Dietary Interventions for PCOS: One Size Doesn’t Fit All
Before we dive right into dietary management strategies for PCOS, let’s get one thing straight. There is no one-size-fits-all approach to treating/managing PCOS.
What works for one person may not work for another. You are your own unique person both genetically and microbiologically, as well as emotionally and spiritually.
This uniqueness can greatly impact the way you respond to certain environmental changes, such as diet changes, so personalizing your approach to finding a healthy, sustainable eating pattern is essential. You need something that will work for your personal preferences and beliefs, concurrent medical issues, health goals, activity level, and other factors.1
That being said, there are some overall patterns of eating that have proved helpful for most women with PCOS, and making dietary adjustments based on these patterns and principles is a great way to start finding an eating pattern that works for you.
In this blog post, we’re going to look at some of the best nutrition patterns, as shown by science, for managing PCOS.
We’ll also take a peek at some of the most common recommendations made on social media that don’t have much scientific support, and explore why these dietary interventions seem to work so well for some and not for others.
So, let’s dive in!
Do Women with PCOS Eat Differently?
This may seem like an odd question, but when you consider that PCOS is basically a hormonal disruption and that many of our food choices are driven by hormones, it seems more legitimate to ask this. So let’s ask it! Do they?
Based on this information, we can conclude that women with PCOS are probably craving more simple carbohydrates. This is consistent with decreased insulin sensitivity, a condition that affects approximately 75% of lean women with PCOS and 95% of overweight and obese women with PCOS.
Should Women with PCOS Change the Way They Eat?
This is a loaded question. Telling a person they should or should not do something assumes a certain degree of uniformity among people, and it also assumes that the person in question is behaving in a way that needs to be amended.
The truth is that most women with PCOS would benefit from some simple dietary changes, but the extent of the changes needed depends on the individual, not simply on her diagnosis.
It’s also important to note that many women with PCOS are very restrictive in their food choices, which can increase physical stress... which can further drive PCOS symptoms.
Some women need a more regulated diet, and some need a more liberalized diet. The person who can determine this best is the woman herself. So, don’t assume that “dietary changes” automatically means more restrictions, because it might actually mean more freedoms!
Studies have shown that while there’s no one diet that works best for all women with PCOS, there are certain dietary patterns/factors that can help most women with this disorder.1
These dietary patterns include choosing low glycemic-index foods, staying within a low-moderate carbohydrate eating pattern, following a heart-healthy diet, getting lots of fiber, prioritizing fruits, vegetables, and legumes, reducing processed and sugary foods, and timing meals appropriately during the day.1
Dietary Patterns for PCOS
As promised, here are some eating patterns that have proven beneficial for women with PCOS, when studied in randomized controlled trials.
(We like research conducted using these kinds of trials, or tests because the structure of them removes some of the biases from the equation and allows researchers to gain a clearer picture of how the diet affected the study participants.)
1. Low Glycemic-Index Diet
The glycemic index is a measure of how quickly a carbohydrate food spikes blood glucose levels. Higher numbers refer to fast, high spikes, and lower numbers correlate with longer, gentler rises in blood glucose.
In a Low GI diet, a person chooses most of their carbohydrate foods from among those that cause the lowest spike in blood glucose, thereby reducing the impact of glucose on the blood and pancreas which allows insulin to do its job more gradually.
Low GI foods provide a steadier, more constant stream of glucose (aka energy) to cells without overwhelming them.1
Studies have shown that Low GI diets can be very effective at helping to manage insulin resistance, and since insulin resistance is a common condition in, and antagonist of, PCOS, this pattern of eating can be quite helpful.
In fact, one study found that women with PCOS who were following a low GI diet had more than three times as many ovulatory cycles as compared to women with PCOS who were consuming a standard GI diet! 5
6 This image shows the difference in blood glucose spikes between different levels of GI rankings.
Check out this article to learn more about Low GI eating patterns.
2. The Ketogenic Diet
There has been some buzz in the PCOS community recently about a study that showed the Ketogenic Diet to be a very helpful eating pattern for women with PCOS.
The study in question was published in 2020, and it showed significant improvements in metabolic markers for overweight women with PCOS after 12 weeks on the diet.7
For those who may be unfamiliar with the Ketogenic Diet, it’s a high-fat, low-carb, low-to-moderate protein diet that has been used successfully in a variety of clinical settings, including childhood epilepsy and some cases of diabetes.
