Fish on a Ketogenic Diet: What to Watch Out For

By June 27, 2021

Fish on Keto and Leanne Vogel

Rapidly increasing levels of toxicity in our oceans have made safe fish harder to come by. However, fish is rich in micronutrients that make it a great option… so, what’s the answer? Should we, or should we not eat fish?

Health Benefits | Mercury | Farmed Fish | Recipes | Buying Fish

I never used to like fish. Growing up in Calgary, Alberta (read: the prairies) there was ZERO options for me to enjoy fresh-caught fish. And, so, I didn’t like the fish I had, and chose not to eat it. This was until I moved on to a sailboat in the Caribbean… talk about fish options!

However, not all are created equal… though, fresh fish is tasty!

A lot of people shy away from fish because of the fishy taste. I got news for you: that’s not normal! Fish shouldn’t taste fishy… at all! And, if you choose the right fish it not only will taste good, but has the promise to benefit your health a bit, too.

I like incorporating fish into my ketogenic diet to boost omega-3 intake, adjust protein intake, and add some variety to my protein so that I don’t develop an allergy to beef. Side note: this is a huge concern of mine. I LOVE beef and couldn’t imagine my life without it. For someone like me who has a propensity toward developing food allergies, I like to add rotation to my diet so my favorite foods like beef, almonds, and coconut, don’t begin causing a reaction in me.

First, let’s go through the benefits of fish, and then we’ll talk about the concerns, and the options I like to stay safe.

Health Benefits of Fish

Not only are fish rich in nutrients, but in the very nutrients that many of us are lacking… specifically, iodine. Low iodine levels are associated with increased risk of hypothyroid symptoms and imbalance of the thyroid. As someone who works to manage her thyroid health, fish is a must for me!

Additional nutrients in fish include vitamin D and omega-3 fatty acids. Two important components that are crucial for optimal brain function and hormonal support.

The Dark Side of Fish: Mercury

Mercury is a significant concern in fish, especially predatory fish. Mercury is a neurotoxin and can have severe effects on your brain and nervous system.

Here are the safe fish you want to gravitate toward if mercury is a concern for you:

Low Level of Mercury

  • Salmon
  • Sardines
  • Pollock
  • Flounders
  • Cod
  • Tilapia
  • Squid
  • Mussels
  • Anchovies
  • Shrimp
  • Oysters
  • Clams
  • Scallops
  • Crab

If you’re going to eat fish, the WHO and CDC recommend limiting yourself to no more than one serving of high mercury fish like tuna per week. That includes both light tuna and albacore. In my opinion? I aim to have high-mercury fish no more than a couple of times a year, if that.

Be aware that the following fish have the highest levels of mercury:

High Level of Mercury

  • King mackerel
  • Marlin
  • Orange roughy
  • Shark
  • Swordfish
  • Tilefish
  • Ahi tuna
  • Bigeye tuna

Avoiding fish is certainly one way to avoid mercury or PCBs. But is that the wisest choice, given the benefits of eating fish? I think it’s striking a balance. I personally choose not to eat fish with high levels of mercury, and when I do eat fish (about twice a week) I go for wild caught options. This choice reduces my PCB intake considerably, lowering cancer risk, while also supporting my heart health because of the omega-3 intake.

Why We Don’t Want to Eat Farmed Fish

Unfortunately, farm raised fish are not a good option. It’s really important that you find a source of fish that’s wild-caught and not farm-raised. Why?

The concern with farmed fish is their diet as well as their toxic exposure. The fish food pellets which they’re fed consist mostly of chicken, wheat, corn and soy, ingredients which are obviously far from what a fish would eat in the wild. Fish that are fed a high fat diet in fish farms also contain fat soluble toxins such as PCB’s, or polychlorinated biphenyls. These are introduced into the animal at a higher rate making the fish themselves much more toxic to the person eating them.

Getting Hung Up on the Prep?

When I started eating fish, I was a bit unclear on how to cook it properly. If that’s you, I’ve included some of my favorite ways to prep!

Crab Boil in a Bag

Air Fryer Rockfish

Jalapeno Glazed Salmon

What to Look for and Where to Purchase

So far, we’ve covered which fish are safest when considering mercury content, how to prepare, and a strong warning to avoid farm-raised fish. Lastly, I need to give you the low-down on where to purchase!

This is the easiest part! If you’re in love with the idea of meat delivery to your door, I have a suggestion for ya: FISH delivery to your door!

Wild Alaskan Seafood Box have monthly subscription options where wild-caught fish is delivered to your door, every month. And, because it’s on a subscription basis, you save money. Each monthly box works out to be 13 servings, $10 a serving, and $130 a month.

The Red & White box is a combo of salmon and whitefish filets.

The Salmon box is, well, you guessed it: all salmon!

The Whitefish box is… all white fish!

Get FREE SCALLOPS with every single order when you subscribe to Wild Alaskan Seafood Box.

Use code KDP to get free scallops added to all of your orders when you sign up for a monthly box.

Fish Box

What’s the whitefish? When I ordered, it’s been rockfish which is a pacific perch. While it’s lower in mercury than tuna, it’s higher than salmon. When I order again, I plan to get the salmon-only box… because the salmon is so good.

And, each large salmon filet comes with the skin. Now, you may think this is silly to mention, but I’m guessing you’re keto. And, as a keto-er you need, need, need to make crispy salmon skin! Here’s how you do it: remove the skin from the salmon before cooking the filet. Heat avocado oil in a pan over medium-high heat. Salt the salmon skin and place in the hot oil. Cook on both sides, 3 minutes. Transfer to a plate to cool, and then chow down. It’ll be crispy and wonderful and deliciously tasty!

This entry was tagged: fish, ingredients, keto

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Hi! I'm Leanne (RHN FBCS)

a Functional Medicine Practitioner, host of the Healthful Pursuit Podcast, and best-selling author of The Keto Diet & Keto for Women. I want to live in a world where every woman has access to knowledge to better her health.

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