The keto (short for ketogenic) diet has been around for centuries. Endocrinologist Rollin Woodyatt discovered a century ago that when a person fasts or follows a high-fat, low-carbohydrate diet, the liver produces ketone bodies (acetone, -hydroxybutyrate, and acetoacetate).
At that time, fasting was part of the treatment of epilepsy in children. Because changing one’s diet was easier than fasting, a keto diet became a preferred therapy for epilepsy.
Over the past century, the ketogenic diet has been closely studied for its potential to treat other conditions, including diabetes, cancer, and Alzheimer’s disease. Lately,Lately it is gaining popularity as a weight loss strategy.
So how much weight can you lose on keto? Let’s take a closer look at that.
How does a ketogenic diet work?
Your body’s favourite fuel is glucose (sugar), which comes from carbohydrates. When you eat fruits, vegetables, grains, and legumes, you get fuel that keeps your body functioning.
The keto diet forces your body to switch from sugar to ketone bodies, which your liver creates from stored fat for energy production.The metabolic state in which your body predominantly uses ketone bodies instead of glucose is called ketosis.
It usually takes several days to reach ketosis. The exact time depends on your resting metabolism, body fat percentage, level of physical activity, and, most importantly, your daily carbohydrate intake.
How to Lose Weight on a Ketogenic Diet
To kick-start ketosis, eat no more than 20 to 50 grammes of carbs per day. However, the exact number will depend on your individual traits.
Carbohydrates
To consume fewer carbohydrates, eliminate grains, sweets, and sugary soft drinks from your diet. You should also eat fewer fruits and vegetables.
In fact, your vegetable consumption should be limited to leafy greens, cauliflower, broccoli, asparagus, cucumbers, celery, and a few other options. For fruits, you should limit yourself to berries.
Fats
While you can consume some unsaturated fats such as almonds, walnuts, olive oil, avocados, and tofu, you should focus on including plenty of saturated fats in your diet. They include coconut oil, butter, cocoa butter, and lard.
Protein
Protein is allowed in a keto diet. The best protein for ketosis is high in saturated fat, such as beef, bacon, and pork.
For a ketogenic diet, the recommended2 ratios are 70-80% fat, 5-10% carbohydrates, and 10-20% protein.
How much weight can you lose on keto?
When you are in ketosis, you are actively burning stored fat, resulting in weight loss. However, the amount of weight you can lose depends on several factors:
Calorie intake
A keto diet can be very high in calories. The amount of weight you lose depends on how well you control your calorie intake.
General health
If you are overweight, have thyroid problems, or have blood sugar problems, it may take longer for weight loss to start. More importantly, ketosis can sometimes be dangerous for people with chronic health conditions.
Metabolism
Because the time it takes for different people to reach ketosis varies, some people begin to lose weight faster than others.
Lifestyle
Sleep quantity and quality, water consumption, and activity level can affect your keto weight loss.
Coherence
People who religiously adhere to the keto diet can achieve better weight loss results.
If a person follows the 75% fat, 20% carbs, and 5% fat keto diet, the average results might look like this:
- Weeks 1–2: Phase of rapid weight reduction through water loss (up to ten pounds)
- Weeks 2–4: Standard weight reduction—between one and two pounds per week
- After the first month, there is slow weight loss, about a pound a week.
While many people expect quicker results, losing one to two pounds per week3 is a healthy rate.Consistent rapid weight loss can lead to serious health problems.
How Fast Can You Lose Weight With Keto?
The rate of weight loss depends on your initial body mass index (BMI) and body fat percentage. People with a higher BMI tend to lose more weight at the start of a keto diet.
Once you start dieting and start burning stored carbs, the water that binds them leaves your body. You will probably have to urinate often.
As the excess water comes out, you may notice rapid weight loss. This usually occurs within the first two weeks of starting the diet. As you continue your keto diet, weight loss will slow down significantly.
According to one study4, the keto diet can help you lose weight faster than a low-fat diet.However, this does not mean that you will see drastic results. The stories you may have heard about significant weight loss on a ketogenic diet usually come from people who follow it for one or two weeks.
What are the risks of keto?
Changing the way your body works can carry several risks. For this reason, it is important to consult a doctor before starting the keto diet to adjust your metabolism. While it can be effective for some people, this diet can be dangerous for others in several ways:
Heart disease
Since the keto diet involves eating high amounts of saturated fats, it can increase your risk of developing heart disease.
A deficiency of nutrients
Once you start restricting vegetables, fruits, and grains, your body is deprived of essential nutrients such as vitamins B and C, magnesium, selenium, and others. This can lead to serious health problems, including heart disease, infertility, cognitive decline, mental illness, and much more. Pregnant women may not get enough folic acid, which can lead to birth defects.
Liver disease
If you have existing liver conditions, forcing the organ to metabolise excess fat can make them worse.
Kidney problems
A keto diet can overload your kidneys as they work to metabolise protein.
Constipation
As you cut down on fiber-rich foods (grains, vegetables), you may get constipated.
Decreased muscle mass
If you restrict calorie intake on a keto diet at the expense of high-protein foods, you could lose muscle mass.
Ketoacidose
In people with type 1 diabetes, a ketogenic diet can cause the body to store too many ketones. This can cause the blood to become acidic and damage the liver, kidneys, and brain. In rare cases, ketoacidosis occurs in healthy people.
A long-term ketogenic diet may do more harm than good, according to a study5 published in Frontiers in Nutrition.It is unsafe for people with liver problems, kidney disease, and diabetes. In addition, the diet contains many foods associated with a high risk of cancer.
Even if a person is healthy, keto’s proportion of macronutrients may make it unsafe for continued use. While a relevant study6 found that increasing the fat to carbohydrate ratio in the diet is beneficial, the safety of the amount of fat typically found in a ketogenic diet is still unknown.After a few weeks of dieting, consider discussing a less aggressive approach with your doctor.
What are the challenges of losing weight on keto?
While keto can help you lose weight, sticking to this diet is often challenging. Extreme carbohydrate restriction can cause unpleasant symptoms such as hunger, fatigue, mood swings, headaches, dizziness, and constipation.
Symptoms will disappear over time. However, in some people, they can last for weeks before giving way to carbohydrate cravings.
It’s important to understand that a keto diet, while effective, is not a quick way to lose weight. As with any low-calorie diet, you will notice drastic weight loss in the first few weeks, followed by a steady decline.
The nadir
The keto diet changes the way your metabolism works by encouraging it to use ketone bodies instead of glucose for energy production. In the first few weeks, it is possible to lose up to ten pounds. After that, you should be able to lose one to two pounds per week.
Since keto can have serious side effects, talking to your doctor or dietician before starting it can prevent unpleasant consequences for your health.