A traditional Ketogenic Diet is extremely limiting and most pop-culture keto diets are much more forgiving towards both carbs and protein than traditional medical versions of the deit are.
Fans of the Ketogenic Diet have been all about sharing that keto lifestyle with the PCOS community since the publication of this research…but there’s a catch.
The diet in this study was a modified Ketogenic/Mediterranean diet and each participant was also regularly given herbal supplements to help negate the side effects of the diet such as nausea and bad breath.7
Some of the herbs they were given have been shown, in other studies, to exert positive effects on the hormonal and metabolic parameters of women with PCOS. So was the success of this study from the diet or the supplements? We just don’t know.
Also, something to be aware of is that this study's version of the ketogenic diet emphasized healthy fat, while the average Keto Diet just wants fat, ANY fat.
The thing is, saturated and processed fats are very inflammatory, while monounsaturated and polyunsaturated fats are anti-inflammatory. This study chose to emphasize anti-inflammatory fats.7
Because this study provided so many changes at once to a small group of women, and because it didn't have a control group to compare them to, it’s not a very good study to use as a recommendation for lifestyle changes.7
That said, if you want to try the Ketogenic Diet for your PCOS and you have a plan to go about it healthfully, more power to you!
3. Moderate Carbohydrate Diet
In one study, researchers provided women with either a standard diet with a macronutrient breakdown of 55% carbohydrate, 27% fat, and 18% protein or an MC Diet with a macronutrient breakdown of 41% carbohydrate, 40% fat, and 19% protein.1,8
There have been other studies on the effects of carbohydrates on PCOS as well. These studies show that diets resulting in big improvements for women with PCOS typically provide anywhere from 30-60% of daily calories from carbs.1 So, feel free to tweak the ratios of carbs, fats, and proteins to best suit your body and lifestyle.
Just be sure to keep your protein 18% or higher, and make sure your fats are mostly unsaturated.
The lesson here is that healthy carbs are good for you and can be part of a helpful, therapeutic diet. Yay, carbs!
4. DASH Diet
DASH stands for Dietary Approaches to Stop Hypertension and is a whole-foods diet that is low in salt and saturated fat, but high in fruits, vegetables, legumes, and whole grains.
This diet was developed to manage hypertension (high blood pressure) and cardiovascular disease. But, research has shown that the diet actually helps with many factors involved in PCOS.1
One study compared the efficacy of the DASH diet to a standard diet in women with PCOS. Researchers provided both groups of women with the same daily calories and macronutrient breakdown, but the standard diet didn't have the emphasis on fruit, veg, low-fat dairy, and lack of processed, sugary foods that the DASH diet has.9
This study found that the DASH diet resulted in more weight loss, and higher levels of sex hormone-binding globulin (SHBG) compared to the standard diet.9
SHBG helps women to keep testosterone levels lower by grabbing and binding free testosterone when there’s too much of it.
You can find out more about the DASH diet here.
5. Other Diets
There are other diets that may help with PCOS, including the Mediterranean Diet, a High Fiber Diet, and a Whole-Foods Plant-Based Diet.1
All these diets emphasize fruits, vegetables, legumes, nuts, and seeds. They limit processed foods, red meats, dairy products, and sugars. And, they are all full of antioxidants, phytonutrients, fiber, and anti-inflammatory foods that promote good health.
Any diet that can provide lots of high-quality foods like these will likely be helpful in managing your PCOS.
The key to choosing a diet is that it must be sustainable in the long term. PCOS is driven by hormones and hormones are really slow drivers.1
If you want to use dietary changes to help your body, you may have to stick to your changes for several months, or even a year, before you begin to see real benefits. (We know. Just what you wanted to hear.)
This means you must choose to eat in a way that fits well with your food preferences and lifestyle. If that’s a vegan diet, go for it! But, for most of us, it will probably be a Moderate Carbohydrate diet with an emphasis on unsaturated fats, vegetarian protein and/or fish, lots of fruits and vegetables, and the permission to occasionally deviate from the norm to enjoy some birthday cake or holiday pie. (Celebratory desserts are important for most of us!)
I Heard That This Was Something I Had to Do
There are a lot of dietary suggestions out there that social media influencers promote as necessary for women with PCOS.
Some of these suggestions are helpful, some are not, and some are only helpful for a select few, even though they’re promoted as being helpful for all women with PCOS.
In this section, we’ll discuss a couple of common “musts” that aren’t necessarily as imperative as they’re made out to be.
