The ketogenic diet is a fantastic way to improve health and lose weight. Follow the keto diet correctly, and this low-carb, high-fat diet can raise ketone levels. Ketones provide fuel for a body’s cells and lots of health benefits. When a body reaches ketosis, it changes, and insulin levels drop, and fat gets broken down. The liver produces many ketones that provide brain energy. For more information about ketosis and how it works, check out the Body Reboot book and keep reading! We also discuss how to know if a body has reached ketosis.
Medical News Today provides some quick facts on how ketosis works:
Ketosis occurs when the body does not have sufficient access to its primary fuel source, glucose.
Ketosis describes a condition where fat stores are broken down to produce energy, which also produces ketones, a type of acid.
As ketone levels rise, the acidity of the blood also increases, leading to ketoacidosis, a serious condition that can prove fatal.
People with type 1 diabetes are more likely to develop ketoacidosis, for which emergency medical treatment is required to avoid or treat diabetic coma.
Some people follow a ketogenic (low-carb) diet to try to lose weight by forcing the body to burn fat stores.
Medical News Today explains more about ketosis and how the body typically uses ketones on a high carb diet. When you go on a high-fat diet, the body uses fat as an alternative fuel source which helps many people lose weight.
In normal circumstances, the body's cells use glucose as their primary form of energy. Glucose is typically derived from dietary carbohydrates, including:
sugar – such as fruits and milk or yogurt
starchy foods – such as bread and pasta
The body breaks these down into simple sugars. Glucose can either be used to fuel the body or be stored in the liver and muscles as glycogen.
If there is not enough glucose available to meet energy demands, the body will adopt an alternative strategy in order to meet those needs. Specifically, the body begins to break down fat stores to provide glucose from triglycerides.
Ketones are a by-product of this process.
Ketones are acids that build up in the blood and are eliminated in urine. In small amounts, they serve to indicate that the body is breaking down fat, but high levels of ketones can poison the body, leading to a process called ketoacidosis.
Ketosis describes the metabolic state whereby the body converts fat stores into energy, releasing ketones in the process.
If you’re familiar with intermittent fasting, then you know that it can help you lose weight. When you implement intermittent fasting on the keto diet, Dr. Axe explains how it can expedite weight loss and result in your body burning more fat.
Ketosis is the result of following the ketogenic diet, which is why it’s also sometimes called “the ketosis diet.” Ketosis takes place when glucose from carbohydrate foods (like grains, all sources of sugar or fruit, for example) is drastically reduced, which forces the body to find an alternative fuel source: fat. Although dietary fat (especially saturated fat) often gets a bad name, provoking fear of weight gain and heart disease, it’s also your body’s second preferred source of energy when carbohydrates are not easily accessible.
Because it also requires drastic carbohydrate restriction, complete or intermittent fasting can also induce states of ketosis. However, total fasting, which would result in a level of ketosis comparable to the ketogenic diet, isn’t easy to maintain beyond a few days.
In the absence of glucose, which is normally used by cells as a quick source of energy, the body starts to burn fat and produces ketones instead. Once ketone levels in the blood rise to a certain point, you enter into a state of ketosis— which usually results in quick and consistent weight loss until you reach a healthy, stable body weight.
Let’s go through that again, step by step. What is ketosis? Here’s how it works:
- Consumption of glucose from carbohydrate foods — grains, starchy vegetables, fruit, etc. — is cut way down.
- This forces your body to find an alternative fuel source: fat (think avocados, coconut oil, salmon).
- Meanwhile, in the absence of glucose, the body also starts to burn fat and produces ketones instead.
- Once ketone levels in the blood rise to a certain point, you enter into a state of ketosis.
- This state results in quick and consistent weight loss until you reach a healthy, stable body weight.
To sum up a complex process, ketosis happens when the liver breaks down fat into fatty acids and glycerol, through a process called beta-oxidation. There are three primary types of ketone bodies that are water-soluble molecules produced in the liver: acetoacetate, beta-hydroxybutyrate and acetone.
