The ketogenic diet (also known as the keto diet) is a very low-carbohydrate diet that turns your body into a fat-burning machine. It offers many benefits for weight loss, health and performance, but also has some side effects.
This diet is similar to other low-carbohydrate diets, such as Atkins or LCHF (low-carbohydrate, high-fat). These diets end up being more or less ketogenic by accident. The main difference between the strict LCHF diet and the ketogenic diet is that the latter limits protein intake.
The ketogenic diet approach is specially designed to cause the state of ketosis in the body. It is possible to measure and adapt food to achieve the optimal level of ketones for health, weight loss, or to improve physical and mental condition.
In this article we explain how to use this method to achieve your personal goals.
What is Ketosis?
The ketogenic diet is so called because it causes your body to produce small fuel molecules called ketones. This is a type of fuel or energy your body uses when your blood sugar (glucose) level is low.
Ketones are produced when you consume few carbohydrates (which are quickly converted to glucose) and a moderate amount of protein (an excess of protein can also be converted to glucose).
These ketones are produced in the liver from fat. They are then used as fuel throughout the body, including the brain. The brain is a hungry organ that consumes a lot of energy all the time, and cannot operate on fat directly. It can only function on the basis of glucose… or ketones.
Under a ketogenic diet, your whole body changes its fuel source to operate almost entirely on fat. Insulin levels reach a very low level and fat burning rises dramatically. Your body has easy access to fat deposits to burn them and turn them into fuel.
This is excellent news if you are trying to lose weight, but there are also other less obvious benefits, such as less feeling of hunger and a continuous supply of energy to your body.
When your body produces ketones, it is said to be in a state of ketosis. The fastest way to get there is by fasting – not eating anything – but of course it is not always possible to fast.
However, a ketogenic diet can be worn indefinitely and cause ketosis in your body. It offers much of the benefits of fasting (including weight loss) without having to go hungry.
Who should NOT follow a Ketogenic Diet?
Most people can follow a ketogenic diet without any problems. But in the following cases, you may need some extra preparation or adaptation:
- You are on diabetes medication (e.g. insulin)
- You’re on medication for high blood pressure.
- You are breast-feeding
Keto Diet Benefits
The benefits of this diet are similar to those of low-carbohydrate diets. However, the effect is multiplied as we also restrict protein. This causes them to produce more ketones, and lower levels of insulin (the hormone that stores fat).
1. Weight Loss
Turning your body into a fat burning machine logically offers many weight loss benefits. Fat burning rises dramatically when insulin levels (the hormone responsible for storing fat) drop dramatically. This creates an ideal environment for fat loss to occur without feeling hungry.
About 20 of the most accurate scientific studies (RCTs) show that, compared to other diets, the ketogenic low-carbohydrate diet offers much more efficient weight management.
2. Correction of Type 2 Diabetes
The keto diet is excellent for reducing or totally correcting type 2 diabetes, as it significantly decreases blood sugar levels and the negative impact of having a high insulin level.
3. Improved Mental Concentration
Ketosis provides a stable flow of fuel (ketones) to the brain. Under the ketogenic diet, you avoid radical changes in your blood sugar levels. This usually means higher and better concentration.
Many people practice this diet especially for the benefit of better concentration it offers.
Interestingly, there is a misperception that we need to consume a lot of carbohydrates in order for our brain to function optimally. But this is only true if we don’t have ketones available.
After a few days (1 week maximum) of keto-adaptation (period where you are likely to have difficulty concentrating, headaches or mood swings) your body and brain can function using ketones exclusively without any problems.
When we reach this state, we will be able to feel much more energy and mental acuity/concentration.
4. Increased Physical Performance
Ketogenic diets can greatly increase your physical performance by giving you constant access to all the energy stored as fat in your body.
The supply of stored carbohydrates (glycogen) only lasts a couple of hours (or less) after doing some kind of intense activity or exercise. But your fat reserves contain enough energy to keep you going for weeks or even months.
When you’re used to running mainly on carbohydrates (as most people do today) your fat reserves are not readily available, so they can’t fuel your brain.
This means that we have to supply our body constantly before, during and after long exercise sessions. Or even just to provide the energy needed for our daily activities and avoid hunger and bad mood.
Under a ketogenic diet this problem is solved. As the body and brain can be easily fed 24 hours a day through your fat reserves, you can continue your daily rhythm without any problem.
Whether you’re competing in a stamina event or just keeping focused on a goal, your body will have the fuel it needs to help you keep moving.
5. Metabolic Syndrome
There are many studies showing that low-carbohydrate diets improve markers of metabolic syndrome, such as blood lipids, insulin levels, HDL cholesterol, LDL particle size, and glucose levels.
Improvements are even greater when carbohydrates and protein are continuously restricted to such an extent in nutritional ketosis.
The ketogenic diet is a proven medical therapy for epilepsy that has been used since 1920. Traditionally, it has been used primarily in children with uncontrolled epilepsy despite being on medication.
It has now also been successfully tested in adults with epilepsy, with similar results. There are many randomised controlled studies demonstrating the effectiveness of this diet in reducing seizures in patients with epilepsy.
