Eating Keto means eating most of your calories from fat.
This scares some people. Isn’t fat bad for you? Doesn’t it clog your arteries?
That’s what we’ve been conditioned to believe. Saturated fat, in particular, has been demonized for decades on the back of 1950s population research. [*]
This research has largely been debunked, but the anti-fat sentiment persists. Even today, otherwise reputable organizations like the American Heart Association (AHA) continue to get the fat story wrong. [*]
This can all be rather confusing. You know Keto is high-fat, but what types of fat should you eat to promote good health? And how can you ensure you’re getting enough fat to hit your Keto macros?
Keep reading. This article has you covered.
Why Keto Is High-Fat
When you eat a Keto diet, you consume about 60-70% of your calories from fat, 25-30% from protein, and 5-10% from carbohydrates.[*]
Fat is mostly a placeholder on Keto—a macronutrient that provides energy in the absence of carbs. Some explanation will help.
The key to ketosis (aka, burning fat on Keto) is carb restriction. By keeping carbs low, you keep blood sugar and insulin levels low. This sends a memo to your liver, which soon gets busy burning fat and making ketones.
So carbs are out. That leaves protein and fat.
Protein is super important for muscle and brain health, but its benefits are confined to a fairly tight window. If you ate all your calories from protein, you wouldn’t necessarily gain more muscle, and you’d probably overburden your kidneys.[*]
An excess of protein also spikes insulin levels, which would spell an end to fat-burning ketosis. [*]
And so the bulk of your Keto calories must come from fat. Dietary fat has a minuscule impact on insulin levels, helping you stay in fat-burning mode.
On Keto, fat is your fuel.
Different Types of Fat: Which Are Healthy?
When you eat fat, you’re eating molecules called triglycerides. When digested, these molecules split into compounds called fatty acids to be burned for energy or stored for later.
Fatty acids come in four varieties: saturated fat, monounsaturated fat, polyunsaturated fat, and trans fat. Let’s talk more about these four, and see which belong on your healthy Keto diet.
#1: Saturated Fat
“Saturated” with hydrogen bonds, saturated fat is found in meat, lard, egg yolks, coconut oil, butter, and palm oil.
Saturated fat has a bad rep. It started back in the 1950s when a doctor named Ancel Keys published data linking lower sat fat consumption to lower rates of heart disease. [*] His shining example of a healthy, low-fat population? Italy.
But as the saying goes, correlation doesn’t prove causation. Could it be that Italians were healthy for some other reason? Sunlight and laughter maybe?
Fast forward to today and the data doesn’t look good for Keys’ theory. For example, two massive meta-analyses—after analyzing nearly 1 million people—found zero links between saturated fat consumption and heart disease. No link! [*], [*]
The truth is, there’s a lot to like about saturated fat. Unlike polyunsaturated fat, saturated fat is a stable fat—ideal for high-heat cooking.
Also, some of the healthiest foods on the planet are high in saturated fat. Egg yolks, for instance, are excellent sources of essential nutrients like choline, iron, and vitamin A.
Verdict? Saturated fat is definitely Keto-approved.
#2: Monounsaturated Fat
Found in olives and avocados, monounsaturated fat isn’t controversial. When you look at the literature, higher intakes are linked to lower blood pressure, healthier blood sugar levels, and a variety of other health improvements. [*]
Verdict? Don’t skimp on monounsaturated fat.
#3: Polyunsaturated Fat (PUFA)
Polyunsaturated fat (PUFA) is controversial. A little background will help.
There are 2 categories of PUFAs; Omega-6s and Omega-3s.
Back in the 1970s, the food industry started promoting high-PUFA vegetable oils as healthy based on research suggesting that replacing saturated fat with PUFAs lowered bad cholesterol. Saturated fat bad, polyunsaturated fat good. That was the message.
The celebrated high-PUFA vegetable oils included soybean oil, sunflower oil, safflower oil, cottonseed oil, and peanut oil—all of which are omega-6 oils, and they became staples of the American diet. Even today, the AHA maintains that veggie oils are heart-healthy.[*]
On the other hand, Omega-3 oils (flax seeds, fish) help resolve inflammation, and can be beneficial for autoimmune diseases, promoting weight loss, and disease prevention.[*]
Bottom line: you do need both, but in the right balance!
Another noteworthy concern is that vegetable oils are prone to oxidation, especially when exposed to high heat - and many of the Omega-6 vegetable oils consumed in a standard American diet are from deep-fried foods, making them especially unhealthy. Consuming these oxidized oils increases inflammation and all the conditions related to inflammation noted above.[*]
If cooking with these oils yourself, make sure you are only doing so at low to moderate heat. Each oil has a “smoke point” at which the oil becomes oxidized, or rancid.
It’s a good idea to be aware of the smoke point of any oil you are using and cook within the appropriate temperature range, but particularly with PUFA veggie oils. It’s also helpful to be aware of what rancid oil smells like, as these PUFA oils are particularly prone to spoiling or going “rancid” with age.
If you are not familiar with this smell, cook a veggie oil or olive oil at high heat and notice how the smell changes. If you’ve ever eaten a nut or seed that tasted “off,” that’s a good example of what rancid oils smell like. Yuck.
Overall, we recommend you avoid using Omega-6 veggie oils. The best way to meet that 4:1 or less ratio is to use more Omega-3 oils (flax, chia, hemp) and MUFAs (olive oil, avocado oil), while eating more fatty fish, walnuts, chia seeds, hemp seeds, and flax seeds.[*]
Verdict? Limit omega-6 oils and eat fatty fish for omega-3s.
#4: Trans Fat
Trans fats are vegetable oils that have been engineered, via hydrogenation, to be more shelf-stable. Longer shelf life, higher profits for manufacturers.
You probably know that trans fats are bad for you. They’ve been linked to pretty much every disease in the book, from heart disease to Alzheimer’s to cancer. [*]
Trans fats are so bad that the World Health Organization has recommended they be removed from the global food supply. [*] In America, the FDA has banned trans fats as of 2018, but extensions have allowed them to linger in processed foods until 2021.
Avoid trans fats by reading food labels closely. Anything with “hydrogenated” or “partially hydrogenated” in the name is a trans fat.
Verdict? Steer clear of trans fats!
How To Eat Enough Healthy Fat On Keto
Eating 60-70% of your calories from fat can seem daunting, especially if you’re new to low-carb living. Should I be chugging olive oil straight from the bottle?
Hey, if that works for you, go for it. But here are some easier ways to ensure you’re getting enough fat to hit your Keto macros:
- Eat eggs. Eggs are the perfect Keto food—about 65% fat, 35% protein, minimal carbs, and highly nutrient-dense.
- Favor fatty cuts of meat. Ribeye, chuck roast, and lamb leg are solid Keto-friendly cuts. Don’t slice off the fat!
- Veggies as a fat vehicle. Cook low-carb veggies in coconut oil or butter—and use generous portions of olive oil as a salad dressing. As a bonus, you’ll absorb more vitamins (like A, D, K, and E) with fat around.
- Take MCT oil. MCT oil is a coconut-derived fat that heads straight to your liver for ketone production. Start slow with this one (1 teaspoon at a time), as larger amounts can have a laxative effect.
- Make fat bombs. Mmm…fat bombs. Hard to believe they’re even Keto. Whip up these Keto Coconut-choc Fat Bombs and Keto Buckeye Fat Bombs, straight from the Carb Manager kitchen.
One Last Tip
One last tip. And it’s the most important.
It’s the only way to truly know if you’re getting enough fat on Keto.
The tip? Use a macro tracker! Just log your meals, let the AI look up the nutrition info, and out pops your daily fat intake.