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PCOS and Insulin Resistance: Part 5.1 A Dietary Approach to PCOS

On my last blog I alluded to the fact that some women, maybe MANY women, with PCOS could help or reverse their condition through dietary and lifestyle modifications. This is not new to the medical community, and most women with PCOS have tried to do just that. It is a known fact that when women with PCOS lose a bit of weight, their condition improves. One of the other most common symptoms of PCOS is irregular menstruation and anovulation. When women with PCOS lose a bit of weight, they seem to improve their changes of conceiving. As such, it makes total sense then that women with PCOS be told to lose weight. The main question here is, how should they lose weight? And, is losing weight really the key to helping women with PCOS?

Obesity is a very prominent feature of PCOS. Although obesity, per se, is not a diagnostic criterion for PCOS, it is a common expression of this condition. Eighty percent of women with PCOS, in the United States, are obese. Furthermore, although we do not believe that obesity itself causes PCOS, its presence seems to significantly complicate the syndrome (symptoms and risk factors). But here’s something: why do thin women with PCOS also seem to improve signs and symptoms when they undergo certain dietary changes, (myself included)? Could it be that the key factor involved is not the weight itself, but something else that affects both the weight and the other prominent features of PCOS?

When I was diagnosed with PCOS, I had gained some weight, about 12 lbs. Not significant. I was by no means obese. I weighed then (with the increase) maybe 115 lbs and my BMI was still around 20 (healthy BMI is between 19-24). This added weight (or whatever caused it) made me stop ovulating and increased my acne. I knew enough then to figure out that whatever was causing the weight gain must also be causing my anovulation, acne and other PCOS symptoms to develop (I also discovered I had polycystic ovaries on ultrasound that year and I was losing hair on my frontal scalp). Yup, you guessed it. My insulin was higher (hyperinsulinemia). I had developed Insulin Resistance. I didn’t know it then, but I did find out a few years later (when I tried to get pregnant a second time).

It wasn’t obesity that caused me to develop PCOS (I was never obese), but another factor (insulin) was causing me to start gaining weigh at galloping speed and all the other PCOS symptoms (anovulation, acne, hirsutism, a growing belly, scalp hair loss…). At this point, I could not ovulate, and so I could not have babies, which was what I wanted more than anything in this world. I put 2+2 together and figured that losing weight, even though that wasn’t my main issue, might help me. My doctor even said so.

At the time, I worked as a Naturopathic Doctor in Mozambique. I put people through diets for a living. I prescribed a Base Diet (a moderate to liberal low carb diet, similar to a Paleo Diet or the Whole30 concept) which included “healthy snacks” for the majority of the month, and then I would throw in a Detox (a strict low carb, similar to a Keto diet) and no snacks for 7 days out of the month. When I was diagnosed with PCOS, and decided that if I lost some weight I might get pregnant, I went for the bull’s eye: I chose to do the Detox diet (more is always better for me, I am an “all or nothing” kind of person, lol). I had never heard of Keto back then, this was 8 years ago. I made up these diets as I went. I have mentioned that my Mozambican patients were my “guinea pigs” and truly wonderful and forgiving people. I knew these diets worked and helped my patients lose weight and feel better. Up until then, I prescribed these diets to people, but I never followed them myself. What for???? I wasn’t overweight or obese, right?

Long story short, that month I lost 2.5 kg (5.5 lbs), I ovulated within a month and I got pregnant with my first child, Zinzi.


Figure 1: Zinzi

Unbeknownst to me then, this Detox diet (aka strict low carb, keto diet) decreased my insulin status enough to help me lose weight, ovulate, and clear up most of my acne. All I knew was that whatever helped me to lose weight, also helped me get pregnant. I will tell you now, that once I got pregnant, I threw the diet right out the window…fast-forward to all my pregnancy and post-pregnancy complications (and fertility issues 2 years later).

The dietary approach most practitioners today recommend for women with PCOS, or any other person that needs to lose weight, is a calorie-restricted diet. This diet is based on the “calories in, calories out” theory (CICO). This means that you must “eat less and move more” to lose weight. I won’t reference any CICO diets here because I really don’t want to lead you astray (in my opinion), but from a macronutrient (Carbs, Protein and Fat) perspective, this would mean that you would eat nutrients that are lower in calories, and avoid those that are higher, eat less quantities in general, and exercise more. From a caloric perspective, Carbs and Protein have 4 calories/g and Fat has 9 calories/g. Whoa! Fat has more than double the calories per gram versus Carbohydrates and Protein. If you follow a CICO diet, you would be instructed to eat more carbs and protein and less fat. That seems obvious. Don’t forget that you are also trying to eat less quantity overall. If you read most self-help guides on PCOS, or speak to a conventional nutritionist, this is still the recommended approach. Women are told, eat a low calorie, low fat diet, small meals, many times a day.

