Cochin Cardiac Club

Health Blog by Dr.Uday Nair

INSULIN RESISTANCE (IR)



Insulin resistance(IR)is not a disease as such but rather a state or condition in which a person's body tissues have a lowered level of response to insulin, a hormone secreted by the pancreas that helps to regulate the level of glucose (sugar) in the body. Normally, food is absorbed into the bloodstream in the form of sugars such as glucose and fats and other basic substances. The increase in glucose in the bloodstream signals the pancreas to increase the secretion of  insulin. This hormone attaches to cells, removing glucose from the bloodstream so that it can be used for energy.In insulin resistance, the body's cells have a diminished ability to respond to the action of the insulin hormone. To compensate for the resistance, the pancreas secretes more insulin.


What is Metabolic Syndrome or Insulin resistance syndrome(IRS)?



Many people with insulin resistance and high blood glucose have other conditions that increase the risk of developing type 2 diabetes and damage to the heart and blood vessels, also called cardiovascular disease. These conditions include having excess weight around the waist, high blood pressure, and abnormal levels of cholesterol and triglycerides in the blood. Having several of these problems is called metabolic syndrome or insulin resistance syndrome, formerly called syndrome X.


Insulin Resistance Syndrome is a combination of problems.  It is diagnosed when a patient has at least three factors identified as part of IRS.


A diagnosis of Insulin Resistance Syndrome (IRS) may be made when any three of the following criteria are met:


    Fasting Glucose of > 112 mg/dL,or current use of diabetic medication

    Abdominal obesity (especially apple shaped body) with a waist circumference:
           Women   >35 inches
           Men     >40 inches

    High Blood Pressure:
        Systolic    > 130 mm HG or 
        Diastolic   > 85 mm HG or
        current use of blood pressure medication

    Low HDL Cholesterol ("good" cholesterol)
          Women    < 50
          Men      < 40, or

    Elevated Triglycerides
          >150 mg/dL

How does insulin work in our body?

After a person eats a meal, digestive juices in the small intestine break down starch or complex sugars in the food into glucose, a simple sugar. The glucose then passes into the bloodstream. When the concentration of glucose in the blood reaches a certain point, the pancreas is stimulated to release insulin into the blood. As the insulin reaches cells in muscle and fatty (adipose) tissues, it attaches itself to molecules called insulin receptors on the surface of the cells. The activation of the insulin receptors sets in motion a series of complex biochemical signals within the cells that allow the cells to take in the glucose and convert it to energy. If the pancreas fails to produce enough insulin or the insulin receptors do not function properly, the cells cannot take in the glucose and the level of glucose in the blood remains high.
The insulin may fail to bind to the insulin receptors for any of several reasons. Some persons inherit a gene mutation that leads to the production of a defective form of insulin that cannot bind normally to the insulin receptor. Others may have one of two types of abnormalities in the insulin receptors themselves. In type A, the insulin receptor is missing from the cell surface or does not function properly. In type B, the person's immune system produces autoantibodies to the insulin receptor.
In the early stages of insulin resistance, the pancreas steps up its production of insulin in order to control the increased levels of glucose in the blood. As a result, it is not unusual for patients to have high blood sugar levels and high blood insulin levels (a condition known as hyperinsulinemia) at the same time. If insulin resistance is not detected and treated, however, the islets of Langerhans (the insulin-secreting groups of cells) in the pancreas may eventually shut down and decrease in number.


What causes insulin resistance(IR)?



Genetics plays a big part.Some people are actually born insulin resistant. Lack of physical activity causes the cells to be less responsive to insulin. Most experts agree that obesity leads to more insulin resistance. However, it almost certainly also works the other way around: Insulin resistance promotes weight gain. So a vicious cycle can be set up with insulin resistance promoting weight gain, which promotes more insulin resistance.

What are the Symptoms of IR?



