Full Answer
- Diet Doctor How long does it take to become fat adapted? How long does it take for your body to get through the fat-adaptation phase, so that you can start running on ketones and reap all its benefits? Here’s an excellent and concise explanation by Dr. David Ludwig – the answer seems to be at least a couple of weeks:
Fat adaptation is your body’s ability to burn fat as its main fuel source. When you’re fat-adapted, you turn fat into adenosine triphosphate (ATP), the energetic currency that powers nearly every cell in your body. Early humans were fat-adapted.
Once you’re fat-adapted, your metabolism favors burning adipose tissue (body fat) for fuel whenever it needs energy — provided you aren’t overeating, which is hard to do on a keto diet because it’s so satiating. Bottom line: If you’re losing weight after about a month of a low-carb dieting, you’re probably fat-adapted.
If you’ve been following keto for a few weeks and want to know if you’ve become fat adapted, here are the top seven signs to look for: Fat adaptation influences your hunger hormones. Ghrelin, the main hunger hormone, is decreased when you’re fat adapted. This makes you want to eat less often and stop craving snacks between meals.
Theoretically, once you reach a fat-adapted state, you can introduce carbs into your diet for short periods of 7–14 days — which allows your body to easily burn fat for energy once you return to a ketogenic diet. However, most of this effect is limited to speculation or anecdotal reports.
To speed up your fat-adaptation, eat less carbs and more fat, try fasting, and exercise regularly. When you start losing fat mass, craving less carbs, and feeling more stable energy throughout the day—you'll know it's working.
7 Common Signs That You're Fat AdaptedDecreased cravings between meals (2) Fat adaptation influences your hunger hormones. ... Increased energy. High-carb diets can make you tired. ... Feeling satiated with less food. ... Heightened mental acuity. ... Increased fat loss (5) ... Better sleep (6) ... Increased endurance with physical activity.
How Long Does It Take to Reach Fat Adaptation? It generally takes from 30 days to 12 weeks of sticking to a keto diet to become fat adapted. During this time you want to focus on clean whole foods and stick to eating a ketogenic diet without cheats or deviations.
But did you know you can get better results from your diet and workouts by changing how your metabolism works? Fat adaptation refers to a shift in your metabolism that automatically leads to higher fitness levels, lowers your long-term risk of disease, and even makes fat loss faster and easier[*][*][*].
To become fat- or keto-adapted, eat a low-carb, high-fat diet aiming for a carb intake between 20-50 grams per day. This will help you transition from burning glucose (being a sugar burner) to burning fat stores (being a fat burner).
Your muscles first burn through stored glycogen for energy. “After about 30 to 60 minutes of aerobic exercise, your body starts burning mainly fat,” says Dr. Burguera.
Traveling for work or vacation, eating an unplanned meal, going through a major life transition during which well-meaning loved ones shower us with meals, or simply having a weekly cheat day can all cause us to fall out. While no specific foods can cause us to be kicked out of fat burn, consuming too many carbs will.
Once you're fat-adapted, your metabolism favors burning adipose tissue (body fat) for fuel whenever it needs energy — provided you aren't overeating, which is hard to do on a keto diet because it's so satiating. Bottom line: If you're losing weight after about a month of a low-carb dieting, you're probably fat-adapted.
The time it takes to enter ketosis varies from person to person ( 6 , 7 ). In general, it can take 2–4 days if you eat 20–50 grams of carbs per day. However, some people may find it takes a week or longer to reach this state ( 6 , 7 , 8 ).
Fat adaptation may start any time between 4 and 12 weeks after you enter ketosis, depending on the individual and how strictly you adhere to the keto diet. Notably, endurance athletes may adapt even sooner ( 5. ). Fat adaptation is thought to be a long-term metabolic transition to burning fat instead of carbs.
What does ‘fat adapted’ mean? The keto diet is based on the principle that your body can burn fat instead of carbs (glucose) for energy. After a few days, a diet very low in carbs and high in fat puts your body in ketosis, a state in which it breaks down fatty acids to form ketone bodies for energy ( 1 ). “Fat adapted” means that your body has ...
Fat adaptation is a long-term metabolic adaptation to ketosis, a state in which your body more efficiently metabolizes fat as its main energy source.
Theoretically, once you reach a fat-adapted state, you can introduce carbs into your diet for short periods of 7–14 days — which allows your body to easily burn fat for energy once you return to a ketogenic diet. However, most of this effect is limited to speculation or anecdotal reports.
