Many women with PCOS are overweight. They are also insulin resistant. PCOS symptoms, excess weight, and insulin resistance interact with one another, making it hard to tell which one is primarily responsible for a particular symptom. In addition, a genetic predisposition for insulin resistance or PCOS may be involved. For example, a woman with an inherited predisposition to insulin resistance may develop it if she becomes overweight and then develops PCOS. Another woman with an inherited predisposition to PCOS may develop it on becoming overweight and insulin resistant.
What we do know for sure is that the great majority of American women with PCOS are overweight and insulin resistant, and they can relieve their PCOS symptoms by losing weight. Put very simply, this is how it works:
Weight loss → Reduced insulin resistance → Lowered insulin blood level → Lessened secretion of male hormones by ovaries
The bottom line is that losing 7 to 10 percent of your body weight through healthful eating—and keeping those ten to twenty pounds off through moderate exercise—can effectively reduce your PCOS symptoms. You can do it.
If you have a weight problem and find it extremely hard to lose any of those extra pounds, you may be insulin resistant. When your organs and tissues lose their sensitivity to insulin, a normal amount of insulin is no longer sufficient to process the blood sugar your cells burn as fuel. In response, cells in your pancreas secrete greater amounts of insulin. As your insulin level rises, your PCOS symptoms worsen. This interaction of excess weight, insulin resistance, and PCOS symptoms is complex and varies from woman to woman.
As a general rule, the heavier a woman is, the more insulin resistant she becomes and the more she suffers from her PCOS symptoms. A high insulin level stimulates your ovaries to secrete more male hormones, and they in turn intensify your PCOS symptoms.
In addition to exacerbating PCOS symptoms by increasing insulin levels, excess weight is associated with two major health problems that affect many women with PCOS, namely, type 2 diabetes and cardiovascular disease. About 70 percent of the Americans who develop type 2 diabetes do so because of increased body weight. In addition, when a person develops type 2 diabetes, excess weight interferes with management and recovery. In the Diabetes Prevention Program study, a 5 to 7 percent weight loss in the first year, with about three hours of brisk walking per week, lessened the development of type 2 diabetes by nearly 60 percent over four years.
Besides slowing the progress of PCOS and diabetes, weight loss has perhaps more familiar cardiovascular benefits, particularly in lowering blood pressure and blood lipid levels and in reducing arterial inflammation. Only in recent years has it been fully realized that high blood pressure, high blood lipid levels, type 2 diabetes, PCOS, and excess weight can interact among themselves to raise a woman’s risk of heart disease and stroke. In chapter 3 we will look at some of the ways in which this can happen in the insulin resistance syndrome. Having insulin resistance does not mean that you have the insulin resistance syndrome. As its name implies, the insulin resistance syndrome is a collection of symptoms that interact with one another as health risk factors.
Margaret, a marketing executive for a big electronics firm, sought medical help when she found herself becoming sluggish and gaining weight. Because she had previously been so attractive and lively, people immediately noticed the change in her. Her high triglyceride and low HDL levels caused her family doctor to suspect that she might be insulin resistant, although the result of her fasting glucose test was normal.
Margaret tried to lead a healthier life, but her job required lots of desk work and socializing outside the office. She continued to gain weight and feel sluggish. Then, to her horror, she noticed that her hair was getting thinner. She could hardly count the number of hairs that fell out every time she shampooed, there were so many of them! A dermatologist told her that this trait probably ran in her family and that frequent shampooing would not make the hair loss worse.
Then she saw an endocrinologist. He diagnosed her as having a hypothyroid condition, and Margaret took the drugs he prescribed. When they made little or no difference, Margaret grew frustrated. If she was insulin resistant … if her genes were bad … if she had an underactive thyroid … she could accept all that, so long as she could do something to correct the situation. But so far, nothing her doctors gave her made her feel any better.
She searched around for other medical opinions. What she heard was more bad news. Lab tests now showed that she had impaired glucose tolerance—whatever that meant! She was surprised to learn that insulin resistance is the metabolic disorder basically responsible for type 2 diabetes and that impaired glucose tolerance is a stepping-stone along the way to full-blown diabetes. She also learned that these health problems can be associated with the cluster of other abnormalities known as the insulin resistance syndrome.
One of her physicians discussed her case with me at a medical conference, and I suspected that PCOS might underlie all her troubles. When Margaret came to see me, I found that her male hormone blood levels were much higher than normal, and a pelvic ultrasound revealed that she had typically enlarged polycystic ovaries. Further tests revealed that she had PCOS. When Margaret lost weight and became less sedentary she started to feel better almost immediately. People started to remark on how well she looked. The medications I prescribed prevented further hair loss and helped control some markers of cardiovascular risk.
