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The Bad Keto Fats: How to Spot and Avoid Them

If you’re new to keto or are considering making the transition, you may be wondering, are all fats okay to eat?

The simple answer is no.

While certain keto fats are great for keeping you energized, satiated and on track to achieving your weight loss goals, others are so damaging to your health no one should be consuming them — keto or not.

That’s why this guide will help you learn:

Before diving into the specific fats you’ll want to ditch from your ketogenic diet, you should know the difference between good keto fats and bad ones.
So let’s start there.

What Makes a Fat Unhealthy?

While a high-fat ketogenic diet does emphasize the importance of eating fats, there is a fine line here because not all fats are worth consuming.

And if you’re so laser-focused on increasing your fat intake that you lose sight of where your fat is coming from, you’ll see the complete opposite effect on your health.

So why are some fats bad for you?

It all comes down to how these fats are created and processed (hint: they don’t come from a whole food source).

#1: Bad Fats Start Out With Genetically-Modified Seeds

Most processed fats are made from the oils of specific plants such as soybean and corn.

However, many of these plants start out as seeds that have been altered, or genetically modified.

Soybean, corn and canola are all among the top GMO crops in the US[*]. So if you’re still using soybean or canola oil, you’re doing a massive disservice to your body.

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While there’s still more research that needs to be done, early studies have found that these altered seeds contain their own set of allergens your body is not used to processing[*].

So, for example, if you’re allergic to Brazil nuts and don’t realize the soybean oil you’re consuming in processed foods is from genetically modified soybeans and contains the same allergen gene found in Brazil nuts, you’ll unknowingly cause a similar reaction in your body.

And this could trigger an entire immune system attack, complete with flair ups and inflammation.

Another issue here is that consuming processed vegetable oils like soybean can also lead to other unwanted side effects.

In one study conducted on mice, researchers discovered a diet high in soybean oil led to increased rates of obesity and weight gain[*]. The mice also showed signs of insulin resistance and diabetes.

On the other hand, when the mice were fed a high-fat diet rich in healthy saturated fats like coconut oil, they did not see these same negative side effects.

The takeaway here is to choose fats from real, whole-food sources that haven’t been modified before they’ve even had a chance to sprout.

The next problem with these types of bad keto fats has to do with their shelf life.

#2: Processed Fats Were Made to Outlast the Apocalypse

If you remember your parents or grandparents stashing a can of vegetable shortening unrefrigerated in an unused upper cabinet of your kitchen, congratulations.

You know firsthand what a product from the manufactured trans-fat craze that started as early as the 1900s looks like.

Food manufacturers in those days designed these processed fats with three specific goals in mind:

  1. To extend the shelf life of their products for as long as possible.
  2. To keep these fats from going rancid without refrigeration.
  3. To create a fat that remained solid at room temperature.

But if a food was intentionally made to last this long on a shelf, what is it doing to your body?

According to the Food and Drug Administration (FDA), processed fats like partially hydrogenated oils fall under the murky category of “Generally Recognized as Safe” food items[*].

But then they also say eliminating these processed fats from people’s diets “could prevent thousands of heart attacks and deaths each year.”

So why exactly are processed and trans fats still accepted as safe if they could also be such a contributing factor in heart attacks and deaths?

Because trans fats are naturally found in trace amounts in keto foods like high-quality dairy products and red meat.

These sources of fat, such as grass-fed butter, are actually good for you and come loaded with incredible health benefits.

Thanks to this giant umbrella of trans fats that you can find in both real foods (like grass-fed meat) and fake food (like hydrogenated oils), the FDA can’t say all of them should be excluded from your diet.

But you should definitely stay away from any trans-fats that come from processed foods. Ditch the damaging fats from these oils and your heart, arterial walls and the rest of your body will be healthier.

And if you still need more convincing, this final issue is another reason why it’s time to say goodbye to these terrible fats on a keto diet.

#3: The Processing Treatment is Even Worse for Your Health

On top of using GMO seeds, pre-processed fat is further treated with harsh and toxic chemicals, such as bleach and hexane, as it’s being manufactured.

Food manufacturers also use a high heat process made to kill bacteria and other harmful pathogens, but what ends up happening is much more dangerous.

When fat becomes oxidized with this heat, free radicals are created. Free radicals in processed fats can damage healthy cells.

Processed fats like these are also loaded with omega-6 fatty acids.

These fatty acids are not inherently bad, but your body requires the right balance of omega-6 fatty acids to omega-3 fatty acids to be healthy, and when you consume foods too high on omega-6s, you can experience chronic inflammation.

This inflammation can lead to an increased risk for developing:

  • Certain cancers, including breast cancer
  • Heart disease and heart attacks
  • Obesity
  • Depression

You’re not doing your health any favors by consuming bad fats. So to completely eliminate this processed junk from your diet, you have to know where these bad fats are hiding.

Bad Keto Fats: Remove These From Your Diet

When polyunsaturated fats are processed (such as canola oil), artificial trans fats are created.

These are the deadly trans fats you want to banish from your low carb, high-fat ketogenic diet.

If you have trouble reading labels to pick out these bad fats, you’re not the only one. Manufacturers purposefully make it tricky to separate simple ingredients from processed junk.

