Melbourne Holistic Health Group

Published in Articles - Women's Health & Fertility on 30 November 2011 by Melbourne Holistic Health Group

Insulin resistance is recognised as a significant underlying factor in PCOS. While not all women with PCOS have insulin resistance, most women (estimates vary from 50-80%) have some degree of insulin resistance and this will impact on the degree and severity of symptoms women with PCOS experience. Insulin resistance also increases risk of other diseases such as cardiovascular disease and metabolic syndrome.

What is insulin resistance?

Insulin is a hormone in the body which functions primarily to regulate blood sugar levels. When blood sugar levels rise (typically after eating a meal) the body’s response is to secrete insulin from the pancreas. Insulin acts to transport glucose (the form of sugar in the blood) from the blood stream and into cells by binding to insulin receptors. Glucose is then used by the cell as an energy source for a myriad of metabolic functions. With insulin resistance this process has become dysfunctional. The insulin receptors which allow insulin to transport glucose into the cell have become less sensitive to the effects of insulin (by either an inactivation of receptors or a decrease in receptor concentration), which results in increased sugar levels in the blood, rather than being transported in the cells where it is needed.

What causes insulin resistance?

The causes of insulin resistance appear to be complex and multi-factorial. At a cellular level, there are a number of factors which affect the way an insulin receptor functions. Genetic factors such as a family history of type 2 diabetes may predispose an individual to insulin resistance. We now know that one of the major triggers of insulin resistance is obesity, and particularly abdominal obesity. However insulin resistance does not only occur with obesity. Rates of insulin resistance in normal-weight PCOS women, is actually comparable to rates of insulin resistance in overweight women with PCOS. Other lifestyle factors such as being inactive or sedentary, having a poor diet, smoking, ageing and certain pharmaceutical drugs can aggravate insulin resistance.

What role does insulin resistance play in PCOS?

In a picture of insulin resistance, blood levels of insulin rise as the body attempts to maintain normal glucose levels. Elevated blood insulin affects reproductive hormones and in particular levels of androgens. It is understood that elevated insulin levels increase the production of androgens by the ovary, and may indirectly increase adrenal androgen production. Symptoms associated with elevated androgens or ‘hyperandrogenism’ include acne and male-pattern hair growth or hair loss. Insulin resistance also contributes to the failure to ovulate and associated infertility.

What can be done about insulin resistance in PCOS?

While medical management of PCOS may involve insulin-sensitising drugs such as metformin (Diabex, Glucophage), lifestyle and dietary changes are considered the primary focus of intervention. For many women with PCOS, diet and lifestyle changes may be all that is required. For overweight women a modest reduction in body weight (5-10%) dramatically reduces insulin resistance and improves a number of metabolic and reproductive features of PCOS. A low GI diet is more effective than exercise alone in achieving weight loss. However, exercise not only enhances weight loss, but has been shown to independently improve insulin sensitivity and improve cycle regularity, and so is important for all women with PCOS regardless of body weight. Overall calorie reduction, and reducing portion sizes are also important components of weight loss.

What is a low glycaemic index (GI) diet, and how can it help?

The glycaemic index is a measure of the effects that different carbohydrate-rich foods have on blood sugar levels. High-GI foods are those which break down quickly during digestion and result in rapid increases in blood glucose levels. Examples of high-GI foods include pure glucose (such as lollies), fruit juice, white bread and rice bubbles. Low-GI foods on the other hand, break down more slowly so that glucose is steadily released into the bloodstream and blood sugar levels are correspondingly more stable. Examples of low GI foods include chickpeas, untoasted muesli and whole apples with skin on. Factors which influence the GI of foods include the fat, protein and fibre content of the food, as well as how the food is prepared or cooked. A low-GI diet has been shown to improve insulin resistance and was originally developed to help people with diabetes. Following a low-GI diet is now accepted as beneficial not only for diabetics, but as a healthy eating guide for everyone. Our naturopaths can go through with you in detail aspects of a low-GI diet including food choices, cooking methods and meal ideas.

What can your naturopath do for you?

As part of a naturopathic consultation, our naturopaths can help you address key factors driving the picture of insulin resistance in PCOS. By improving insulin sensitivity, the reproductive and metabolic features symptoms of PCOS (such as infertility, menstrual cycle irregularity, male pattern hair growth and acne) are likely to improve. Reducing insulin resistance will also help reduce the risk of other diseases such as cardiovascular disease and type-2 diabetes. While there are a number of herbs and nutritional supplements which can support healthy blood sugar levels, achieving and maintaining an ideal weight, as well as developing an exercise program and adopting a low-GI diet are the key features of treatment and our naturopaths can specifically tailor a program to help to achieve this.

Related articles:

• What is Polycystic Ovary Syndrome (PCOS)? 
• Improving PCOS Symptoms Through Exercise and Weight Loss 
• PCOS and Pregnancy
• Infertility Treatments at MHHG