1. “You MUST Do Intermittent Fasting”
We are aware that a lot of people who are trying to manage their weight turn to intermittent fasting, and this can work well for many people. But, it’s not a method we’d recommend to most women with PCOS for a couple of reasons.
Let’s take a peek at a study that examined the relationship between the time of day when calories are eaten and the metabolic outcomes these patterns elicit in women with PCOS.
This study recruited 60 lean women with PCOS. They put all the women on a diet with the exact same number of daily calories, but they separated the women into two groups based on when during the day they got most of their calories.
The 30 women in Group A received 980 calories at breakfast, 640 calories at lunch, and 190 calories at dinner. Those in Group B received 190 calories at breakfast, 640 calories at lunch, and 980 calories at dinner.1,10
Most people’s eating patterns more closely resemble group B, but this may not be a very good thing.
Just from eating their calories mostly in the morning, Group A saw a 7% improvement in blood glucose and a 54% improvement in insulin. Group A also saw their testosterone levels decrease by 50% and their levels of SHBG increase by 105%! Group B didn’t see any of these beneficial changes.1,10
Breakfast is the new dinner, people!
The second reason we recommend caution is that depriving yourself of food for a large portion of the day may exacerbate your carbohydrate cravings and lead to poor food choices and binging. Since women with PCOS are already susceptible to both of these things due to their hormones, intermittent fasting may not be the healthiest option.
With that said, if you want to try intermittent fasting to improve your PCOS, go right ahead, but we strongly encourage you to eat your food in the morning hours rather than in the evening if you want to see big results.
And remember, you’re gonna have to work extra hard to fight the power…of your hormones telling you to eat all the carbs now!
2. “You MUST Eliminate Dairy and/or Gluten”
Do all women with PCOS need to eliminate dairy and gluten from their diets?
A PCOS-friendly diet does not need to be dairy and/or gluten-free.
If you know someone, who benefited from eliminating dairy and gluten from their diet and you’d like to try it too, then by all means, go for it! But if you want to keep those foods in your diet and you tolerate them well, don’t feel pressured to give them up.
There’s not much research on the effects of including or excluding either dairy or gluten in a PCOS-friendly diet.
Most of the evidence to suggest people should avoid these foods is anecdotal, meaning it’s just word-of-mouth testimony from individuals who have experienced good things from cutting them out.
While we’re very happy that these women have found relief from their PCOS symptoms by eliminating dairy/gluten from their diets, it’s a little hasty to assume that all women with PCOS will benefit in the same way.
Let us explain.
The likely reason that many women benefit from cutting out wheat and/or dairy products, is that they have a sensitivity to them.
Food sensitivities are different from food allergies in that they’re not overtly dangerous, but they do still cause an inflammatory response.11
One link between food sensitivities and PCOS is inflammation. We know that women with PCOS have increased levels of inflammation, and we also know that food sensitivities can increase inflammation.1,11
Managing inflammation is a key part of managing PCOS, so discovering any food sensitivities and eliminating those foods from your diet can be a good place to start in creating an individualized, PCOS-friendly diet.
Figuring out food sensitivities can be tricky though because it can take days, or even weeks, after a food is eaten before a physical symptom is experienced.11
Dairy and wheat are among the top allergens in the world and many people who eat them are sensitive to them and don’t know it.11
Other common allergens include soy, tree nuts, eggs, fish, shellfish, sesame, and peanuts.12 But most people don’t just give up these foods without checking to see if they are actually sensitive to them. We recommend the same course of action for dairy and gluten.
Common symptoms of food sensitivities and intolerances include digestive problems like constipation, diarrhea, gas, bloating, and stomach cramps. Other symptoms include rashes, hives, eczema, migraines, excess mucus production, joint pain, and fatigue.11
But remember, the symptoms listed above can take a long time after ingestion before they show up in the body, so figuring out food sensitivities can be really tricky.11
To help you figure out if you have any food sensitivities, we recommend keeping a food and symptom diary that will help you figure out if certain foods are causing problems hours or days later.
Another option is to get an allergy test and make sure your healthcare provider knows you’re looking for sensitivities, not just overt allergies.
The Short, Sweet Version
Overall, the tips for a healthy PCOS diet are to follow an MC diet, include lots of fruits and vegetables, get plenty of fiber, limit processed and sugary foods, and choose an eating pattern that will work for you in the long term.
Eating most of your foods earlier in the day may be quite helpful, especially as opposed to eating the bulk of your calories in the evening.
And, you can try eliminating certain foods if you think that you may be sensitive to them, but you don’t need to cut out foods just because other people have had success doing so.