This initial keto phase, which allowed only 600–800 calories per day, continued until each participant lost a target amount of weight. Peak ketosis lasted 60–90 days, after which the participants were placed on diets that incorporated balanced macronutrient ratios ( 13. Trusted Source. , 14.
Among keto adherents, burning carbs for energy is known as “carb adapted.”. Most people following non-keto diets could be considered carb-adapted, although their bodies use a mixture of carbs and fats. The ketogenic diet shifts this balance to favor fat burning.
). In comparison, fat adaptation is a longer-term state of ketosis in which you consistently derive most of your energy from fat given your changes in diet. This state is believed to be more stable, as your body has transitioned to using fat as its main energy source.
To become fat- or keto-adapted, eat a low-carb, high-fat diet aiming for a carb intake between 20-50 grams per day. This will help you transition from burning glucose (being a sugar burner) to burning fat stores (being a fat burner). You can be in a fat adapted state without being in ketosis (keto adapted), and vise versa.
Fat adaptation means you’re burning fat through fat oxidation [ * ]. A ketogenic diet — which means eating a mostly fat-based diet comprised of animal fats and high-quality protein — puts your body in a state of ketosis. In ketosis, your body produces ketone bodies for energy in an attempt to use up fatty acids.
Monitor your intake of high-quality protein. By reducing your carb intake, your body will burn off all your remaining carbs and glycogen stores right away. Then it will tap into your excess fat stores to give your metabolism and energy a boost.
Your body is capable of metabolic flexibility, or switching between using sugar or adipose tissue (aka stored fat), to perform all its daily functions. To get to the metabolic state of fat adaptation, you need to tackle three steps: Limit the number of carbs you eat. Eat a larger portion of healthy fats. Monitor your intake of high-quality protein. ...
Consequently, your insulin levels rise. When your insulin levels stay elevated, this is known as insulin resistance, which can lead to type 2 diabetes [ * ]. With too much insulin floating around in your bloodstream, your brain’s chemical signals are all thrown off, including those that let you know you’re full.
This phase might include the keto flu, which can last anywhere from 3-14 days. During this first week or two, your body is using up stored glucose, or glycogen, and is signaling you to replace them [ * ]. From there, you’ll shift into the second phase, which can last between 6-8 weeks.
Your body works overtime to combat this surge of glucose by sending out more insulin, a hormone to help sugar get out of your bloodstream and into your cells. Consequently, your insulin levels rise.
Plainly put, “fat adapted” is the metabolic state your body is in once you’ve been in ketosis long enough that your body has efficiently transitioned from burning carbs/sugar for energy to burning fats from your food, body-generated fats, and your stored body-fat reserves for energy.
It generally takes from 30 days to 12 weeks of sticking to a keto diet to become fat adapted. During this time you want to focus on clean whole foods and stick to eating a ketogenic diet without cheats or deviations.
To tell if you’re fat-adapted: check your energy levels, cravings, focus, endurance performance, and body fat. If they’re all improving, good news: you’re burning fat full-time.
Fat is your body’s best way to save energy. It’s compact (especially compared to sugar storage) and it’s easy to put on, as most of us know all too well. It also burns hot, producing a lot of energy as you work through it. Unfortunately, a modern, high-carb Western diet does not promote fat-adaptation.
You’ll start making ketones in the first week of keto. The fat adaptation process, however, may take a month or more. That’s why it’s important to stick to strict keto for at least a few weeks when you’re just starting out if you want all the biggest benefits of ketosis.
The idea is that when you eat low-carb long enough, you’ll start burning fat (rather than sugar) for energy.
The good news is that you don’t need a ketone meter, blood test, or urine sample to tell if you’re fat-adapted. There are clues, both mental and physical, that signal your level of fat-adaptation. This article will cover how to know whether you’re fat-adapted, as well as the difference between being fat-adapted and simply being in ketosis.
The average person may enter a mild state of ketosis during an overnight fast. Fasting causes your blood sugar and insulin levels to drop. These metabolic changes signal your liver to turn fatty acids into ketones [ * ].
According to keto expert and New York Times best-selling author, Dr. David Ludwig, it can take two to three weeks or longer to become fully fat adapted depending on your bio-individuality and how strictly you adhere to a low-carb, moderate-protein, higher fat diet. (Go overboard on your grams of carbs per your specific ideal daily macronutrients ...
When you’re fat adapted, you are on a fat-burning diet and have stable energy levels throughout the day, which means you experience more energy and less fatigue.
