5 Best Fish for PCOS Weight Loss: How I Lost 40 kg With These Superfoods!

“The Brain Fog & Bone-Tiredness: What PCOS Winters Taught Me”

“Before I lost 40 kg, my life felt like it was stuck in a permanent fog. If you’ve ever lived through a grey UK winter or a freezing USA East Coast January, you know that bone-deep tiredness—but with PCOS, it was 10 times worse. I’d wake up exhausted, my brain felt ‘cloudy’, and I had zero motivation to even go for a walk.

What I didn’t realise back then was that my body was starving for vitamin D and omega-3s. Once I started prioritising fatty fish, it was like someone finally turned the lights on in my brain. My energy levels stabilised, the afternoon slumps disappeared, and for the first time in years, the ‘brain fog’ lifted. It wasn’t just weight I was losing; I was finally getting my spark back.”

The 40kg Transformation: Where It All Began

Losing weight with PCOS isn’t about starvation; it’s about hormonal alignment. When I was at my heaviest, I tried every generic diet, but nothing worked until I fixed my insulin resistance. The turning point? I stopped focusing on “low fat” and started focusing on anti-inflammatory proteins. In this guide, I’m sharing the exact seafood and superfoods that helped me drop 40 kg and finally take control of my metabolic health.

Why Fish is the Ultimate PCOS “Medicine”

Most women with PCOS suffer from chronic, low-grade inflammation. This inflammation makes your body hold onto fat. Fish (especially oily varieties) is rich in omega-3 fatty acids, which act as a biological switch to:

1. Lower Testosterone: Reducing facial hair and acne.
2. Sensitize Insulin: Helping your cells use glucose instead of storing it as belly fat.
3. Boost Mood: Fighting the “PCOS Blues” and Anxiety.

The “Keto Expert” Fish List (UK Supermarket Edition)

Supermarket Secrets: Where I Shop for PCOS-Friendly Seafood (UK & USA)”

“I’m often asked, ‘But where do you actually buy this stuff without breaking the bank?’ Since I want this to be a worldwide guide, here are my go-tos:

In the UK: For daily staples, you cannot beat Aldi’s ‘Northern Catch’ range for tinned mackerel—it’s cheap and high quality. If you’re looking for tinned sardines that actually taste premium, look for Princes Mackerel or John West. For fresh salmon, Lidl’s Deluxe range is surprisingly good for the price!

In the USA: If you have a membership, Kirkland Signature (Costco) Wild-Caught Salmon is the absolute gold standard for value and health. For my canned fish lovers, look for King Oscar or Season brand sardines—they are cleaned perfectly and packed in high-quality olive oil. At a regular grocery store like Trader Joe’s, their frozen seafood section is a ‘hidden gem’ for budget-friendly PCOS meal prep.”

5 PCOS Superfoods to Pair with Fish

To crack the PCOS weight loss code, your plate needs more than just protein. These 5 superfoods are essential for 2026 metabolic health:

1. Spinach (The Magnesium King): Magnesium is the #1 mineral for stopping sugar cravings. Sauté your spinach in olive oil to maximize absorption.
2. Chia Seeds (Fibre Powerhouse): Oestrogen dominance is common in PCOS. Fibre from chia seeds helps flush out excess hormones and fixes “keto constipation”.
3. Walnuts (The Hormone Nut): Research shows walnuts improve the SHBG protein, which “mops up” excess testosterone in your blood.
4. Avocados: Rich in potassium and healthy monounsaturated fats to keep you full for 6+ hours.
5. Broccoli (The Detoxifier): Contains DIM, a compound that helps the liver detoxify harmful oestrogens that cause stubborn fat.

Recipe: The 15-Minute “PCOS Reset” Traybake

• Ingredients: 2 salmon fillets, 1 bunch of asparagus, 1 cup of cherry tomatoes, lemon, garlic, and olive oil.
• Method: Season everything on a single tray. Bake at 200°C for 12-15 minutes. Serve with a side of fresh spinach. This is the exact meal that powered my 40 kg journey.

Summary Table

• Protein: 3-4 servings of oily fish per week.
• Veg: 2 cups of leafy greens daily.
• Fats: Use olive oil or avocado oil (avoid seed oils).
• The Goal: Reduce inflammation to trigger fat loss.

The Silent Saboteurs: Hidden Inflammatory Oils to Avoid

When I was in the middle of my 40 kg (88 lb) weight loss journey, I made a huge mistake: I was eating healthy salmon but cooking it in the wrong fats. In the UK and USA, most processed vegetable oils are loaded with omega-6 fatty acids. While we need some omega-6, an excess of it creates a “pro-inflammatory” environment—which is like adding fuel to the PCOS fire.

