Before we dive into this topic, let me say something important.
Even though science-based evidence points in certain directions, I always recommend you to follow what feels right for your body and what is actually sustainable for you. There is no one-size-fits-all approach, especially with something as complex and individual as PCOS.
That said, it’s helpful to look at these diets as tools—not rules. If something aligns with your lifestyle and brings positive changes in weight, energy, or insulin sensitivity, then it’s worth exploring.
Now, let’s break down what the evidence says about Keto, Paleo, and Low-Carb diets in the context of PCOS.
What Is the Keto Diet
The ketogenic diet is a very low-carb, high-fat, and moderate-protein diet. Its goal is to shift your body into a state called ketosis, where it burns fat for energy instead of carbohydrates.
What Does the Research Say?
A 2024 systematic review and meta-analysis focused on overweight and/or obese women with PCOS found significant improvements after following a keto diet:
- 🧍♀️ Average weight loss: 9.13 kg
- 📉 Decrease in BMI and waist circumference
- 🧈 Reduction in fat mass
Another 2005 pilot study showed that a 24-week ketogenic diet led to:
- 12% reduction in body weight
- 22% decrease in free testosterone levels
- 36% reduction in the LH/FSH ratio
- 54% drop in fasting insulin levels
📄 View the 2024 study
📄 View the 2005 pilot study
Side Effects of the Keto Diet
While keto can offer major benefits, it’s not without challenges, especially in the beginning. Some common side effects include:
- Headaches, fatigue, or “keto flu” in the beginning
- Constipation or digestive issues
- Nutrient deficiencies (due to food restriction)
- Social or emotional challenges (especially eating out)
- Difficulty maintaining long-term for many people
What Is the Paleo Diet?
The paleo diet (short for “Paleolithic”) is based on eating whole, unprocessed foods—similar to what our ancestors might have eaten. It eliminates:
- Grains
- Legumes
- Dairy
- Processed sugars
And focuses on:
- Lean meats & fish
- Vegetables & fruits
- Nuts & seeds
- Healthy fats
🔬 What About Paleo and PCOS?
There’s limited direct research on paleo for PCOS. However, low glycemic index (GI) and unprocessed food-based diets (like paleo) have shown improvements in:
- Insulin sensitivity
- Menstrual regularity
- Energy and satiety
Side Effects of the Paleo Diet
The paleo diet focuses on real, whole foods. But cutting out entire food groups can also bring potential downsides. Things to watch out for:
- May lack calcium and vitamin D (due to dairy elimination)
- Can be expensive or hard to maintain socially
- Restricting food groups may lead to nutrient gaps if not well-planned
- Risk of overconsuming animal protein or saturated fats in some cases
What Are Low-Carbohydrate Diets?
Low-carb diets typically restrict carbs to under 45% of daily intake. This can range from moderate low-carb (like 100–130g per day) to more restrictive versions.
What the Research Says:
A 2019 meta-analysis found that low-carb diets significantly improved:
- Body mass index (BMI)
- Insulin resistance (HOMA-IR)
- Total testosterone
- Lipid profile
Side Effects of Low-Carb Diets
Lowering carbs can be a game changer for some women with PCOS, but it’s not without its adjustment period. Here are a few common side effects:
- Fatigue or brain fog in the beginning
- Cravings, especially if fiber intake is low
- Possible constipation
- Risk of nutrient deficiencies without variety
- May trigger binge cycles or disordered eating patterns in some individuals
Considerations & Recommendations
Let’s wrap up with some key takeaways:
✔️ 1. Personalization is Key
What works for someone else may not be right for you. If low-carb or keto makes you feel drained, it’s not your path. Choose a sustainable approach that you can stick with in the long run.
✔️ 2. Focus on Quality, Not Just Macros
Instead of obsessing over carbs vs fats, focus on:
- Whole foods
- Protein with every meal
- Fiber and healthy fats
- Minimizing sugar and ultra-processed snacks
✔️ 3. Avoid Extremes Without Guidance
If you decide to try keto or paleo, make sure:
- You’re getting enough nutrients
- You’re hydrating well
- You’re not over-restricting (especially if you have a history of disordered eating)
- Consider working with a coach or dietitian for support.
✔️ 4. Movement, Stress, and Sleep Matter Too
No diet alone can “fix” PCOS. Lifestyle factors like stress management, good sleep, regular movement, and mindset are just as important.
Final Thoughts
Keto, paleo, and low-carb diets are tools in the PCOS toolbox—not the whole solution. The real magic lies in finding a lifestyle rhythm that nourishes you, balances your hormones, and feels sustainable long-term.
If something in this blog resonates with you and you’re curious to explore it safely, I’d love to help guide you with a plan that aligns with you.