One amazing sign you’re fat adapted is you’ll start sleeping better and waking up feeling more rested. Studies show that the deep phase of sleep, called phase four, is lengthened on keto. Researchers theorize that this might be due to the affect keto has on adenosine in your brain. Adenosine promotes this deeper slow-wave sleep.
Fat adaptation influences your hunger hormones. Ghrelin, the main hunger hormone, is decreased when you’re fat adapted. This makes you want to eat less often and stop craving snacks between meals.
When your body gets the nutrients it needs from fat, you feel more satiated with less food. Another reason you feel full with less food? Ketones also boost cholecystokinin, a hormone that keeps you feeling full.
Ketosis and fat adaptation are not the same. When you fast, embark on intermittent fasting, or cut way down on your carb intake for an extended period of time, your blood sugar and insulin levels drop. (1) With an absence of carbs (sugar) to rely on for energy, your body, instead, reaches for fat and converts it to ketones to use as its fuel source. This is known as ketosis.
But by the time you’re fat adapted, your liver is used to converting fat into blood ketones for fuel. Increased fat intake lowers insulin levels. Insulin is a hormone that tells your body to store fat, so with less insulin, less fat gets stored. This means you continue to lose fat!
Being fat adapted makes it easier to burn stored body fat for energy. Fat adaptation gives access to an unlimited amount of energy in the form of adipose tissue. Fat-adapted people can cover up to twice as much of their energy needs from fat[ii][iii]. This decreases dependency on carbohydrates and eating.
Fasting is the best way to promote fat adaptation and it makes the body more energy sufficient. Reduce Your Carbohydrate Intake – To maintain fat adaptation you should reduce your carbohydrate intake or at least time-restrict it. The lower your carbs, the more keto adapted you can become. On non-ketogenic diets, ...
Intermittent fasting speeds up fat adaptation because while fasting you’re forced to sustain your metabolic processes with your body fat stores. The longer you fast and the smaller your eating window, the more carbs you can get away with but too many carbs will still lock you into the glucose-dependent state.
You can gain the benefits of glucose on a fat burning metabolism but you can’t immediately start burning ketones if you haven’t gone through the adaptation process.
Athletes who’ve keto-adapted over the course of 6-36 months can even burn fatty acids and ketones at 90% of their VO2 max [iv]. MCT Oil and Ketones – Medium-Chain Tryglycerides can be transported into the mitochondria faster than glucose or regular fatty acids, which enables them to be used immediately for energy.
Every person is fat adapted to a certain degree but most people’s fat adaptation is very poor because of high eating frequency, processed foods, and high amounts of carbohydrates in the diet. This will keep the body locked in a glucose burning metabolism. Keto adaptation and fat adaptation describe the same thing but they differ in terms of degree.
Here are the symptoms of fat adaptation to look out for: 1 More energy when not eating 2 Reduced inflammation and faster recovery 3 Increased endurance 4 No sugar cravings or hunger 5 Improved mental clarity and brain power 6 Stable energy levels throughout the day 7 No symptoms of hypoglycemia when blood sugar gets lower 8 Higher acetone in the breath or ketones in blood 9 You can go for an entire day without eating or feeling tired
After two to four weeks of exercising regularly, improvements in strength and fitness will start to be noticeable.
Much depends on whether you have been maintaining a caloric deficit, which is needed to produce weight loss. After four weeks or more of regular exercise, you may be able to see improvement in your physical health, as well as in other areas of your life, such as productivity, less sick days and improved mood.
Any physiological responses to exercise will occur both immediately and over the long term if you keep up your exercise habit. Adaptations occur in your muscles, cardiovascular system, hormones and metabolism. When you are exercising, moving and generating force with your body, your skeletal muscle fibers go to work.
The physiological adaptations that your body undergoes when you exercise help protect you against chronic diseases such as cancer, high blood pressure, diabetes and heart disease. Your body systems undergo both immediate and long-term adaptations in response to exercise.
Skeletal muscle force can be generated when your muscles remain static (isometric) — when the weight that you are using is causing an external resistance that is equal to the force produced by your muscles. A great example of this is when you are holding a heavy box and resisting dropping it.
Advertisement. There are two ways that the human body adapts to exercise: acute physiological response and chronic physiological response. Acute responses refer to changes in the body systems in reaction to exercise that occur immediately, such as an increase in heart rate. Long term adaptation to exercise is a chronic response ...
Advertisement. In turn, if you stop your training, then you will lose this efficiency that you garnered while exercising. This loss of adaptations is called detraining.