A high rise in blood sugar can damage every cell in your body. When blood sugar levels rise too high, sugar can stick to the surface of cell membranes. Once stuck there, it can never get off. In a series of chemical reactions, glucose (the only sugar that circulates in your bloodstream) is converted to another sugar called fructose and eventually to a sugar alcohol called sorbitol that destroys the cell to cause every know side effect of diabetes: blindness, deafness, heart attacks, strokes, kidney damage and so forth.
When you eat, sugar can go into:
• your muscles, to make you a better athlete and prolong your life,
• your brain, to keep you smart and alert, or
• your liver to store sugar for future use. Sending too much sugar to your liver can make you fat, increase your risk for a heart attack and shorten your life.
At rest, your brain requires more sugar than the rest of your body combined. Ninety-eight percent of the energy to fuel your brain comes from sugar, so your brain has to have sugar available all the time. A constant supply of blood sugar to your brain helps keep you smart and alert. If your blood sugar level drops too low, you pass out, so your liver always tries to protect you from low blood sugar levels. When blood sugar starts to drop too low, your liver works to save your brain by releasing stored sugar from its cells into your bloodstream. If not enough sugar is available, the liver converts protein into sugar to keep your brain supplied.
Resting muscles are passive and can draw sugar from the bloodstream only with the help of insulin. Contracting muscles can remove sugar directly from the bloodstream without needing insulin. Contracting muscles are also extraordinarily sensitive to insulin, so it takes far less insulin to supply your muscles with sugar during exercise. These beneficial effects are maximal during exercise and for up to an hour afterward and then taper off to zero about 17 hours after you finish exercising.
When your muscles are inactive, you should avoid sugar and all refined carbohydrates. When your blood sugar rises too high, all the extra sugar goes to your liver, and that's when you damage your health. The high rise in blood sugar causes your pancreas to release huge amounts of insulin. This increases risk for a heart attack because insulin constricts arteries leading to your heart to block blood flow there. Insulin converts sugar to triglycerides and your blood fills with this fat (high triglycerides). High triglycerides increase risk for clotting, so your body tries to protect you by using the good HDL cholesterol to carry triglycerides from your bloodstream to your liver (low good HDL cholesterol). The increase in triglycerides can cause liver damage (fatty liver). Insulin also causes the extra fat to be deposited into fat cells in your belly (fat belly). Full belly fat cells block insulin receptors to make the blood sugar and insulin levels rise even higher.
People who have small buttocks are most likely to deposit fat in their bellies and are at the highest risk for diabetes and heart attacks. If you have a fat belly and small hips, you already have insulin levels that are high enough to cause severe damage to your health and are at high risk for diabetes and heart attacks. The combination of high blood insulin, triglycerides and sugar, low good HDL cholesterol and deposition of fat in the belly is called Metabolic Syndrome which means you are at high risk for diabetes and heart attacks. It happened because you eat too much sugar and refined carbohydrates when you are not exercising.
On the other hand, taking sugar when you exercise is good for you. I'll explain why in the next blog post.