To keep your insulin low and your skin clear, you must clear your pantry of these “seed oils”:

• Sunflower & Vegetable Oil: Extremely common in UK kitchens but highly processed and inflammatory.
• Canola/Rapeseed Oil: (Unless it is “Cold-Pressed”). Most cheap rapeseed oils are processed with high heat that destroys their nutritional value.
• Soybean & Corn Oil: Very common in USA processed foods and “butter substitutes“. These can disrupt your oestrogen balance.

What should you use instead?

To get the best results for your hormones, stick to these stable fats that can handle the heat of cooking your fish:

1. Extra Virgin Olive Oil: Best for low-heat sautéing or drizzling over your spinach.
2. Avocado Oil: The “Holy Grail” for high-heat roasting and air-frying. It has a high smoke point and is packed with heart-healthy monounsaturated fats.
3. Grass-Fed Butter or Ghee: Perfect for adding a rich flavour to white fish like cod. Ghee is especially great, as it contains butyrate, which helps heal the “leaky gut” often associated with PCOS.
4. Coconut Oil: Great for a metabolic boost, though use it in moderation if you are watching total calorie density.

Expert Tip: When buying canned or tinned fish, always read the label. If it says “In Vegetable Oil” or “In Sunflower Oil”, put it back. Only buy fish canned in “spring water” or “extra virgin olive oil”. This small change can double your rate of weight loss by cutting out unnecessary inflammation. Check out my favourite recipes that I made budget-friendly and time-saving and that taste amazing!

“The ‘No-Fishy-Smell’ Secret: My Personal Kitchen Hacks”

• Salmon: “To get that restaurant-style crispy skin, always pat the fish bone-dry with a paper towel before cooking. If you’re in a rush, 8 minutes in the air fryer at 200°C (400°F) is the sweet spot for a juicy fillet.”
• Mackerel: “I know some people find mackerel too ‘fishy’. My secret? Soak the fillets in a little milk or a squeeze of fresh lemon juice for 10 minutes before cooking. It neutralises the strong scent completely!”
• Sardines: “Don’t just eat them out of the tin! Mash them with a fork, add plenty of black pepper, and spread them on a slice of keto-friendly seed bread. It’s a total game-changer for lunch.”
• White Fish (Cod/Haddock): “These are delicate! I love to bake them inside a ‘parchment paper pouch’ with a knob of grass-fed butter and some herbs. It steams the fish in its own juices, so it never gets dry.”

Community Corner: Your Top PCOS & Keto Questions Answered

Q1: Is salmon good for PCOS weight loss?

A. Yes! Salmon is rich in omega-3 fatty acids and vitamin D, both of which are crucial for reducing inflammation and improving insulin sensitivity in women with PCOS.

Q2: Which fish should be avoided in PCOS?

A. Avoid breaded or fried fish often found in frozen aisles. Also, limit high-mercury fish like shark or king mackerel. Stick to “SMASH” fish (salmon, mackerel, anchovies, sardines, and herring).

Q3: Can I eat tinned tuna on Keto for PCOS?

A. Yes, but in moderation due to mercury levels. Always choose tuna in spring water or olive oil rather than sunflower oil to keep inflammation low.

Q: Can I eat Goldfish crackers on keto?

A. No. Goldfish crackers are made from enriched wheat flour (high carbs). They will spike insulin. For a crunch, choose Parmesan crisps or salted walnuts.

Q: Is canned tuna okay for PCOS?

A. Yes, but limit it to 1-2 times a week due to mercury. Choose tuna in spring water or olive oil, never sunflower/seed oils.

Q: How often should I eat fish for PCOS?

A. Aim for 2 to 3 times per week to see a significant drop in inflammation and improved skin health.

Does tinned mackerel have the same benefits as fresh?

A. Yes! Tinned mackerel is often just as nutritious and much more budget-friendly in the UK. Just ensure it is canned in brine, spring water, or olive oil—avoid tomato sauce or sunflower oil, as they often contain hidden sugars or inflammatory fats.

The “Competitive Edge” Conclusion: Beyond the Plate

“Here is the truth that most diet plans won’t tell you: losing 40 kg (88 lbs) wasn’t just about the salmon or the walnuts—it was about choosing myself every single morning. PCOS tries to steal your energy and your confidence, but every omega-3-rich meal you prep is a silent rebellion against your symptoms.

Don’t aim for a ‘perfect’ plate starting tomorrow. Aim for a better one. If you can only manage one tin of mackerel this week, that is a win. If you swapped sunflower oil for olive oil today, that is a win. You aren’t just eating to lose weight; you are eating to heal your hormones and reclaim your life. I’ve been where you are—in the fog, tired, and frustrated—and I’m telling you, the view from the other side is worth every single bite of broccoli. You’ve got this, and I’m right here with you.”

“Are you struggling with a specific PCOS symptom while on keto? Drop a comment below or send me an email—let’s crack your code together!”