Dietary Interventions For PCOS
Updated: Jul 26
What is PCOS?
In laymans terms PCOS (Polycystic ovary syndrome) is a condition that affects a woman’s hormone levels. It is a “syndrome,” or group of symptoms that affects the ovaries and ovulation. Its three main features are:
cysts in the ovaries
high levels of male hormones
irregular or skipped periods
In PCOS, many small, fluid-filled sacs grow inside the ovaries, which is where the word “polycystic” comes from. It literally means “many cysts.” These sacs are actually follicles, each one containing an immature egg, but the eggs never mature enough to trigger ovulation.
The lack of ovulation alters levels of estrogen, progesterone, FSH (follicle stimulating hormone), and LH (luteinizing hormone). Women with PCOS tend to have lower levels of estrogen and progesterone coupled with highler levels of androgens. Because they have an excess of male hormones it disrupts the menstrual cycle, so women with PCOS tend to get fewer periods than usual.
Additional symptoms of PCOS include:
Common symptoms of PCOS include:
difficulty getting pregnant (because of irregular ovulation or failure to ovulate)
excessive hair growth usually on the face, chest, back or buttocks
thinning hair and hair loss from the head
oily skin and acne
Insulin resistance, heart disease and diabetes have all been linked to PCOS due to excess androgens.
Medical journals routinely state that the exact cause of PCOS is yet to be identified. It has been shown to run in families, but it's likely that multiple genes, not "one" gene contribute to it.
From a practical perspective the cause of PCOS symptoms boils down to two main mechanisms: high androgen levels (testosterone being the most famous androgen), and chronic low grade inflammation. It doesn’t matter if you have PCOS and you’re relatively slim, or your PCOS is expressed with the more classical phenotype where you gain weight easily, these two things are responsible for ALL PCOS symptoms.
So the first thing to consider is how you can best adjust the diet to help LOWER androgen levels.
Androgens interact with all other hormones to impact fertility, to cause weight gain, to promote adult acne, to give enough hair in the right places, while providing extra hair in the wrong places and so on.
Androgen levels work in unison with insulin levels. So when insulin goes up, so too does testosterone. And insulin happens to be the hormone that makes the body store fat which is why a lot of women with PCOS find it nearly impossible to lose weight, and while many also often accumulate excess stomach fat despite being otherwise thin.
So since insulin levels are largely controlled by what and how you eat, by making adjustments to your diet you can eat in a way that keeps insulin levels lower. This in turn helps PCOS symptoms (including weight loss) improve.
And as far as low grade inflammation, what that basically means is that the immune system is constantly on high alert.
Inflammation is a major contribution to many of the daily health issues so common amongst women with PCOS like bloating, sinus congestion, low energy, brain fog, sore joints, insomnia, anxiety and depression, etc. And these symptoms can be alleviated with diet intervention, if you opt to avoid pro inflammatory foods.
In short, work to manage your insulin levels and avoid inflammatory foods.
The one thing I feel I do need to hammer home when it comes to PCOS is that caloric restriction isn't always the best option, even if you want to lose weight.
If you understand that body fat accumulates because of poor insulin regulation and NOT because of excess energy in the diet, then it should be pretty obvious that restrictive dieting is a mute point.
Vegetarian & VLC diet approaches for PCOS
I also am not a fan of throwing women who have PCOS on a vegetarian or excessively low carbohydrate diet.
I'm aware keto for PCOS has some significant science behind it, but the resulting health benefits are usually due to improvements in insulin regulation, and these same benefits can ( I believe) be achieved without “going keto". I believe keto (when implemented properly) can work well depending on the context, but I do feel for most people it lacks sustainability.It's a diet that feels more like a DIET and less like a way of eating. And for women wanting a long-term sustainable cure for their PCOS, being “on a diet” for the rest of your life is hardly an acceptable solution. The food restrictions required to keep your body in ketosis can mean calculated careful math before taking every bite, which is part of why most people can’t sustain keto long term.
Keto can also cause thyroid malfunction in women which I've previously discussed on my other social media platforms in the past. Given that hypothyroidism can be a common problem for women with PCOS, I'd rather not.
The thyroid gland produces two hormones: Thyroxine (T4) and Triiodothyronine (T3) which are both necessary for a wife range of bodily function like breathing, heart rate, nevous system, bodyweight, temperature control, cholesterol levels and menstruation.
T3 happens to be very sensitive to calorie and carb intake. If calories or carbs drop too low two things happen: 1) your T3 DROPS and 2) Reverse T3 (rT3) increases. rT3 happens to be a hormone that BLOCKS the action of T3.
Some studies have shown that ketogenic diets can reduce T3 levels by as much as 47% in just two weeks of consuming less then 50g carb a day. By contrast people cconsuming the same calories but at least 50g carb a day saw NO drop in T3. This matters because low T3 and high rT3 can slow your metabolism, and in the case of PCOS, make matters worse.
