Since the 1940s, North Americans have suffered an incredible increase in disease. Today, 70 percent are overweight, 35 percent become diabetic, 40 percent die of heart attacks, and we have very high rates of certain cancers. Major culprits appear to be refined carbohydrates and lack of exercise.
In the late 1940s, Ancel Keys noted the increasing heart attack rate in North America and blamed dietary saturated fats and cholesterol in animal products. John Yudkin in England blamed sugar. At that time, Ancel Keys won the debate and Fred Staire, the chairman of Nutrition at Harvard School of Public Health and a personal friend of mine, wrote that sugar is safe. John Yudkin died discredited in 1997, but today it appears that he was a prophet.
Due to the acceptance of Ancel Keys' views, scientists developed drugs to lower cholesterol and told people to avoid saturated fats. The rate of heart attacks has gone down, primarily because of drugs and a better understanding of what causes them. Yet the incidence of diabetes and obesity keep rising. The culprits appear to be refined carbohydrates, particularly all sugars.
High blood sugar damages every cell in your body. After a person eats refined carbohydrates, particularly any sugared drinks, blood sugar can rise too high. This causes sugar to stick to the outside surface of cell membranes where it is converted by a succession of chemical reactions to sorbitol which destroy the cell to damage every cell in your body to cause blindness, deafness, heart attacks, strokes and all the side effects of diabetes.
Being fat causes high blood sugar levels. Before insulin can do its job of driving sugar into cells, it must first attach on special hooks on cells called insulin receptors. Fat inside cells blocks insulin receptors. Muscle cells full of fat cannot respond to insulin and the sugar remains in the bloodstream. Full fat cells send out hormones that block insulin receptors to prevent insulin from clearing sugar from the bloodstream.
High rises in blood sugar make you fat and cause diabetes.
When blood sugar levels rise too high, the pancreas releases large amounts of insulin. Insulin converts sugar to triglycerides. If you do not burn these triglycerides for energy, they fill fat cells with fat and you gain weight. Full fat cells block insulin receptors so blood sugar rises and you become diabetic.
Exercise helps to prevent diabetes.
Sugar cannot enter resting muscles unless insulin is there to drive the sugar into muscles. However actively contacting muscles can draw sugar from the bloodstream without needing insulin. So during exercise, muscles can remove sugar from the bloodstream to prevent the extra sugar from damaging cells and being converted to fat. It also helps make insulin receptors on cells respond to insulin and push sugar into cells.
You need to exercise every day.
Muscles draw sugar from the bloodstream without insulin only when they are actively contracting or lack oxygen and they can continue drawing sugar without insulin maximally for up to an hour after you finish exercising. They lose all ability to remove sugar without insulin 17 hours after you finish exercising. Since the sugar-lowering benefit of exercise lasts in muscles no more than 17 hours, you must exercise every day to retain this benefit.
The highest rises in blood sugar come from sugar in drinks.
All sugared drinks cause very high rises in blood sugar levels. Orange juice will cause the same high rise in blood sugar as sugared soft drinks. When food enters your stomach, the pyloric sphincter at the end of the stomach closes. Then solid food is converted to a liquid soup that is pumped into the intestines by stomach muscle contractions. An orange can stay in your stomach up to five hours, while orange juice passes immediately into your intestines where it is absorbed, causing a rapid rise in blood sugar.
Foods made from flour also cause high rises in blood sugar.
Grains are seeds of grasses. They have a thick capsule that is so tough that you have to cook them for at least an hour just to make them palatable. Blood sugar barely rises after you eat WHOLE grains. However when you grind whole grains into a powder, the flour that is formed can enter the bloodstream immediately to cause a high rise in blood sugar. So pastas and breads can cause high rises in blood sugar, even if they are made from whole grains.
Diabetics should eat fruits and whole grains, and so should you.
Fruits are full of sugar. However, diabetics who do not eat fruits do very poorly. Everyone should eat fruits and whole grains, even those who are overweight, diabetic, or have high cholesterol levels. Everyone should restrict sugared drinks and flour, particularly if they are overweight, diabetic or have heart problems.
Where does meat fit into this picture?
The saturated fat in red meat has been shown to block insulin receptors and raise blood sugar levels. The monounsaturated fats in fruits, whole grains and vegetables have been shown to unblock insulin receptor.
What's the best way to lower high cholesterol?
The best way to lower cholesterol is to restrict calories. It is far more effective than restricting dietary fat and dietary cholesterol. If you ate nothing but fatty meat and reduced your calories by a third, your cholesterol would drop significantly. The cholesterol that you eat in meat, fish and chicken goes to your liver where it is broken down into 2-carbon units. If you do not have enough calories, these 2-carbon units are burned for energy. On the other hand, if you have lots of extra calories, the 2-carbon units are converted to cholesterol to raise your blood cholesterol level.
What is a healthful diet?
You can eat all the fruits, vegetables, whole grains, beans, seeds and nuts you want. You should restrict all refined carbohydrates made from flour and avoid sugared drinks, except when you are exercising. I believe that you should also avoid red meat; AND you should exercise every day.