In parting, remember that eating healthy, whole foods, and lots of plant foods is one of the simplest, safest, and most effective things we can do to promote good health in our bodies. As with every preventative/restorative measure though, sometimes these changes alone are not enough to help our bodies function the way we want or need them to.
If you are struggling with health problems, please contact your doctor or other healthcare provider such as a Naturopathic Doctor, Dietitian, or Mental Health Professional, to see if they can offer appropriate guidance and care. We at Wholesome Story believe that healthy communities require community effort, so we advise you to keep your healthcare community aware and involved in your journey as you pursue better health.
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- Groves Azarro M. Polycystic ovary syndrome: Managing insulin resistance with diet and lifestyle. EatRightStore. https://www.eatrightstore.org/dpg-products/difm/polycystic-ovary-syndrome-managing-insulin-resistance-with-diet-and-lifestyle. Published 2020. Accessed August 31, 2022.
- Shishehgar F, Ramezani Tehrani F, Mirmiran P, Hajian S, Baghestani AR, Moslehi N. Comparison of dietary intake between polycystic ovary syndrome women and controls. Global journal of health science. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5064084/#:~:text=The%20results%20demonstrated%20that%20energy,p%3D0.037. Published September 1, 2016. Accessed August 31, 2022.
- Douglas CC;Norris LE;Oster RA;Darnell BE;Azziz R;Gower BA; Difference in dietary intake between women with polycystic ovary syndrome and healthy controls. Fertility and sterility. https://pubmed.ncbi.nlm.nih.gov/16762348/. Published 2006. Accessed August 31, 2022.
- Szczuko M, Kikut J, Szczuko U, et al. Nutrition strategy and life style in polycystic ovary syndrome-narrative review. Nutrients. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8308732/. Published July 18, 2021. Accessed August 31, 2022.
- Sordia-Hernández LH;Ancer Rodríguez P;Saldivar Rodriguez D;Trejo Guzman S;Servín Zenteno ES;Guerrero González G;Ibarra Patiño R; Effect of a low glycemic diet in patients with polycystic ovary syndrome and anovulation - a randomized controlled trial. Clinical and experimental obstetrics & gynecology. https://pubmed.ncbi.nlm.nih.gov/29734548/. Published 2016. Accessed August 31, 2022.
- Know Diabetes UK. Glycaemic index | know diabetes. Know Diabetes. https://www.knowdiabetes.org.uk/be-healthier/eat-better/glycaemic-index/. Published 2022. Accessed August 31, 2022.
- Paoli A, Mancin L, Giacona MC, Bianco A, Caprio M. Effects of a ketogenic diet in overweight women with polycystic ovary syndrome. Journal of translational medicine. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7045520/. Published February 27, 2020. Accessed August 31, 2022.
- Gower BA, Chandler-Laney PC, Ovalle F, et al. Favourable metabolic effects of a eucaloric lower-carbohydrate diet in women with PCOS. Clinical endocrinology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4111472/. Published October 2013. Accessed August 31, 2022.
- Azadi-Yazdi M;Karimi-Zarchi M;Salehi-Abargouei A;Fallahzadeh H;Nadjarzadeh A; Effects of dietary approach to stop hypertension diet on androgens, antioxidant status and body composition in overweight and obese women with polycystic ovary syndrome: A randomised controlled trial. Journal of human nutrition and dietetics : the official journal of the British Dietetic Association. https://pubmed.ncbi.nlm.nih.gov/28466507/. Published 2017. Accessed August 31, 2022.
- O; JDBMWJF. Effects of caloric intake timing on insulin resistance and hyperandrogenism in lean women with polycystic ovary syndrome. Clinical science (London, England : 1979). https://pubmed.ncbi.nlm.nih.gov/23688334/. Published 2013. Accessed August 31, 2022.
- Henry Ford Health Staff. Is it a food allergy, food sensitivity, food intolerance or celiac disease? Henry Ford LiveWell. https://www.henryford.com/blog/2020/11/is-it-a-food-allergy-food-sensitivity-food-intolerance-or-celiac-disease#:~:text=What%20it%20is%3A%20When%20a,constipation%2C%20diarrhea%20and%20migraine%20headaches. Published 2020. Accessed August 31, 2022.
- Center for Food Safety and Applied Nutrition. Food allergies. U.S. Food and Drug Administration. https://www.fda.gov/food/food-labeling-nutrition/food-allergies. Published 2022. Accessed August 31, 2022.