Until 30 year ago, most doctors felt that insulin was a good hormone and the more you have, the healthier you are. Then Gerald Reaven of Stanford showed that people with high insulin levels are at high risk for heart attacks because insulin constricts arteries to block those leading to the heart. Further research showed that insulin also is a fat hormone because it affects your hypothalamus in your brain to make you hungry, your liver to make more fat, and the fat cells in your belly to take up the fat, which makes YOU fatter.

Then in 1978, research showed that certain foods raise insulin more than others and foods can be classified by how high they raise blood sugar levels in comparison to eating pure refined sugar. When you eat, your blood sugar level rises and the higher blood sugar levels rise, the more insulin your pancreas releases to help lower sugar levels. So, what you eat is very important because foods that raise blood sugar levels the most are the ones most likely to raise blood insulin levels and increase your risk for a heart attack.

Carbohydrates are chains of sugar molecules lined in a row. They are found in all plants and foods made from plants such a bakery products and pastas. Carbohydrates can be a single sugar, two sugars bound together, three or four sugars. Thousands of sugars bound together are called starch, and millions of sugars bound together so tightly that you cannot break them down are called fiber. Only single sugars can pass from your intestines into your blood stream.

When you eat food that contains starch, your intestines release enzymes that knock off the end sugar and it is absorbed immediately. You continually knock off end sugars rapidly and they are absorbed almost immediately. All simple sugars and starches that are broken down rapidly go into the bloodstream rapidly to cause a high rise in blood sugar. Resistant starches contain long chains of sugars that cannot release their end sugars, so they can't be absorbed and pass to the intestines where they are broken down to be converted into fatty acids that help prevent colon cancer and heart attacks.

That's why you want to eat carbohydrates that release their sugars slowly and restrict carbohydrates that release sugars rapidly. The easier it is to break carbohydrates down into single sugars, the higher your blood sugar level rises and the more insulin you produce, which constricts arteries and increases your risk for a heart attack.

The most healthful carbohydrates are those left with fiber where nature puts it in seeds, nuts, beans, whole grains and vegetables. The most dangerous carbohydrates for diabetics and people who are trying to lose weight are foods made from flour, white rice or milled corn; or with added sugars.

The best carbohydrates are those that have a tight capsule that releases carbohydrates slowly such as whole grains such as wheat berries, rye berries, oat groats, quinoa, spelt, buckwheat and so forth; vegetables, beans, seeds and nuts.

Root vegetables contain stored sugar and cause a high rise in blood sugar levels, but they contain so many healthful nutrients that you need them to be healthy. So potatoes, carrots and beets can be eaten safely with other foods to slow absorption. For example, eating a potato with a piece of fish slows absorption of the sugars. The same applies to fruits. When you eat fruit in a vegetable salad, the sugar is absorbed slowly. When you eat the fruit alone, blood sugar levels rise quickly.

The most healthful way to eat is to leave nature alone. Eat carbohydrates the way nature packages them without first grinding them into very small pieces or squeezing them into juices that remove their fiber.

Dr. Gabe Mirkin has been a radio talk show host for 25 years and practicing physician for more than 40 years; he is board certified in four specialties, including sports medicine. Read or listen to hundreds of his fitness and health reports at http://www.DrMirkin.com

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