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PCOS and DIET

By Martha McKittrick, RD, CDE, Registered Dietician, Certified Diabetes Educator, OBGYN.net Editorial Advisor | November 7, 2011

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. Although further research is needed, it is believed that diet can help reduce insulin resistance, which can not only help erratic menses, hirsutism and acne, but may decrease the risk of heart disease and diabetes as well. This article will discuss the role of diet in PCOS and give practical suggestions for meal planning.

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 (ie: erratic menses, hirsutism, 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. Insulin sensitizing medications may be used as well. Most physicians prefer to start with diet and exercise and turn to drugs if needed. Keep in mind that not all women with PCOS have hyperinsulinemia, but the majority do.

Why Don't The Typical "Low-fat" Weight Loss Diets Work?

Approximately 50 – 60% of women with PCOS are obese. It has been shown that losing even 5% of body weight can lead to an improvement in skin, regularity of menstrual cycles and decreased insulin levels. However many women with PCOS experience difficulty losing weight, possibly due to high insulin levels promoting fat storage. The standard low fat high carbohydrate weight loss diet may not be the best approach for women with PCOS. High intakes of carbohydrates, especially refined carbohydrates (ie. sweets, white bread, white rice, etc.) will quickly turn to sugar and cause elevated levels of insulin. Since high levels of insulin can cause a multitude of problems for women with PCOS, a better diet would be a low glycemic index diet. This is a diet that includes foods or combinations of foods that do not cause a rapid rise in blood sugar. The low glycemic diet will be discussed more in detail later in this article.

How Many Carbohydrates Should You Eat A Day?

At this point in time, I am not aware of any studies that provide data as to the recommended level of carbohydrates for a woman with PCOS. Should you follow a Food Pyramid based diet (55% of calories from carbohydrates – but select mainly from whole grains), a diet which is 40% carbohydrates (ie. The Zone), or a very strict diet that allows only 20% of calories from carbohydrates (ie. Atkins or Protein Power)? In my experience, there is no one level that will work for all women. Dr. Walter Futterweit, clinical professor of the Division of Endocrinology of the Mount Sinai School of Medicine, has been working with women with PCOS for 25 years. He suggests that non-obese women with PCOS who get regular periods eat a balanced diet, moderate - not excessive intakes of carbohydrates (approximately 50% of calories), and select complex unrefined carbohydrates over refined carbohydrates. An obese insulin resistant woman should consume a diet that is 40 % carbohydrates or less, depending upon the degree of insulin resistance. These are only guidelines – the diet should be tailored to fit the individual person. I would suggest starting with a diet that is 40 % carbohydrates and work your way downward if need be. Some subjective indicators that the diet is "working" are: decreased cravings and increased energy levels. Some objective measures that the diet may be working are: weight loss, decreased insulin levels, regular periods. Clearly, this is an area that needs to be researched.

Hazards of Low Carbohydrate Diets That Are High In Saturated Fat

Several of the popular low carbohydrate diets contain as much as 60% of calories from fat, much of it saturated. I do not recommend these diets as saturated fat has been linked to heart disease. These diets could be especially dangerous for women with PCOS, as they already have an increased risk of heart disease. In addition, these diets are low in fiber, vitamins, minerals and disease fighting phytochemicals. Remember that this is not a temporary diet – it is one that you will need to follow long term! Therefore you will need to make it as healthy as possible.

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.

Suggested caloric intakes:

For weight maintenance:

  • Multiply your current weight by an activity factor between 10-20. Use a higher number (15 - 20) if you are younger, moderately overweight or of ideal weight and moderate to very active. The less active and more overweight you are, the lower the number should be, (10-14).

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

Example: A 30 year old female , height: 65", weight:145 pounds, exercises 3 times a week for 45 minutes. She would multiply her weight by 15. Therefore her maintenance caloric needs are approximately 2175 calories a day. To lose one pound a week (subtract 500 calories), she would consume 1675 calories a day. To lose 1 ½ pounds a week (subtract 750 calories), she would consume 1425 calories. It is not recommended that anyone eat less than 1200 calories on a regular basis as this may slow the metabolism as well as be nutritionally inadequate.

