PCOS is a metabolic disorder that affects 5 – 7.5% of all women. It is the number one cause of infertility and if left untreated, can increase risk of endometrial cancer. In addition, women with PCOS are at a greater risk for heart disease and diabetes. Until recently, diet was not thought of as an important adjunct in treatment. However, since the fairly recent discovery regarding the role insulin resistance plays many experts now believe that diet should be a part of the treatment plan. It is believed that diet can help reduce insulin resistance, which can not only help erratic menses, hirutism and acne, but may decrease the risk of heart disease and diabetes as well.
Role of Insulin in PCOS
Exactly why and how PCOS develops is not quite clear, however most experts now agree that insulin plays a major role. Insulin is a powerful hormone that is released by the body’s pancreas in response to eating food – especially carbohydrates. It transports sugar out of the blood and into muscle, fat and liver cells, where it is converted to energy or stored as fat. Many women with PCOS have insulin resistance. This means that the process of getting the sugar out of the blood and into the cells is defective – the cells are “resistant” to insulin. The pancreas must secrete more and more insulin to get sugar out of the blood and into the cells. High levels of insulin or hyperinsulinemia, can wreak havoc in the body, causing any or all of the following conditions: polycystic ovaries, weight gain and/or difficulty losing weight, increased risk of heart disease by increasing LDL and triglycerides, decreasing HDL and increasing clotting factors. In addition, it can increase risk of diabetes by up to 40% by age 40.
The discovery of insulin’s role in PCOS has brought hopes for better treatment. Treatment is no longer just aimed at treating the individual concerns (i.e.: erratic menses, hirutism, acne, etc.), but instead is now aimed at treating one of the underlying causes – insulin resistance. If insulin resistance is present, it is best treated with diet, exercise and weight loss if needed. Keep in mind that not all women with PCOS have hyperinsulinemia, but the majority do.
Calculating Your Caloric Needs
Since the majority of women with PCOS are overweight, calories are very important. For weight control, remember – all calories, whether from fat, protein or carbohydrate, in excess of your body’s needs, will turn to fat. In order to lose weight, you must stay within your calorie goal.
For weight loss:
- To lose one pound a week, subtract 500 from your maintenance caloric level
- To lose two pounds a week, subtract 1000 calories from the maintenance level
Dietary Recommendations for PCOS
The following recommendations can help you plan your diet. The bottom line is that you need to find a diet that works for you and one that you can live with.
- Do not eat carbohydrates by themselves. Instead, combine them with a protein and / or fat
- Try to select lower glycaemic index foods as they will cause a slower rise in blood sugar. (Glycaemic index is an indicator of how rapidly the food turns to sugar in the blood). The lower glycaemic carbohydrates tend to have more fibre than the higher glycaemic foods. For example, bran cereal (10 gm. fibre/1/2 cup) has a lower glycaemic index than cornflakes (1 gm. fibre/1/2 cup). In other words, select breads, grains and cereals that are as unprocessed as possible.
- Do not take your carbohydrate levels so low that you induce ketosis. You can test for this by purchasing ketone test strips at a pharmacy. Eating less than 40 grams of carbohydrate a day may induce ketosis.
- Space the carbohydrates out during the day. This will cause less of rise in blood sugar and insulin peak as compared to eating all carbohydrates at one meal.
- Avoid those carbohydrates that trigger more hunger or cravings (i.e.. pasta triggers craving for some people).
- Drink at least 8 cups of non-caffeinated fluid as a low carbohydrate intake can cause dehydration.
- For heart health, limit foods high in saturated and trans fats (i.e. fatty red meat, whole milk dairy, butter and stick margarine, chicken skin, fried foods, rich desserts, etc.). Select mainly monounsaturated fats (i.e. olive oil, canola oil, nuts) and omega 3 fats (fatty fish such as salmon and bluefish, flaxseed, nuts) as these fats are heart healthy.
- Exercise on a regular basis.
- Benefits of aerobic exercise:
◦burns calories and aids in weight control
◦lowers blood pressure
◦raises HDL cholesterol
◦may improve insulin resistance (this is proven in type 2 diabetics)
- Benefits of resistance training:
◦builds lean mass which will speed metabolism
◦helps prevent osteoporosis
In conclusion, we know that weight loss is key in decreasing insulin resistance in obese women. It appears that a lower glycaemic diet may play an important role in helping to control insulin levels as well as promoting weight loss.