There are a number of reasons people practice a keto or low-carb, high-fat (LCHF) lifestyle. Often, they are looking to manage weight, control blood sugar and increase energy. To do this, these types of lifestyles focus on eating minimal carbohydrates to encourage the body to change its fuel source from glucose to fat.

When your body uses fat as an alternative fuel source, it’s known as being fat adapted (or keto adapted). As a metabolic state, it may help to curb cravings and aid feelings of satiation. Reaching ketosis–a similar metabolic state where your body makes ketones as an energy source–can also lead to fat adaptation.

Understanding keto adaptation, how to achieve it and its benefits can be helpful as you start or continue your low-carb lifestyle. Here’s how burning fat for fuel may enhance your healthy lifestyle.

What’s the Difference Between Sugar Adapted and Fat Adapted?

If you can be fat adapted, the opposite would be sugar adapted, or a sugar burner. Many people eating a standard American diet rely on carbohydrates for energy. This may cause the body to have more frequent drops in blood sugar and cravings for carbohydrate-rich foods.

As you eat more carbs, glucose levels rise. To help your body process excess glucose, the pancreas produces insulin, which facilitates the transfer of sugar into your cells.

People with type 2 diabetes either resist insulin’s effects or don’t make enough to regulate glucose levels. For some people, becoming fat adapted may help with blood sugar control, leading them away from sugar as a primary energy source and instead relying on fat.

What’s the Difference Between Ketosis and Fat Adapted?

The main difference between ketosis and fat adaptation has to do with the time it takes to achieve them. Ketosis can be reached in a relatively short amount of time. In fact, when you fast overnight or intermittently, your body can enter a form of ketosis where the liver begins making ketones. If you do not continue to either fast or eat a low-carb diet, ketosis isn’t sustainable.

Fat adaptation, or keto adaptation, occurs after a prolonged period of your body creating ketones. The result of fat adaptation is that you can eat and process carbs without falling out of ketosis, which may take a few weeks for your body to do. Once you reach this state, you may experience many of the benefits of a keto lifestyle like increased energy and healthy weight management.

Tips for Becoming Fat Adapted

Reaching a state of keto adaptation comes down to two basic factors: intermittent fasting and a low-carb diet. What does that look like? Here are a few tips for moving towards that state. (Always speak to your healthcare practitioner before substantially changing your diet.)

Eat Fewer Than 40 Carb Grams a Day

The number of carbs will vary depending on your goals and nutrition needs. For a strict keto diet, many people eat 20 grams of carbs or fewer per day. While this may accelerate your ability to enter ketosis, it doesn’t necessarily make you fat adapted faster.

Intermittent Fasting Can Be Done in Various Ratios

Fasting should be done in a way that serves your body best. For some, a 23:1 ratio, or one meal a day, keto diet is accessible, while others may need more than one meal a day. Other common ratios are 20:4 and 16:8, giving you more available hours to get your macros.

Keep Exercising

It’s important to stay active for both physical and mental health, but it also helps to burn glycogen stores. As you exercise, your body seeks out other forms of energy to burn.

Take a Keto Supplement

As you’re trying to boost your body’s ketone production to be fat adapted, it may be helpful to boost levels of beta hydroxybutyrate (BHB) with a keto BHB supplement. It may also help with appetite control.*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

What is the Keto Adaptation Timeline?

Keto adaptation essentially means that you are teaching your body to respond to fat differently, and that takes time. Here is a general breakdown of what the process may look and feel like.

Week One

Your body will still be searching for glucose as an energy source, even though you have cut carbs. You may feel what’s known as the “keto flu,” which is marked by brain fog, fatigue, irritability and lightheadedness. Not everyone experiences keto flu, and there are ways to curb it like getting proper macros and increasing electrolytes. During this first week, your body is increasing ketone production and will begin to burn more fat.

Week Two

You may still be feeling some of the early effects of less sugar, but typically, after a week to ten days, many people start to feel energized and fewer cravings.

Week Three

Typically, there will be no more signs of keto flu, and your body will start to officially become fat adapted.

Of course, your body will continue to change as it adjusts to your new lifestyle. Some people may experience a longer period of keto flu symptoms, while others may not feel it all.

Fat adaptation doesn’t have a set timeline, but if you remain committed to intermittent fasting and a LCHF lifestyle, you will likely start to feel the benefits more quickly. (Symptoms that persist may be signs of an unrelated condition and should be brought to your practitioner’s attention.)

Best Foods for Fat Adaption

Ever wondered which foods are best for reaching keto adaptation? Remember that the following suggestions should still fit within the macros you’ve calculated for your diet. Eating any one food in excess may affect your goals. Check out this list of keto-friendly foods that are sure to help the process while giving you optimal nutrition.

Meat and Fish

When it comes to meat, remember that keto is high fat, but not high protein. Excessive meat isn’t necessary to be fat adapted. Also, be sure to choose organic, preservative-free meats whenever possible. Here are some good meats to add into your diet:

• Chicken with skin
• New York strip steak
• Organ meats
• Ribeye
• Salmon
• Sugar-free bacon

Fruits and Vegetables

Most fruits, with the notable exception of berries, contain too much sugar to make them suitable for a keto diet.

• Avocado
• Blackberries
• Cabbage
• Cauliflower
• Kale
• Lettuce
• Olives
• Raspberries
• Spinach
• Zucchini

Fats

No, fat doesn't not automatically mean tons of bacon fat.

• Avocado oil
• Chia seeds
• Extra virgin olive oil
• Flaxseeds
• Ghee (clarified butter)
• MCT oil

6 Signs You’re Fat Adapted

There isn’t a test to determine if you are fat adapted, but there a number of signs that point to when you’ve reach it. Here are the top six signs to look for:

1. Fewer cravings. If you were a sugar burner who was always craving something sweet after a meal, you may notice those cravings decrease or even disappear.
2. Feeling full more quickly. Eating a higher-fat diet often results in feeling satiated more quickly, which may result in eating less food than you’re used to.
3. Increased energy. With fewer carbs, you may notice more sustained energy rather than highs and lows
4. Sleep quality. The combination of diet and intermittent fasting may improve your sleep quality with fewer disruptions. You may be able to fall asleep more easily and wake up feeling more refreshed.
5. Mental clarity. While the initial weeks of your low-carb lifestyle may be marked by feeling tired and foggy, when you are fat adapted, you will likely feel sharper.
6. Weight loss.: For many people, weight management is a goal of keto adaptation. If you notice steady weight loss after the first couple weeks of your new lifestyle, it’s a sign that you’re on the road to being fat adapted.