How Long Does It Take to Lose Weight in Ketosis?

Medically Reviewed on 4/26/2022
How Long Does It Take to Lose Weight in Ketosis
It can take 2-4 days or longer to start losing weight in ketosis, although the rate of weight loss depends on your metabolism and fitness level

Ketosis is a metabolic state in which the body uses fat as fuel instead of carbs. According to proponents of the keto diet, ketosis is key to quick weight loss. It can take 2-4 days or longer to start losing weight in ketosis, although the rate of weight loss depends on various factors such as your metabolism, carb-protein-fat intake, fitness level, and how strictly you follow the diet.

Although you may start to lose weight quickly in the beginning, the initial weight loss is water weight. After 1-2 weeks, weight loss slows as your body adjusts to the keto diet. You should avoid trying to lose more than 2 pounds a week, as losing weight rapidly can lead to dehydration, mood swings, irritability, weakness, and fatigue.

How to achieve ketosis

During ketosis, ketone levels increase in the blood. With healthy ketosis, ketone levels should be in a range of 0.5-3 mg/dL. If ketone levels are too high, you may be dehydrated and jittery. 

Fasting is the quickest way to achieve ketosis. However, this will work only for a few days and is not ideal because you are not getting enough important nutrients. The best way to achieve ketosis is to go on a low-carb diet or follow a ketogenic (keto) diet, which is a low-carb high-fat diet that restricts your carb intake to fewer than 50 grams per day to as little as 20 grams per day. The level of carbohydrates to induce ketosis varies from person to person. 

A combination of the keto diet and regular exercise can help you achieve a faster rate of weight loss.

How does your body lose weight in ketosis?

Ketosis occurs when your body does not have enough sugars to burn for energy, so it burns fats instead, leading to weight loss. This is the principle behind the keto diet. 

Normally, your body uses carbohydrates from the food you eat or from glycogen (carbs stored in the liver) as a preferred source of energy. When you eat fewer carbs, your body cannot make glycogen and thus turns to fats to use for energy. Your liver breaks down fats into substances called ketones, which are byproducts of fat metabolism. Glucose is the main source of energy for your brain. Therefore, when you follow a low-carb diet, a larger portion of your brain will use ketones for energy as well.

The high-fat content of the keto diet makes you feel full throughout the day, helping you cut down on your overall eating. In the long term, a ketogenic diet suppresses your appetite, which causes you to consume fewer calories.

While you adapt to the keto diet, you may experience nausea, fatigue, dizziness, bad breath, and other side effects. Drink plenty of water to ease or keep some of these symptoms at bay. You should avoid keto diets if you have conditions such as diabetes mellitus or advanced heart disease and if you take insulin or diabetes medications.

Can you take keto supplements to enter ketosis?

If you are unable to enter or maintain ketosis, you can take keto supplements that contain ketone salts and ketone esters. These are available in the form of pills, powders, and drinks

However, if you are not an athlete, these supplements should be taken under medical supervision. Athletes and bodybuilders can benefit from keto supplements because they perform high-intensity activities that require more energy. But in nonathletic or people who don’t exercise as much, ketogenic supplements can lead to ketoacidosis, which is a life-threatening condition.

If your goal is to lose weight, consult a certified nutritionist who can guide you through your weight loss journey and ensure that you are shedding pounds safely.


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Medically Reviewed on 4/26/2022
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