The American doctor and nutritionist Carlton Fredericks, a renowned authority on low blood sugar, stated “when blood sugar drops as little as 0.25mmol/L below the normal for the patient, a profound glandular compensation may start’. However, as mentioned above, a low level of blood sugar is not the only cause of low blood sugar symptoms – an inappropriately rapid fall in the blood glucose can also give rise to symptoms.
SPEED OF FALL IN BLOOD SUGAR
A rapid fall in the blood sugar level (for whatever reason) in excess of 1.5mmol/L in one hour can produce symptoms of low blood sugar. These changes occur irrespective of the actual level of blood sugar, for example a fall from 7mmol/L to 5mmol/L in 30–45 minutes can often cause low blood sugar symptoms to develop.
Both of the trigger factors that cause low blood sugar symptoms – i.e. speed of fall and a general low level – are subject to individual variations. I have seen patients who appeared to be symptom-free with a blood sugar level of 2.5mmol/L and others with levels around 3.5mmol/L who could barely walk or talk.
Insulin-dependent diabetics can ‘hypo’ when they overdose on their insulin requirements in relation to food and/or activity. Glucometers are used to check their blood glucose levels. Early models were designed to measure high blood sugar levels, however the more recent glucometers can measure blood sugar levels as low as 1.5mmol/L with a finger-prick blood sample. Accurate results can be achieved within 6–60 seconds, depending on the model used.
The problems caused by too much sugar
The high-carbohydrate Western diet provides sugar far in excess of our energy needs. Consumption of sugar alone in Great Britain amounts to 27kg (60–65lb) per person per year. If you include the sugar-rich refined carbohydrates we eat (for example, sweets, chocolates, cookies, cakes, cereals, soda and cola drinks) then our total sugar ‘load’ can be as high as 90kg (200lbs) per person (the figures in the US follow close behind). In terms of calories, one teaspoon of sugar per day equals 100 calories per week, so the amount of calories consumed by someone at the top end of the sugar-intake scale is vast.
When we eat sugar, we either use it for energy needs, or it is stored as glycogen or fat. Marathon runners know that they need to consume extra carbohydrates three to four days before a race to provide stored fuel for gradual release during the race. Likewise, those who do heavy manual work can often avoid weight and health problems as a result of converting all their food (fuel) directly to energy.
The experience of the explorer Sir Ranulph Fiennes clearly demonstrates how important it is that we match our energy intake to our output. On an Arctic trek, Fiennes lost weight despite consuming 5000 calories a day. In spite of his high calorie diet, his energy requirements meant he utilized a total of 11,000 calories each day. His subsequent weight loss was therefore inevitable. Perhaps we could justify our high sugar diets with marathon running or polar exploration – not popular choices. Fortunately there are other solutions (these are discussed in Part Two).
Insulin
Central to the problem of low blood sugar is the hormone insulin. Any rise in our blood sugar requires an insulin response. Insulin is a hormone secreted by the pancreas to lower blood glucose levels; it does this by transporting the glucose to the muscle cells and other tissues. Insulin is uniquely the only hormone to promote food (fuel) storage for future use. For this reason it is often termed the storage or fattening hormone.
This storage facility was essential for human survival several thousand years ago, for the early hunter-gatherers were very similar to the present day big cat carnivores in Africa and India. Their eating habits consisted of large meals perhaps every three to four days. The ability to store food was therefore a vital survival strategy. Unfortunately 21st-century men and women follow a largely sedentary lifestyle yet they often eat carbohydrate-rich meals and snacks three to six times daily. Our metabolism can only convert a small amount of excessive sugar to glycogen, which is stored in the liver and muscle cells. The remainder is stored as fat. Our food is our fuel and if the fuel is not required it is stored and excess weight is the result.
However, a sugar-laden diet does not only lead to the storage of fat. Because the insulin response is constantly being overworked, it can become less efficient as the cells become less sensitive and resistant to the effect of the insulin.
INSULIN RESISTANCE
This gradual loss of sensitivity to the blood insulin results in an increase in the level of insulin as the pancreas secretes more and more in an attempt to normalize the blood sugar balance. The end result is an on-going high level of blood insulin (hyperinsulinaemia). This excess insulin promotes more fat storage at the expense of available energy. High-sugar and high-carbohydrate eating can eventually lead to obesity, high blood fats, high blood pressure and fatigue (this group of disorders is known as Syndrome X, or metabolic syndrome). Such inappropriately high levels of blood insulin can cause chronic irritable bowel syndrome, adrenal exhaustion and disturbances to the female hormonal balance (as in Polycystic Ovary Syndrome).
The adrenal response
Although the brain and nervous system rely on blood sugar as the chief nutrient, excessively high levels of blood sugar can cause damage to nerve cells.
The temporary fall in the blood sugar caused by the insulin response to food triggers adrenal compensation, where adrenaline is released to counter the effect of the low blood sugar. This yo-yoing of the blood sugar levels can lead to a chronic imbalance in the blood sugar control (dysglycaemia), causing adrenal deficiency and a reduced thyroid hormone output. The thyroid gland reflects our metabolic rate and mild hypothyroidism can result from adrenal exhaustion.
The role of the adrenal hormone adrenaline in the blood sugar narrative highlights a design fault in our body chemistry. This vital hormone has two major functions. These are stress-handling (the so-called fight or flight response) and raising our blood sugar when the level falls too low.
As any athlete knows, adrenaline increases the metabolic rate, the heart rate, the blood flow to muscles and the oxygen intake. In a primitive society this would prepare us to either run or attack. However, for those of us who suffer from low blood sugar (which causes our brain and nervous system efficiency to be compromised), the adrenaline response that occurs is identical to our reaction to any type of stress. This explains why so many sufferers of long-term low blood sugar experience episodes of aggression and mood changes – examples being women with pre-menstrual syndrome and diabetics or non-diabetics who ‘hypo’. Our metabolism cannot identify the reason for the adrenal surge, hence the stress response that occurs with low blood sugar.
Summary
The modern high carbohydrate/sugar diet, coupled with our sedentary lifestyle, has lead to an increase in many low blood sugar symptoms, including obesity, fatigue and poor stress handling. The subsequent adrenal compensation and exhaustion can result in mild hypothyroidism, high blood pressure and subsequently Syndrome X. Anxiety, depression, elevated blood fats and metabolic depression can be the consequence.
In the next chapter we look at the many symptoms that can result from low blood sugar.
CHAPTER 3 The symptoms of low blood sugar
One