The body then further breaks down these fatty acids into an energy-rich substance called ketones that circulate through the bloodstream. Fatty acid molecules are broken down through the process called ketogenesis, and a specific ketone body called acetoacetate is formed which supplies energy.
The end result is staying fueled off of circulating ketones (which are also sometimes called ketone bodies) — which is what’s responsible for altering your metabolism in a way that some people like to say turns you into a “fat-burning machine.”
The goal of the ketogenic diet is to keep you in this fat-burning metabolic state of ketosis. This is achieved by following a very low-carbohydrate, high-fat diet that includes only moderate amounts of protein. Foods like bread, cereal, processed snacks and sugary drinks are therefore off the table, while fattier foods like butter, grass-fed beef, fish and also non-starchy veggies take center stage, providing the majority of daily calories (as much as 70–80 percent).
How long does it take to get into ketosis? This will depend on a few factors, including how strictly you limit your carb intake and also certain variables that are mostly out of your control, like your genetics, medical history, body composition and energy needs.
Wondering what signs to look out for when you know you’re in or on your way to reaching ketosis? Healthline provides some symptoms to look for, and we include three of them below:
Ketogenic diets, along with normal low-carb diets, are highly effective for weight loss (5, 6).
As dozens of weight loss studies have shown, you will likely experience both short- and long-term weight loss when switching to a ketogenic diet.
Fast weight loss can occur during the first week. While some people believe this to be fat loss, it’s primarily stored carbs and water being used up.
After the initial rapid drop in water weight, you should continue to lose body fat consistently as long as you stick to the diet and remain in a calorie deficit.
Ketones in the Blood
One of the hallmarks of a ketogenic diet is a reduction in blood sugar levels and an increase in ketones.
As you progress further into a ketogenic diet, you will start to burn fat and ketones as the main fuel sources.
The most reliable and accurate method of measuring ketosis is to measure your blood ketone levels using a specialized meter.
It measures your ketone levels by calculating the amount of beta-hydroxybutyrate (BHB) in your blood.
This is one of the primary ketones present in the bloodstream.
According to some experts on the ketogenic diet, nutritional ketosis is defined as blood ketones ranging from 0.5–3.0 mmol/L.
Measuring ketones in your blood is the most accurate way of testing and is used in most research studies. However, the main downside is that it requires a small pinprick to draw blood from your finger.
What’s more, test kits can be expensive. For this reason, most people will just perform one test per week or every other week. If you would like to try testing your ketones, Amazon has a good selection available.
any people report decreased hunger while following a ketogenic diet.
The reasons why this happens are still being investigated.
However, it's been suggested that this hunger reduction may be due to an increased protein and vegetable intake, along with alterations to your body's hunger hormones.
The ketones themselves may also affect your brain to reduce appetite.
Typically it can take three to four days to enter ketosis, and Web MD mentions a few benefits of ketosis such as potentially preventing seizures.
For healthy people who don't have diabetes and aren't pregnant, ketosis usually kicks in after 3 or 4 days of eating less than 50 grams of carbohydrates per day. That's about 3 slices of bread, a cup of low-fat fruit yogurt, or two small bananas. You can start ketosis by fasting, too.
Doctors may put children who have epilepsy on a ketogenic diet, a special high-fat, very low-carb and protein plan, because it might help prevent seizures.
Some research suggests that ketogenic diets might help lower your risk of heart disease. Other studies show specific very-low-carb diets help people with metabolic syndrome, insulin resistance, and type 2 diabetes. Researchers are also studying the effects of these diets on acne, cancer, polycystic ovary syndrome (PCOS), and nervous system diseases like Alzheimer's, Parkinson's, and Lou Gehrig's disease.
If your body reaches ketosis, you can enjoy many benefits, and we discuss this and more in the Body Reboot book. If you want a free book help us cover shipping and visit this page to get your free copy today!
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