And as far as vegetarian, or even plant based- sure it can be done but I don't think it's optimal. In general I tend to be a firm believe that the healthiest nutritional strategy is one that incorporates the best of what plant and animal nutrition can offer.
For starters eating seafood, fish, animal meat, and eggs is a guaranteed way to ensure you’re getting adequate amounts of all nine essential amino acids. Sure you can do this by eating a wide range of different plant based foods every day, but you need to be exceptionally skilled at it to avoid an amino acid inadequacy while also keeping your carb intake controlled and of the vegetarians I know none seem to do it successfully.
What's more, protein from animal sources are highly bioavailable whereas plant derived alternatives are not. Remember that PCOS means having a compromised immune system and 70% of your immune system is in your gut so the bioavailability of your food is crucial.
Instead, I always encourage the women I work with who have PCOS to keep it simple and focus on consuming WHOLE, nutrient dense, LOW inflammatory foods. We avoid processed and refined foods as much as possible.
The problem with processed foods and PCOS is threefold. The first problem is that if you’re eating processed foods, you’re not taking advantage of all that nutrition has to offer which can help heal your PCOS. And as a general rule, processed foods contain pro-inflammatory ingredients that make your symptoms worse. The worst of these are vegetable oils and sugar. Sugar in particular is horrible for PCOS. It causes your body to store rather than burn fat, promotes unwanted facial hair, acne, and male-pattern baldness, and it makes you feel like crap emotionally.
This includes fruit. Fructose is sugar too. And while yes it contains fiber and phytonutrients which can offset some of the damage, fruit should still be kept minimal. I recommend having only moderate amounts of whole fresh fruit and avoiding ALL fruit juices, canned fruit, or processed fruit concentrates. Also make sure to choose fruits that lean towards a tart taste and avoid those that are super sweet as that's an indicator of sugar content. In other words berries and melon over grapes and bananas.
By simply avoiding sugar and processed food, you automatically lower carbohydrate intake which is part of managing PCOS. In other words, eat "low carb and slow carb" (but not NO carb). I've worked with a few PCOS women and I try to keep carb intake (depending upon activity) around 20-25% of daily calories. This is still "low” but is greater than that recommended for VLC keto diets.
Keeping carbohydrate intake “low” reduces the amount of insulin the body needs to produce. Since elevated insulin levels are a major driving force for almost ALL PCOS symptoms this one’s a no-brainer.
Also, having some carbs in your system is the best way to stave off sugar and carb cravings. As I mentioned before, quitting sugar is one of the most powerful steps for beating PCOS, yet it’s incredibly difficult because it’s so addictive. Our bodies and brains are hard-wired to run on carbs and when you take them away, you can expect a physiological rebellion. Eating a small amount of complex, unprocessed carbohydrate with every meal is a great strategy for making this essential step easier and more sustainable long term. It's about eating the RIGHT carbs.
While I have some major issues with the use of the glycemic index, in this case I think it's useful to help guide carb choices. Low GI or slow carbs cause your blood glucose levels to rise in a controlled manner, which means the demand for insulin, whose job it is to move the glucose out of your bloodstream and into your cells, is nice and manageable.
Good options are starchy vegetables like sweet potato, yams, and squash. Beans and lentils are another great whole food carb if tolerated, also quinoa, buckwheat, or red, black or wild rice.
I also always suggest a higher protein intake because protein staves off cravings and promotes satiety. If you’re the kind of person that finds it hard not to snack, then there’s a good chance you’re not getting enough bioavailable protein in your diet. Hunger and fullness hormones are cued by protein but not by sugar and carbs. When you eat good sources of protein you feel fuller, longer.
Also - getting enough fats is key. Eating more fat is the other side to the low carb coin, and a healthy intake of fat has been shown to help with weight loss, ovulation, and to even reduce the effects of acne. Avoid processed fats like vegetable oils which are not really from vegetables at all, but rather are processed seed oils coming from soybeans, sunflower, corn, canola, cottonseed, and safflower etc. The reason these oils are inflammatory is because they have high ratios of omega-6 fatty acids. They can also contain industrial trans fats as a result of how they’re made. Opt for healthy saturated fats and omega 3s. Coconut oil, ghee, olives and olive oil, nuts, avocado, etc are all good ideas.
In addition to these suggestions I usually advocate avoiding gluten and dairy as they are pro inflammatory foods.
And it also does help to minimize alcohol and caffeine intake. Moving away from coffee and alcohol also makes it easier to avoid sugar and empty carbs which are often found in these drinks. Alcohol is kind of self explanatory, but caffeine not so much. The reason I say minimize it is because caffeine increases your stress hormones which in turn increases your insulin levels. It can also (depending on the amount) decrease your insulin sensitivity making it more difficult to regulate your blood sugar levels. The acidity of coffee causes digestive discomfort, indigestion, heart burn and imbalances in our gut microbiome and caffeine can disrupt sleep and promotes anxiety.