I explained to Margaret that she was not cured, that she would always have PCOS and would always need to keep its symptoms under control. Keeping her weight at a healthy level lowered both her insulin and male hormone levels, as well as reduced her impaired glucose tolerance. In her case, this was enough to keep her free of symptoms and restore her to her lively, attractive self.
Physicians find insulin resistance difficult to diagnose, because it cannot be reliably detected by any convenient test administered in a doctor’s office. Although insulin resistance and a high insulin blood level (hyperinsulinemia) usually occur together, doctors often discuss hyperinsulinemia as if it were a separate condition. This is because more symptoms can be traced directly to it than to insulin resistance, and therefore it can be talked about with more certainty.
Many cases of insulin resistance are believed to be genetic, and others may be due to obesity, physical inactivity, aging, stress, drugs (cortisone, thiazide diuretics), pregnancy, and diseases (Cushing’s syndrome, growth hormone excess). Being obese triples your risk for insulin resistance, although some obese people are not insulin resistant. Although excess central or visceral fat is typical of people with insulin resistance, many people with an all-over distribution of excess fat are also insulin resistant.
Are you overweight because you are insulin resistant? Or are you insulin resistant because you are overweight? Which came first? The answers may vary from person to person, and each condition affects the other. Discovering which came first is of much lesser importance than finding an effective therapy. You can most certainly do something about being overweight (see chapters 6 and 7).
Eating certain carbohydrate-rich foods significantly boosts your blood sugar level, and any rise in blood sugar is answered by an increased secretion of insulin. Insulin helps your blood sugar enter cells, where it’s consumed for energy. Cells store some excess blood sugar for short-term use, and put some in long-term storage as triglycerides in fat cells. People of normal weight don’t take in much more food than they can consume as fuel in the form of blood sugar. In other words, they don’t ingest many more calories than they can burn.
At some point in their lives, many people begin to notice that they don’t burn off extra calories the way they used to. For example, they can’t lose weight as easily as they once could. The straightforward balance of calories in and calories burned in a healthy body doesn’t seem to apply to their bodies anymore. Often the cause of this is the development of insulin resistance.
With insulin resistance, your body cells become less sensitive to insulin and require more of it to process blood sugar. When this happens, your body detects the presence of unprocessed blood sugar and signals the beta cells of your pancreas to secrete more insulin. Then the larger amount of insulin that builds up processes your blood sugar and its level quickly drops.
A rapid drop in the blood sugar level causes you to feel hungry again and crave sweets and carbohydrate-rich snacks or fruits. You may also have other symptoms of low blood sugar (hypoglycemia), such as light-headedness, sweats, tremors, drowsiness, irritability, or palpitations. When you eat more carbohydrate rich foods, your blood sugar level rises again. In response to this, more insulin is secreted. You can see where this is going: You’re suddenly caught up in unending cycles.
During each cycle, the insulin is depositing some of your excess blood sugar in the form of triglycerides in fat cells. The weight accumulates quickly. The more weight you put on, the more severe your insulin resistance becomes. The more severe your insulin resistance becomes, the more weight you put on. Perhaps through overstimulation, the insulin-secreting cells of the pancreas work progressively less well during prolonged insulin resistance and may become exhausted, leading to clinical type 2 diabetes.
Here are ten warning signs that you could be insulin resistant. You’ll recognize many of these indications from the list of PCOS symptoms in chapter 1, a crossover that illustrates the close relationship between the two conditions.
1. You are middle-aged or older and overweight.
2. You carry most of your excess fat in your midsection, with a waist measurement of 35 inches (88 centimeters) or more.
3. You have acanthosis nigricans (dark skin patches).
4. You have skin tags.
5. You have symptoms of hypoglycemia (such as light-headedness or drowsiness) half an hour to three hours after eating.
6. You have recently gained weight and seem unable to lose it.
7. Your periods are irregular.
8. You have a close family member with PCOS.
9. You have high blood pressure or blood lipid abnormalities.
10. Other close family members have the same symptoms or signs.
Although none of these warning signs is a definite indication of insulin resistance, the more of them that apply to you, the more reason you have to suspect that you could be insulin resistant.
Discovering whether you are insulin resistant may not be easy. The most reliable way to do so is by the hyperinsulinemic-euglycemic clamp technique. This is a complex lab procedure involving infusions of insulin and glucose, and lasting one to three hours. It is used mostly at research centers for special studies.
