These symptoms can be divided into two categories, namely: autonomic activation and
neuroglycopenic symptoms as summarised in table 2.1.
| SYMPTOMS OF HYPOGLYCAEMIA | |
| Autonomic activation | Neuroglycopenic |
| sweating (even heavy sweating), shaking, warmness, pounding heart and increased heart rate, anxiety and shivering. | confusion, drowsiness, weakness, difficulty in speaking, loss of concentration, visual disturbances such as double vision and dizziness. |
Table 2.1. Symptoms associated with hypoglycaemia. (From reference 10)
Many of these symptoms can manifest themselves at night or early in the morning, in view of the abstinence from food during this time, and therefore insomnia, fear and even hallucinations can be additional symptoms. The normal range of blood glucose levels should be between 80-120 mg/100ml in the morning before a good meal. After a meal, the blood sugar level will rise but should drop to this range within a few hours. Unfortunately, modern lifestyles can have a detrimental effect on the maintenance of normal blood sugar levels, and refined foods and certain stimulants are some of the main culprits.
Refined foods are used extensively in the food industry, and many processed foods as well as the myriads of sweets, cookies and soft drinks on the market contain large amounts of hidden sugars, mostly in the form of sucrose. When these foods are consumed, most of the sucrose will rapidly be converted to glucose and fructose, thus causing a glucose surge. Some of the sucrose will even enter the bloodstream unaltered and will be treated as a foreign substance as there are no enzymes to break it down outside the intestinal tract. Moreover, caffeine, which is found in tea, coffee and many soft drinks, as well as theobromine that is found in cocoa and cocoa products such as chocolates, also induce hypoglycaemia as they stimulate the conversion of stored glycogen to glucose which in turn leads to insulin release and subsequent hypoglycaemia.
The modern trend to drink large amounts of soft drinks, can prove particularly hazardous, as these contain very high levels of sugars. Although soft drink firms add only sucrose to their drinks, these beverages also contain large amounts of glucose and fructose. This anomaly is brought about by the high acidity of these drinks, which encourages acid hydrolysis of sucrose. As both glucose and fructose are less sweet than sucrose, the companies compensate for this by adding more sucrose, and an average carbonated beverage can contain as much as 136g/l of sugar11 which is more than ten teaspoons of sugar per 340ml can.
Avoidance of high sugar drinks, caffeine and theobromine together with the consumption of whole foods such as unrefined grains, legumes, fruits and vegetables will prevent hypoglycaemia. The presence of soluble fibre in these foods ensures a slow release of simple sugars over a period of time, thus preventing the glucose surge associated with refined foods. Surge releases of insulin will also be avoided and in addition the whole foods come prepacked
with the essential vitamins (particularly the B-group) and minerals required for their effective metabolism. People suffering from hypoglycaemia should also include more of the high energy whole foods, such as unrefined grains and legumes in their diet, because oats and bean products contain high levels of soluble fibres which offer protection against hypoglycaemia. It is not necessary to give up one’s sweet tooth, but one should encourage the use of naturally sweet foods, such as dates and raisins as sweeteners, and avoid large amounts of refined sweeteners which consist largely of empty calories. In table 2.2. the chemical composition of some of the most common sweeteners, as well as foods with added sugar, is presented.
Table 2.2 The composition of selected sweet foods, drinks and sweeteners. The figures are for 100g portions. (Adapted from reference 12)
It is noteworthy that none of these sweet foods contain any appreciable amounts of fibre, and they are also vitamin poor. If these items are to be used, they should be used sparingly and preferably in conjunction with foods rich in soluble fibres such as fruits, grains and legumes. It should also be noted that brown sugar, molasses, honey and jams do at least contain some vitamins and minerals, whereas the refined products do not. In most countries in the Western world the consumption of sugar is somewhat above 100g/person/day or more than 15% of the daily caloric intake.13 Obviously, this is far too high, and in view of the problems associated with such a high sugar intake there has been a move away from sucrose in certain health circles, and consumption of fructose is recommended in the place of sucrose. Fructose is often considered to be the perfect substitute for sucrose as it is natural fruit sugar. Pure fructose is, however, also a refined sugar and can cause similar conditions as sucrose.
Fructose consumption does not lead to as high postprandial glucose surges as does the consumption of sucrose, and so it does seem to have some advantages over the consumption of sucrose. It does, however, lead to increases in LDL cholesterol levels, and some researchers have also found that it will increase the levels of triglycerides.14,15 Fructose loads will also induce hypoglycaemia because fructose facilitates the formation of glycogen.13 These facts once again underline the principle that refined foods, in whatever form, are not the most wholesome of foods and should be used in moderation. It is therefore advisable to cultivate the habit of substituting whole-food sweeteners for refined sweeteners wherever possible.