Insulin resistance, or metabolic syndrome, is an increasingly common problem where cells become less responsive to the insulin your pancreas produces. Insulin resistance affects between 60 and 70 million Americans, many of whom are unaware they have it. Insulin is a hormone that “unlocks” cells so that glucose can enter after a meal. People who are insulin resistant have larger amounts of insulin circulating in their bloodstream. When cells are exposed to more insulin, they become less sensitive to its effects and fail to “unlock” to allow glucose to enter.
What happens then? Since glucose remains in the bloodstream, more insulin is pumped out in a futile attempt to get it into cells. Over time, the pancreas can “burn out” and be unable to meet the demand for higher insulin production. That’s when type 2 diabetes sets in. Plus, insulin resistance increases the risk of other health problems like heart disease. Needless to say, you want to avoid the problem of insulin resistance – but how do you know if you have it?
Signs and Symptoms of Insulin Resistance
Unlike some health problems, early insulin resistance doesn’t always cause symptoms and the symptoms people have are usually vague. When adequate glucose isn’t entering cells due to insulin resistance, you may have vague symptoms like brain fog, lack of energy, constant hunger, difficulty focusing and feel tired and sleepy after a meal. These symptoms are non-specific and can be due to a number of problems including a poor diet and lack of sleep.
Some people who are insulin resistant have a skin condition called acanthosis nigricans. This condition is characterized by skin darkening and thickening, usually under the arms or in areas where there are skin folds. Women may have fertility problems or irregular periods and have increased hair growth on their body.
Even though the symptoms of insulin resistance are usually vague, certain signs are suggestive of it. Even though people who are insulin resistant are often overweight, this isn’t always the case. Twenty-percent of people with this problem are of normal weight, so don’t assume you can’t be insulin resistant if you’re slim. Doctors can make the diagnosis of insulin resistance based on certain criteria. If a person has three of the five, they meet the criteria for insulin resistance. These criteria include:
Waist size 35 inches or greater in a woman and 40 or more inches in a man.
Blood pressure of 130/85 mm. Hg. or greater
HDL-cholesterol level of less than 50 mg/dl in women or less than 40 mg/dl in men. Your doctor can check this through a blood test.
Fasting triglycerides of 150 mg/dl or greater. Again, this can be checked through a blood test.
Fasting blood sugar level of 100 mg/dl or greater.
If you have three of these signs, you meet the criteria for insulin resistance regardless of your weight. This puts you at five times greater risk for type 2 diabetes and places you at a higher risk for heart disease. That’s why it’s important to “know your numbers” including your blood pressure, blood sugar, triglyceride level, and LDL and HDL-cholesterol levels as well as your waist size.
Reducing Your Risk for Insulin Resistance
The best way to prevent and treat insulin resistance or metabolic syndrome is to lose weight if you’re overweight, and exercise. The composition of your diet is important too. Processed carbohydrates that are low in fiber stimulate more insulin release and worsen the problem – so can eating white potatoes and white rice.
The best diet to treat insulin resistance is one that emphasizes lean protein sources, especially fish, fiber-rich carbs from vegetables and moderate amounts of healthy fats like the monounsaturated fats in nuts and olive oil and omega-3s in fatty fish. It’s also important to eat magnesium-rich foods like seafood, nuts, and lentils since low magnesium levels may worsen insulin resistance.
Exercise not only helps insulin-resistant people lose weight, but it also increases the sensitivity of cells to insulin. A combination of strength training and high-intensity interval cardio exercises is ideal for improving insulin sensitivity and reducing abdominal fat.
Don’t underestimate the importance of sleep. Skimping on sleep reduces insulin sensitivity and makes it harder to control your weight. Seven to eight hours is the amount most people need for optimal insulin sensitivity and health.
The Bottom Line?
Metabolic syndrome, or insulin resistance, doesn’t always give you obvious symptoms and you don’t have to be overweight to have it. Get your numbers checked by visiting your doctor once or twice a year, depending upon your age and risk factors, and stick to a healthy diet and an exercise plan to reduce your risk for future health problems.
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