  • Fatigue.
  • Brain fogginess and lack of ability to concentrate.
  • High bloodstream sugar.
  • Intestinal bloatedness – most intestinal gas is created from carbohydrates within the diet, mostly individuals that humans cannot digest and absorb.
  • Drowsiness, especially after foods.
  • Putting on weight, body fat storage, difficulty slimming down – for most of us, excess fat comes from high body fat storage the body fat in insulin resistance is usually saved around abdominal organs both in males and women. It’s presently suspected that hormone production for the reason that body fat really are a stressful reason for blood insulin resistance.
  • Elevated bloodstream triglyceride levels.
  • Elevated bloodstream pressure. Lots of people with hypertension are generally diabetic or pre-diabetic and also have elevated blood insulin levels because of blood insulin resistance. Among insulin’s effects would be to control arterial wall tension through the body.
  • Depression. Because of the deranged metabolic process caused by blood insulin resistance, mental effects, including depression, aren’t uncommon.
  • Elevated hunger.
  • Acanthosis nigricans (Hyper pigmentation of the skin)

What are the Conditions Associated with IR? 



Insulin resistance is commonly associated with diabetes and cholesterol abnormalities. The other ailments linked to the condition include:
  • Cirrhosis of the liver
  • Arteriosclerosis
  • Coronary artery disease
  • Peripheral vascular disease
  • Skin lesions, such as those that manifest in the onslaught of acanthosis nigricans and axilla
  • Reproductive abnormalities, especially in the case of women
  • Hyperandrogenism
  • Growth abnormalities

How is IR Diagnosed?


  • A physician can identify individuals who are likely to have insulin resistance with a detailed patient history, physical examination, and laboratory testing.Glucose levels in conjunction with fasting insulin levels provide the physician with information as to whether insulin resistance is present, or not present, in patients without diabetes. A firm diagnosis cannot be made simply based on this, since the lab techniques for measuring insulin can vary, and there is no absolute value used for the definition. However, an insulin level above the upper quartile in the fasting state in someone without diabetes is considered abnormal. In addition, an oral glucose tolerance test (OGTT) can be used to detect insulin resistance and is more sensitive for detecting milder/earlier disease. It involves drinking a known amount of simple sugar and measuring blood glucose and insulin levels at baseline as well as one and two (and sometimes three) hours after drinking.

Can IR contolled or prevented?


Losing weight can help to decrease the extent of insulin resistance.
Changing your diet can also help to halt the progression of or decrease the effect of insulin resistance.



What are the steps to keep in mind?



  • Lose seven percent of your body weight to reduce the risk of your insulin resistance progressing to diabetes by 60 percent.
  • Plan three meals and two snacks a day within your target daily calorie count. To optimize nutrition and reduce the level of glucose your body has to contend with at one time, select foods which include fresh vegetables and whole fruits; whole grains; and omega-3 fatty acids such as olive oil, avocado, salmon and walnuts while eliminating white flour, sugar and saturated dietary fat. This eating style can result in a significant correction of of both blood insulin and blood glucose levels.
  • Walk 30 minutes per day at least five days per week to decrease insulin resistance and circulating insulin levels.For a greater degree of fat loss, especially in the abdomen, increase the intensity of the walk periodically.Walking in locations with an incline, taking longer strides or walking faster can achieve better results.
  • Cigarette smoking, in most, though not all, studies, as well as exposure to secondhand smoke and use of nicotine replacement products, have been associated with insulin resistance. While smoking cessation has been shown to increase insulin sensitivity in healthy people, no research has investigated the effect of quitting smoking on people with IRS.
  • Alcohol consumption in the light to moderate range is associated with better insulin sensitivity in healthy, nondiabetic people. Since alcohol consumption also reduces other risk factors for heart disease, it does not appear that people with IRS would benefit from avoiding alcohol if they are currently light to moderate drinkers. However, alcohol is potentially addicting and can increase the risk of other diseases, so people with IRS who are not users of alcohol should consult a doctor before starting regular consumption of alcoholic beverages.