How Much Fat Do I Need to Eat on a Keto Diet?

Ask Theresa is a weekly advice column by Theresa Link. A Virta Health Coach since 2015 and a loyal follower of the ketogenic lifestyle, Theresa is a Registered Dietitian who is an expert in living a metabolically-healthy life. 

In this week’s column, Theresa talks fat: the luscious, rich, wholesome nutrient that illuminates our skin and nourishes our bodies. The amount and type of fat you should eat depends on 3 different scenarios. If you’re in ketosis and have weight to lose, you should add fat to satiety, but not to excess. If you’re in ketosis and you don’t have weight to lose, you should add enough to maintain your weight. If you’re increasing your carb target a bit, you may need to lower your fat intake. Read on for more tips.

‍❓Question:‍

Theresa,

I’m in my second week of Virta and I’ve got a question: how much fat do I REALLY need to eat? I know the recommendation is to eat until I’m satisfied, but honestly I’ve never really known what satiety feels like. Should I be putting butter in my coffee? Eat a bunch of fat bombs every day? Do I need to add cream cheese and mayo to absolutely everything? If I eat more fat, will I lose more weight? Help!

Sincerely,

Flustered over Fat

👩🏻💻 Theresa:‍

Dear Flustered,

Starting a well-formulated ketogenic diet can be really exciting. You get to eat all the things you’ve likely been told to avoid for years! Have you heard that little voice in your head say, wait – I can have bacon, chicken skin, cheese, sour cream, steak, butter, olive oil, eggs, and heavy cream? Seriously?

Indeed, that little voice inside your head is thrilled, but maybe also a bit unsure. You’ve likely been told that eating fat makes you gain weight, but you’ve also heard that if you’re in ketosis, the more fat you eat, the better.

Well, neither of these ideas is completely right. The truth is somewhere in the middle. How much fat you really need to eat can be boiled down to 3 scenarios: if you have weight to lose, if you don’t have weight to lose, and/or if you’re increasing your carb target. Keep reading to find out more.

‍Scenario 1: You Have Weight To Lose‍

First, let’s review fuel partitioning. This describes how your body uses different types of fuel: carbs (glucose) or fat (ketones). When you limit carb intake below your carbohydrate tolerance, your body will then start burning fat for fuel. This can be both fat within your body and external sources of fat. 

When we refer to a well formulated ketogenic diet that’s low in carbs and high in fat,  low-carb, high-fat, the “high in fat” part includes both the fat you eat and the fat stored in your body. The more fat you eat, the less of your own fat you’ll burn. That’s why we suggest eating enough fat to feel satisfied, or comfortable until your next meal without feeling starved or stuffed.

In a nutshell, if you want to lose weight, you need to use your own fat stores. If you didn’t get much fat at lunch, consider having a decaf coffee with a tablespoon of heavy cream. But don’t overdo it with extra fat just for fun, as that can hinder your weight loss. Try adding 1-2 tablespoons of fat per meal from sources like butter, cooking oils, heavy cream, or sour cream if your meal was light on fat. If you’re still hungry at dinner, add a bit more. Monitor your weight and work with your coach to find your sweet spot.

‍Scenario 2: You Don’t Have Weight To Lose (Or You Are Maintaining Your Weight Loss)‍

If you’re in ketosis and don’t have much weight to lose, or if you’ve reached your weight goal and want to maintain it, ensure you’re getting enough fat in your meals in order to meet your body’s energy needs since you won’t be providing much from your own fat stores.

Add an extra pat of butter to your chicken thighs, pesto sauce on your salmon, or chimichurri on your steak. Use veggies as a vehicle for fat by sautéing in butter or cooking oil, topping with cheese, or dipping in lemon aioli. Fresh whipped cream with your berries? Go for it!

‍Scenario 3: You’re moderately increasing your carb intake‍

Some folks might be experimenting with increasing their carbohydrate intake to find their sustainable sweet spot. Maintaining a lower-carb lifestyle is still a priority, but maybe getting your ketones to 1.5 isn’t. That’s ok!

However, this approach adds a layer of complexity. The more carbs you eat, the lower your fat intake should be to balance energy requirements. Additionally, if you increase your carbs enough, we’d suggest you focus more on unsaturated fats like olive oil, avocado oil, oils from fatty fish like salmon, nuts, seeds, and avocados. The health impact of eating a higher carb diet with a higher amount of saturated fat (fatty meats, cheese, sour cream, bacon) is not entirely clear. For that reason, if you’re not in ketosis, we recommend limiting your intake of saturated fat and focusing more on the unsaturated oils mentioned above.

As you can probably imagine, this scenario is like being on a teeter totter. As one side goes up, the other side comes down. Exactly how far up and how far down is right for you is a conversation between you and your coach. 

The Takeaway

Remember that your own body fat stores supply energy, so if you have weight to lose, you don’t need to add quite as much fat as someone who is already at their goal weight (or is looking to gain weight). If you’re increasing your carbs a bit to achieve a more sustainable lifestyle, you’ll need to decrease your fat intake a bit and balance out your saturated fat intake with more monounsaturated fats. When in doubt, lean on your care team for specific guidance.

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