Regular lab tests performed on blood samples are not as reliable for detecting insulin resistance as they can be for other conditions. Tests based only on a measurement of fasting glucose or insulin levels may be inaccurate, particularly when a woman’s basal insulin level is in the normal or high normal range or when her weight is normal. In fact, the presence or absence of insulin resistance is considered to be most difficult to assess in non-obese women with PCOS.
But even if their reliability is often questionable, lab tests— that’s tests, plural—are worth taking. It’s best not to rely on one test alone. If the results of several different types of tests all point to the same conclusion, you can have more confidence in the verdict.
You will recognize these tests are among those described previously as important for diagnosing PCOS, once more showing the importance of assessing insulin resistance in women with PCOS.
Before taking any of these tests, show your doctor the results of any lab tests you have had in earlier health checkups. Was your triglyceride level high, and your HDL cholesterol level low? This combination of lipid abnormalities is often an indication of an insulin resistance problem.
Although these are separate lab tests, they can all be done from a single blood sample taken in your doctor’s office. Therefore, as far as you are concerned, the number of tests performed does not affect you so long as they are covered by your medical insurance, as they most likely will be.
Fasting insulin. Your insulin level can vary from test to test after ten to twelve hours of fasting, but repeated levels of 13 uIU/mL or above indicate a probability of insulin resistance.
Fasting glucose/insulin ratio. This test is based on the ratio between the results of two other lab tests, fasting glucose and fasting insulin. A ratio of less than 4:5 suggests insulin resistance.
2-Hour glucose tolerance test. This test can show that you have impaired glucose tolerance (an intermediate step between insulin resistance and type 2 diabetes, to be discussed in chapter 4), even when your blood glucose level is normal. Two hours after ingesting 75 grams of glucose, a blood glucose level of 140 to 199 mg/dL indicates impaired glucose tolerance. The two-hour insulin levels of people with such results often exceed 80 uIU/mL, signaling increased pancreatic secretion of insulin in response to high blood sugar. During and after this test, such high insulin levels are liable to cause hypoglycemic symptoms. They can be quickly relieved by eating a high-sugar food.
Sex hormone binding globulin (SHBG) test. The SHBG level correlates well with insulin resistance. In women with PCOS (and in most obese women, even if they do not have PCOS), a low SHBG level indicates that excess insulin has caused the liver to make less SHBG, which signifies the probable presence of insulin resistance and causes a high level of free (or unbound) testosterone. The SHBG level is an indirect but important test in determining the presence or absence of insulin resistance. Taking a birth control pill raises your SHBG level significantly, as do some other treatments. In such cases, SHBG is not useful in the initial evaluation of insulin resistance. It can be used as a marker, however, in noting improved insulin resistance with treatment of PCOS. Exercise and weight reduction also improve your SHBG and HDL levels, indicating a lesser effect of insulin and probable improvement in your insulin resistance.
Insulin resistance may be mild to severe, and its intensity often varies according to body weight. You can’t cure it, but you can keep it under control. Many people inherit the condition and go through life without knowing they have it or experiencing its effects, simply because they don’t become overweight.
Regardless of what diet you choose to follow, losing weight means ingesting fewer calories. You know that your insulin resistance is improving when your waistline is shrinking. In fact, a smaller waistline can be a more reliable indicator of good control than your weight loss.
As you will learn in chapter 6, high-fiber, high-carbohydrate diets composed of low-calorie foods reduce insulin resistance and body weight. Foods with a low glycemic index do this, too, although some nutritionists claim that the benefits have at least as much to do with high fiber content as low sugar content.
You can also keep track of how your insulin resistance is diminishing by keeping an eye on your low density lipoprotein (LDL or “bad”) cholesterol level.
LDL below 100: This is the goal for most people with type 2 diabetes. If you have type 2 diabetes, as many women with PCOS do, your LDL level should be reduced to 80 mg/dL.
LDL 100-129: You have several options. You can increase the intensity of your LDL-lowering therapy and add nicotinic acid and possibly ezetimibe (Zetia) while you intensify control of your fat intake and other risk factors, such as your blood sugar level.
LDL 130 or higher: At this level, most women with PCOS need to combine lifestyle changes with LDL-lowering drugs, usually statins (for example, Lipitor), to reach an LDL below 100 mg/dL.
Another good way to track your progress is to follow your triglyceride and HDL levels, which we’ll discuss in chapter 4.