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Insulin Resistance: Risk Factor for Heart Disease and Diabetes

Insulin resistance is a metabolic disorder that occurs when the body's cells cannot properly intake insulin. Insulin, which is produced in the pancreas, is a hormone that helps the body form energy from blood glucose, or blood sugar from digested food, according to the National Institute of Diabetes and Digestive and Kidney Diseases.

Insulin resistance is a risk factor for developing heart disease and type 2 diabetes, the most common form of diabetes. More than 50 million Americans have metabolic disorders that include insulin resistance, according to the American Heart Association. The condition occurs in more than 50 percent of obese children, according to a 2006 study published in the journal Diabetes Care.

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Causes & Symptoms

Insulin resistance is directly caused by the body's muscle and fat tissues to respond to the effects of insulin, which is secreted after eating to transport glucose into cells, according to the American Association for Clinical Chemistry

The likelihood of developing insulin resistance can be traced to certain genes, but being overweight and not exercising are big contributors, according to the National Institute of Diabetes and Digestive and Kidney Diseases.

A recent study published in May 2010 in the Journal of Clinical Endocrinology & Metabolism also showed that a night of short sleep can also increase insulin resistance.

There are not usually any symptoms of insulin resistance because ''the body is able to keep pace with the need for extra insulin production for many years,'' the American Association for Clinical Chemistry said. However, the body cannot keep up forever and pre-diabetes – or higher-than-normal glucose levels in the blood – results, which can in turn lead to diabetes.

Diagnosis & Tests

Doctors don’t usually test or diagnose for insulin resistance because the most accurate measure, the euglycemic clamp, is an expensive tool that is usually used only in research. However, they can test for pre-diabetes by doing a blood test, according to the National Institutes of Health. Also, insulin resistance is one of the present conditions in metabolic syndrome, which is a condition that could also include a waist measurement of 40 or more inches in men and 35 or more inches in women, high triglyceride levels, low ''good'' cholesterol levels and high blood pressure.

It’s also possible to test for pre-diabetes and diabetes by doing a fasting glucose test, which measures glucose levels in people who haven't eaten in eight hours, or a glucose tolerance test, which measures glucose levels in people who haven't eaten in eight hours and then drink a special sweet drink two hours later, according to the National Institutes of Health.

Doctors advise that people should be tested who have risk factors that include: being over the age of 45, overweight or obese, being physically inactive, having a family history of diabetes, having high blood pressure, having low levels of good cholesterol, having a history of cardiovascular disease or having gestational diabetes (during pregnancy).

Treatments & Medications

The only drug that is FDA-approved and recommended for any sort of use in diabetes prevention is metformin, according to the National Institutes of Health. However, the drug is only meant to treat high-risk people younger than 60 with pre-diabetes and a certain body mass index.

However, the American Diabetes Association recommends regular physical activity and eating the right amount of nutritious foods to lose weight and reverse or stall insulin resistance and pre-diabetes. ''You don’t have to lose a lot (of weight); even a loss of 10 pounds can help,'' the association said.

Healthy Eating Tips

The American Diabetes Association offers nutritional guidance for staving off insulin resistance and pre-diabetes. It recommends cutting back on the usual size of meals and going for the smaller portions, drinking calorie-free drinks, eating low-fat versions of regular foods, eating baked or grilled foods instead of fried, eating more vegetables and asking for salad dressing on the side, cutting back on high-fat toppings and opting instead of low-fat dressings, and only keeping low-calorie foods in the house.

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