Had I chosen this conventional dietary method, rather than the one I followed, knowing what I know today, do I believe I would have gotten pregnant? Maybe. I probably would have lost some weight. A calorie-restricted diet, at least initially, seems to help people lose a bit of weight. But then, it seems the weight loss stalls. In very simple terms this is because, eventually, your metabolism adapts. Dr. Fung explains this perfectly in his first book, The Obesity Code. If you eat less, your body will “burn” less, it’s that simple. "But then you just exercise more" they say, right? Wrong! You exercise more (i.e. burn more), you need to eat more (i.e. feel more hungry)! For anyone that has ever tried this approach (most of us!), this feels like starvation! So not only does it stop working after a while, it is pure torture!

But the question remains: would I have gotten pregnant with a low-calorie approach rather than a low-carb diet? In other words, besides losing weight, would I have begun to ovulate again? Well…maybe. In order to assess this, you must understand Insulin’s function as a Metabolic and Reproductive Hormone. Forty to 70% of women with PCOS have Insulin Resistance/Hyperinsulinemia. The Pathophysiology of PCOS (Figure 2) is described as a “vicious circle” where higher levels of insulin (hyperinsulinemia) contribute to both metabolic expressions (i.e. larger fat cells) as well as reproductive ones (abnormal male hormone levels) and increased sympathetic nerve activity. All these factors in turn feedback and cause a further increase in insulin production, and the cycle goes on and on. Insulin is involved in both weight gain and fertility. A decrease in insulin production contributes to both weight loss and ovulation.

Figure 2: Pathophysiology of PCOS

Would a low-calorie diet (or the weight loss achieved through this diet) contribute to decreasing levels of insulin? Possibly. The weight loss would, to some extent. A low-calorie diet might, as well. If the diet is lower in the macronutrients that most contribute to insulin production, then yes. If this low-calorie diet, however, is high in carbs, then NO! Carbs are low-calorie macronutrients, remember? There are only 4 calories/g of carbs versus 9 calories/g of fat. Therefore, it is possible to consume a low-calorie diet that is high in carbs (and most people do). Problem here is that carbohydrates are the macronutrients that produce the highest insulin response. Protein (which is also lower in calories than fat) produce a moderate insulin response, and Fat (which is a high-calorie macronutrient) produces an insignificant insulin response. A diet high in carbs, and low in fat (calorie-restricted diet) will contribute to hyperinsulinemia. This would not have helped me ovulate. If that doesn’t make sense to you, I urge you to read Dr. Fung’s The Obesity Code.

Would the advice to “eat small amounts, many times a day” (aka “healthy” snacks), have contributed to decreasing my hyperinsulinemia/insulin resistance and in turn helped me lose weight and/or ovulate? Regardless of what we eat, every time we eat, we produce an insulin response, i.e. insulin rises. The less often you eat, the less insulin you produce, and the lower your overall insulin status. So, HECK NO! Snacking all day long would NOT have helped ME lose weight or ovulate. That’s what got me in trouble in the first place! If I haven’t already mentioned this, let me tell you: until about the age of 30, I never had a full meal MY ENTIRE LIFE. I lived on “healthy snacks”. Fast-forward 30 years and I developed insulin resistance and PCOS!

What about the potentially 30-60% of women with PCOS that do not have insulin resistance? These may be the women that do ovulate and become pregnant! These may also be the women that have PCO (polycystic ovaries) but not hyperandrogenism (high male hormones). These are different expressions of PCOS. These women have a less advanced phenotype thought to be a transitional one. These PCOS women, with normal insulin function, a normal metabolism and normal reproductive system (for now), are thought to eventually develop insulin resistance (and everything that comes with it) as the condition progresses: obesity, hyperandrogenism, anovulation and are at an increased risk for diabetes, cardiovascular disease, and cancer. It seems obvious then, that even these women would be wise to prevent the condition from progressing, or attempt to reverse it entirely.

Lastly, I am well aware that not all women with PCOS are trying to get pregnant (as I was). If you are thinking that the correct dietary approach for these women (who are not trying to get pregnant, but simply want to improve their acne, excessive hair growth, dark skin folds, and excessive weight) might be different, please review Figure 2 again.


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