The Physiology Of Low Blood Sugar
When the blood glucose level drops, the adrenal glands are stimulated to release epinephrine (adrenaline). The epinephrine, in turn, stimulates the pancreas to release glucagon. Glucagon stimulates the liver and muscle to convert the glycogen--the storage form of glucose--back to glucose. The liver releases this glucose into the blood. This results in a temporary rise in the blood glucose level. If the person does not eat within an hour, the adrenals start releasing cortisol. Cortisol stimulates the breakdown of muscle tissue and the release of the amino acids into the blood. The liver takes up some of the amino acids and converts them to glucose. The amino acids the liver cannot convert to glucose are broken down, and the by-products are excreted by the kidneys. If the conversion of amino acids to glucose cannot maintain an adequate blood sugar level, fat stores are eventually accessed for energy. Fatty acids are the preferred fuel for the liver. The muscle, however, only uses fatty acids when there is insufficient glucose to support its energy needs. This mechanism of maintaining energy is secondary to glucose, and only happens if the necessity arises.
 

Timing Of Meals And Snacks
Many people make the mistake of skipping meals. Frequently, they skip breakfast because they "are not hungry in the morning," and they skip other meals in an attempt to lose weight. Unfortunately, skipping meals results in low blood glucose, and frequent low blood sugar can be the stimulus for a cascade of health problems.

In general, eating breakfast within an hour of getting up in the morning is ideal. The body has gone all night without any food, so the blood glucose level in the morning is very low. After breakfast most individuals must eat a meal every four to five hours or their blood glucose level drops. If they eat only a small amount of food, such as a snack, they will need to eat again two to three hours after the snack.

All snacks also must be a combination of protein, carbohydrate and fat. For example, a good snack would be a medium-sized apple and 2 ounces of low-fat cheddar cheese. You get the protein and fat from the cheese, and the carbohydrates from the apple.

Maintaining an adequate blood sugar level is not only important for optimal energy and mental function, but it also greatly reduces the stress on other organ systems in the body. (See sidebar on Page 30.) Frequent low blood sugar can greatly increase the workload for the liver, adrenals and kidneys. The cortisol stimulated by the low blood glucose level causes suppression of the digestive function and the immune system. Consistent rises in cortisol will contribute to reduced bone density and osteoporosis. The breakdown in muscle stimulated by cortisol results in decreases in lean body mass, but not the body fat. As the lean body mass drops, so does the metabolic rate. The metabolic rate is the rate at which the body uses the energy from food. A lower metabolic rate makes it easier to gain weight and more difficult to lose weight.

The blood glucose level is also used by the body to help predict the possibility of future starvation. Unfortunately, the body cannot distinguish between a person choosing not to eat and actual starvation. Many people diet by eating only one large meal each day. This meal is usually at dinner time, thus they go through most of the day with low blood glucose levels. The blood sugar/starvation monitoring mechanism is so fine-tuned in some individuals that everyday periods of low blood sugar cause the body to react as if it is going into a period of starvation. Remember, fat is the only long-term energy store in the body. So when the dieter finally eats that one big meal, the body very efficiently takes any extra calories and readily converts them to fat. That way there will be sufficient energy stores to prevent possible starvation.

After years of skipping meals and/or dieting, many individuals develop chronic health problems, all resulting from frequent low blood glucose. An overworked pancreas can result in adult onset diabetes. Excess cortisol and overworked adrenals contribute to osteoporosis, sleep disturbances, menopausal difficulties in women, poor immune function, resulting in frequent colds and flu, and general malnutrition due to suppressed digestive function. As a result of this general malnutrition, muscles, tendons and ligaments tend to injure easily and heal poorly.

Quality Time For Meals
Rushing through meals and eating on the run are a way of life in our society. Unfortunately, these lifestyle habits have a negative impact on the digestive function, in particular, and the quality of health, in general.

Digestion requires the action of the parasympathetic nervous system. This is the part of the nervous system that handles resting and digesting. Driving through traffic, rushing through breakfast to get to work on time, or watching a suspenseful movie all stimulate the sympathetic nervous system. The sympathetic nervous system is the flight or fight part of the nervous system. When the sympathetic nervous system is stimulated, the parasympathetic shuts down. Given this scenario, how well do you think the digestive system works while rushing, driving or watching a movie thriller? Not very well.

Taking time to eat in a relaxed environment can do wonders for the digestion and absorption of nutrients, which, in turn, will improve healing time and optimize health.

In the next article, we will discuss the all-important micronutrients (vitamins and minerals) and how they fit into the picture of nutrition.

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Joy Bicknell, MS, CNS, has been working in alternative health care for more than 15 years. She has a Master of Science in Human Nutrition, and is a Certified Nutritional Specialist. She may be contacted at: joynutrition@attbi.com.

Ben E. Benjamin, Ph.D. in sports medicine and education, is the founder and president of the Muscular Therapy Institute in Cambridge, Massachusetts. If you wish to purchase a bound copy of the entire article series, E-mail Ben@mtti.com, or write to Benjamin at: 175 Richdale Ave., #106, Cambridge, MA 02140.