Such a diet in epilepsy allows patients to take much less medication and at the same time be safe from seizures.
As all anti-seizure medications have side effects (such as drowsiness, low concentration, personality changes, or even reduced IQ), being able to take fewer anti-seizure medications can be quite beneficial for the patient.
What to Eat During a Ketogenic Diet Weekly Menu
These are the most common foods in a ketogenic diet. The numbers are net carbohydrates per 100 grams. To keep us in a state of ketosis, low numbers are always better:
The most important thing to achieve ketosis is to avoid eating most carbohydrates. You will probably need a intake below 50 grams per day, ideally below 20 g. The less carbohydrates, the more effective your diet will be.
This means that you will have to completely eliminate foods with sugar, and also starchy foods such as bread, pasta, rice or potatoes. Basically you have to follow the rules of a low-carbohydrate diet, but remember it’s supposed to be high in fat, not protein.
A general pattern of energy distribution would be:
- 10% from carbohydrates (the less carbohydrates, the more effective)
- 15-25% protein (15% being ideal)
- And 70% or more fat
How To Know If We’re In Ketosis
How do you know if you are in a state of ketosis? It is possible to measure it by means of urine tests, blood or breath samples. But there are also some symptoms that do not require samples, such as:
- Dry mouth and increased thirst. Unless you drink enough water and get enough electrolytes, such as salt, your mouth may feel a little dry. Try 1 or 2 cups of bouillon soup a day, and also drink as much water as you can.
- Increased urination. Another component of ketone, acetoacetate, can end up in the urine. This makes it possible to test for ketosis through urine strips. It can also result (at least at first) in going to the bathroom more often. This is the main cause of increased thirst (first point).
- Ketogenic breath – this must be component of the ketone called acetone that escapes through our breath. It can make a person’s breath smell “fruity,” or similar to that of a nail polish remover. This smell can also come out when you sweat, while doing any activity. It’s usually temporary.
Other less specific but more positive signs may be:
- Decreased appetite – many people experience a significant reduction in appetite. This is possibly caused by increasing the body’s ability to use fuel stored in fat reserves. Many people feel good eating only once or twice a day, and end up doing some sort of intermittent fasting. This saves both time and money, and also helps speed up weight loss.
- Increased energy – it is likely that after a couple of days of feeling tired (keto flu) many people experience an increase in energy levels. Some experience it as clear thinking, decreased “mental fog” or even a sense of euphoria.
How to Achieve Ketosis Status
There are many things that can increase your ketosis level. Here I present them in order of importance (higher to lower):
- Restrict carbohydrates to 20 grams per day or less – a strict low-carbohydrate diet. There’s no need to restrict fiber, it can even be beneficial.
- Restricts protein to moderate levels. It is possible to keep us at 1 gram of protein per day, per kilo of weight. If you weigh 70 kilos (154 pounds), the equivalent would be about 70 grams of protein. It might actually be beneficial to lower it even more, especially for people who are somewhat overweight, aiming at 1 g of protein per kilo depending on target weight. The main mistake preventing many people from staying in an optimal ketosis state is consuming too much protein.
- Consume enough fat to feel satisfied. This is the main difference between a ketogenic diet and starvation, which also results in ketosis. A ketogenic diet is sustainable, starvation is not.
- Avoid pecking or snacking when you are not hungry. Eating snacks slows weight loss and reduces ketosis.
- If necessary, add intermittent fasting. This method is very effective in boosting ketone levels, as well as accelerating weight loss and controlling type 2 diabetes.
Possible Side Effects of Ketosis
Can a high level of ketones be dangerous? Not under normal circumstances.
For most people, it is a great challenge just to get an optimal ketosis. Achieving dangerous ketone levels (more than 8-10 mmol of ketones in the blood) in most cases is almost impossible.
The main exception is type 1 diabetes, where the pancreas does not produce enough insulin. In this type of diabetes it is very possible to achieve dangerous levels of ketones, but it can be avoided by stopping insulin injections.
There are also other situations such as breastfeeding (mothers) and taking type 2 diabetes medications called SGLT-2 inhibitors, which under some situations can result in a high number of ketones.
All of this causes feeling sick, nausea and weakness. It could also become a life-threatening condition called ketoacidosis.
There is a very simple treatment if you suspect this may be happening to you: eat carbohydrates immediately (for example a couple of fruits, a sandwich or a glass of juice). If you have type 1 diabetes, take more insulin. Contact emergency medical services if you don’t start feeling better right away.
People who are transitioning from a sugar-based diet to a fat-based diet usually experience side effects.
Many refer to this as the Ceto Flu, as the symptoms are similar to those of the common flu: fatigue, nausea, headaches, ramps, etc.
There are 2 things you can do to prevent or alleviate these temporary symptoms:
- Drink water with salt and lemon – alternatively you can have bouillon soup.
- Gradually reduce carbohydrate intake – making the change very radical (from sugar to fat) can result in greater symptoms of this type.
Here is a very instructive video about the ketogenic diet explained by Dr. Oz. Enjoy.