To help you decipher every label you come across, avoid the following ingredients when you see them on a label:

#1: Hydrogenated or Partially Hydrogenated Vegetable Oils

Hydrogenated and partially hydrogenated oils are the easiest ones to spot on a nutrition label since they’re now required to be labeled as such.

These two fats are commonly found in processed foods you’ve probably already eliminated from your keto diet, such as:

  • Margarine
  • Crisco
  • Cookies
  • Crackers
  • Breads
  • Non-dairy creamers
  • Popcorn
  • Frosting
  • Tortilla chips
  • Ketchup

Trans fats like these can also hide in carb-heavy items like burger buns, taco shells, frozen pizza dough and those pop and bake cans of cinnabuns and biscuits too.

Since these items are off-limits on keto anyway, you’re better off making your own versions using keto recipes to avoid these harmful fats (and all the carbs).

But the next sneaky fats aren’t so easy to stay away from:

#2: Processed Oils, Including Ones Which Have Been Heated

When you’re scanning nutrition labels at the grocery store, you may find almonds roasted with salt and some seemingly healthy oil, for example, and think you’re in the clear if the macros work out right.

But even though these oils sound like they come from a natural source, they’re often just low-quality, inflammatory oils, such as:

  • Peanut oil
  • Sunflower oil
  • Safflower oil
  • Grapeseed oil
  • Palm oil
  • Corn oil
  • Soybean oil

Just because the macros on that package may be keto-safe, it doesn’t mean you’ll be any healthier consuming what’s inside.

To ensure you’re truly healthy on keto, steer clear of any foods that mention those oils on their label.

Using our example, you could roast your own almonds using a healthier oil that can withstand the heat without breaking down, such as avocado or coconut oil, and sprinkle on a healthier salt like Himalayan pink salt afterwards.

But you also have to think about the oil from fried foods too.

You may think it’s just the breading you have to worry about when it comes to deep fried foods on keto, but these are also cooked in subpar oils like canola and peanut.

Foods cooked in these oils can damage your overall health.

Even if there’s a keto-friendly food underneath your keto-safe breading, such as zucchini, calamari or even an unbreaded chicken wing, it’s still an unhealthy food if you fry it in unhealthy oils.

Harmful Trans Fats are Found in Foods 768x384

If your goal is to lose weight and improve your health, these oils have no place in your keto meals.

With all this talk about healthy vs unhealthy keto fats, you’re probably ready to ask this next common question:

What About Saturated Fats?

You may be surprised to see saturated fats missing from this list of fats to avoid on a ketogenic diet — and that’s for good reason.

As you can learn more about in this podcast episode with Nina Teicholz, healthy saturated fats are not the problem.

In fact, saturated fats from healthy sources like avocado, grass-fed butter and coconut oil can be a great addition to your low carb keto meal plans, along with these other sources of healthy fats.

Good Keto Fats: Reach for These Fat Options Instead

You can see a full list of good fats to enjoy on a ketogenic diet in this guide.

In the meantime, here’s a mini cheatsheet of all the better-for-you fats you should include in your ketogenic meals:

Many of these choices are loaded with unprocessed polyunsaturated fats and monounsaturated fats which can help you:

  • Lose weight
  • Improve your energy levels
  • Fortify your gut health
  • Keep cancers and heart disease at bay
  • Improve insulin resistance and insulin sensitivity
  • Reduce blood pressure levels

You’ll also find those same health perks in nuts and seeds since these both contain high amounts of healthy fats and low carb counts.

The best keto nuts and seeds include:

  • Macadamia nuts
  • Pecans
  • Brazil nuts
  • Hazelnuts
  • Walnuts
  • Chia seeds
  • Hemp seeds
  • Flax seeds

But, as mentioned in this guide, some nuts do have higher net carbs than others so it’s best to understand which low carb options are better for you on a keto diet so you can reach and maintain ketosis with ease.

You can also sneak in a few of these healthy fats simultaneously by making keto fat bombs. These portable, portionable treats are the perfect addition to your keto snack or dessert routine.

For a better idea of what to eat on a keto diet, check out this guide: Keto Diet Foods: The Full Ketogenic Diet Food List later.

Your Next Move After Learning the Truth About Keto Fats

With this information under your belt, you’ll be less tempted to buy or snack on anything containing one of the harmful fats mentioned in this guide.

By doing this, you’ll help your body maintain ketosis and keep your health in tip-top shape for the long-term.

For more keto-friendly substitutes that don’t come with a host of dangerous ingredients and unwanted side effects, check out these low carb recipes too.

On keto, it’s not just about reaching ketosis. It’s about making choices that help you become as healthy as you want to be.

By avoiding these harmful fats and loading up on better-for-you ones, you can do just that and look good at the same time.


One thought on “The Bad Keto Fats: How to Spot and Avoid Them

  1. I had no idea, until recently, that vegetable oils were poison. I’ve spent most of my life so far, thinking that I was doing my body good by staying away from all the “bad” fats. Thank you Dr. Gustin for your recent podcast and this blog! I’m spreading the word and hoping that the restaurant industry will someday catch on. You’re making such a huge difference. Keep up the amazing work!

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