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 glycemic index foods as they will cause a slower rise in blood sugar. (Glycemic index is an indicator of how rapidly the food turns to sugar in the blood). The lower glycemic carbohydrates tend to have more fiber than the higher glycemic foods. For example, bran cereal (10 gm fiber/1/2 cup) has a lower glycemic index than cornflakes (1 gm fiber/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. (Note – the Carbohydrate Addicts Diet recommends eating all the carbohydrates at one meal. If this diet helps control food cravings and is promoting weight loss – keep it up! )
  • Avoid those carbohydrates that trigger more hunger or cravings (ie. pasta triggers craving for some people).
  • Suggested vitamin / mineral supplements:
    • calcium 1000 mg – 1500 mg (take two – three 500 mg pills a day and be sure to space them out as you can only absorb 500 mg at a time.)
    • multivitamin with minerals (make sure it contains folic acid(Drug information on folic acid) 400 mcg if trying to get pregnant)
  • Drink at least 8 cups of noncaffeinated fluid as a low carbohydrate intake can cause dehydration.
  • For heart health, limit foods high in saturated and trans fats (ie. fatty red meat, whole milk dairy, butter and stick margarine, chicken skin, fried foods, rich desserts, etc.). Select mainly monounsaturated fats (ie. olive oil(Drug information on 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
  • If on a very low carbohydrate diet, check with your MD regarding a potassium supplement
  • If constipation is a problem, try a natural fiber supplement such as sugar free Fiber all or Metamucil (may have about 2 grams of usable carbohydrate per dose). Be sure to drink plenty of fluids as well.
  • For those women who are interested in counting grams of carbohydrate:
    1. Suggested carbohydrate intake:
      • Calculate your caloric needs, whether it be to maintain or lose weight.
      • Multiply your caloric needs by .4 (this will be a diet that is 40 percent carbohydrate) and then divide by 4 (carbohydrate has 4 calories per gram)
      • If you are obese and insulin resistant, then you may need less that 40% from carbohydrate. Check with your MD or nutritionist.
      • For example: If your caloric needs to lose 1 ½ pounds a week is 1425, then multiply that number by .4and divide by 4 (1424 × .4 = 569 divided by 4 = 142 grams of carbohydrate per day).
    2. Count total grams of carbohydrate – not just grams of sugar. All carbohydrates eventually turn into sugar in the blood.
    3. To count "effective" grams of carbohydrate, subtract the grams of fiber in a food from the total carbohydrate content. For example, 6 whole wheat crackers might have 15 grams of total carbohydrates and 3 grams of fiber. The effective grams of carbohydrate would be 12 grams. This is what you count when you are adding up your grams of carbohydrate.

The following is a meal plan for: 1500 calories / 118 gm effective grams of carbohydrate

Breakfast: One oz. oatmeal (14 gm e.c.)
½ cup cottage cheese (3 gm e.c.)
½ cup blueberries (8 gm e.c.)
Total: 220 calories/ 25 gm e.c.
Lunch: Grilled chicken, 4 oz.
2 cups greens
1 cup assorted vegetables (approximately 5 gm e.c.)
½ cup kidney beans (14 gm e.c.)
1 apple (18 gm e.c.)
2 tsp olive oil, unlimited wine vinegar
Total: 490 calories/37 gm e.c.
Snack: 1 oz low fat mozzarella stick (1 gm e.c.)
6 Finn Crisp crackers (22 gm e.c.)
Total: 180 calories/23 gm e.c.
Dinner: Poached salmon, 5 oz
½ cup spinach (4 gm e.c.)
salad, 1 cup greens, ½ cup assorted vegetables (approximately 3 gm e.c.)
1 tsp olive oil, vinegar
½ cup brown rice (20 gm e.c.)
Total: 485 calories/ 27 gm e.c.
Snack: 1 oz. dry roasted soynuts ( 9 gm e.c.) Total: 134 calories/9 gm e.c.

In conclusion, we know that weight loss is key in decreasing insulin resistance in obese women. It appears that a lower glycemic diet may play an important role in helping to control insulin levels as well as promoting weight loss. However this is an area that needs to be further researched.

 

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by Sabrina Lira | March 14, 2012 3:19 AM EDT

I would really like to Handel my pcos





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