contractions would have been more violent and would have given rise to sharp abdominal pain or cramps.
Case No. 3. F. M., male, 13 years old, was referred to the clinic by a school physician for failure to gain weight, frequent headaches, restlessness, nervousness, and "fidgeting" in class. He also had attacks of sharp abdominal pain at irregular intervals. These attacks would come on about 15 minutes before a meal, causing him to double up. He had no nausea, vomiting, or fever with the attacks. He also tired easily on ordinary exertion. His mother stated that the boy had had a "nervous breakdown" at the age of 9 years. Physical examination revealed a thin, pale boy, with no evidence of physical abnormality. His diet contained much sugar and starch.
A sugar tolerance test revealed: fasting, 65 mg.; ½ hour, 90 mg.; 1 hour, 75 mg.; 2 hours, 55 mg.; 3 hours, 50 mg. He responded readily to a high protein low carbohydrate diet. His nervousness and abdominal pain were relieved after a week on the diet and after a few months he showed a gain in weight.
Comment. This patients symptoms were chiefly nervous in origin. This is to be expected, since the nervous system is very vulnerable to low blood sugar, especially in the young. The fact that his attacks of abdominal pain came on before meals is a clue that they were most likely due to periods of low blood sugar. His response to the change in diet confirmed this suspicion.
Case No. 4. B. P., male, 14 years old, was brought in by his mother because of nervousness, dizzy spells, frequent headaches, night sweats, and abdominal pain after hard running (a "stitch in the side," as boys commonly call it). He also had frequent attacks of coldness and blueness of the hands and forearms in cold weather and even in moderate weather. The mother also stated that he was cranky, easily angered, and "always wants to eat," especially something sweet. Because the family was poor, the diet consisted chiefly of the cheaper starchy foods. He also ate excessive amounts of sugar. Physical examination revealed a nervous, restless, alert, thin boy. There were no physical abnormalities.
The sugar tolerance test revealed: fasting, 75 mg.; ½hour, 100 mg.; 1 hour, 90 mg.; 2 hours, 60 mg.; 3 hours, 60 mg. Financial difficulties prevented giving him the prescribed high protein diet but he did improve considerably by reducing the consumption of sugar and starch.
Comment. This case illustrates the abnormal craving for food, especially sweets, in the presence of chronic low blood sugar. The low blood sugar causes frequent and strong stomach contractions which give rise to frequent hunger sensations. In this case, although the consumption of sweets was excessive, the boy was not overweight. (In other cases, where there may also be some disturbed function of the endocrine glands (thyroid, pituitary, pancreas) the excessive consumption of sugar and starch may lead to obesity). As has been stated, irritability is a common symptom of low blood sugar. This boy was very cranky, easily provoked, and subject to temper tantrums. Low blood sugar readily explains the irritability that accompanies marked hunger.
Case No. 5. J. S., male, 11 years old, was brought in by his mother because he was thin, overactive, and a poor eater. He also had attacks of numbness and coldness of the hands. Occasionally he had chills soon after eating. He had frequent attacks of upper and lower abdominal pain on exertion, such as running. He often felt dizzy on getting up from the lying position. Physical examination revealed an alert, thin, intelligent boy with no physical abnormalities. A sugar tolerance test revealed: fasting, 80 mg.; ½ hour, 80 mg.; 1 hour, 95 mg.; 2 hours, 75 mg.; 3 hours, 55 mg. With a change to a high protein low carbohydrate diet he had prompt relief from the abdominal pain and showed improvement with respect to his nervous complaints.
Case No. 6. R. S., male, 15 years old, came in because of failure to gain, frequent head colds, headaches, restlessness at school and at the movies. Apparently he was unable to remain seated for any length of time. He was a chronic fingernail biter. Physical examination revealed a thin, nervous boy with no evidence of physical abnormality. Because of financial difficulties his diet consisted chiefly of the cheaper starchy foods. The sugar tolerance test revealed: fasting, 75 mg.; ½ hour, 85 mg.; 1 hour, 68 mg.; 2 hours, 68 mg.; 3 hours, 68 mg.
Comment. This boy showed a very slight rise to 85 mg. at the end of ½ hour, and for the next 2½ hours the blood sugar was maintained at the low level of 68 mg.