The keto diet is a high-fat, low-carbohydrate diet. This approach encourages the body to switch from using carbohydrates for energy to using fat, helping support weight management and metabolism.
In this article, we discuss the benefits of the keto diet, its potential risks, and strategies for long-term success. You will learn about faster weight loss, improved cognitive function, potential cardiovascular risks, and the risk of nutrient deficiencies.
At a glance
- Rapid weight loss: The keto diet drastically reduces carbohydrate intake, triggering ketosis, a state in which the body burns fat as its main source of energy.
- Health benefits: Improved metabolic health, greater mental clarity, and neurological benefits, such as fewer seizure episodes.
- Potential risks: High intake of saturated fat, nutrient deficiencies, and digestive problems caused by a low-fibre diet.
- Sustainability challenges: The high demand for animal-based foods can make the diet expensive due to the cost of high-quality ingredients.
- How to avoid problems: Choose whole foods and consult healthcare professionals to help ensure the diet remains balanced and sustainable over the long term.
Keto diet
The ketogenic diet, also known as the keto diet, focuses on a low carbohydrate and high fat intake in order to encourage a metabolic state called ketosis. The diet was developed by Russell Wilder in 1920 for the treatment of epilepsy, particularly in cases that were resistant to medication. It causes a significant shift in the body's primary source of energy.
During ketosis, the body begins to use fat as its main source of energy instead of carbohydrates. This process occurs when carbohydrate intake is reduced to around 20–50 grams per day. The liver then begins converting fat into ketone bodies, which provide an alternative source of energy for the body.
A standard ketogenic diet contains approximately 55–60% fat, 30–35% protein, and 5–10% carbohydrates. Studies show that the keto diet may help reduce the risk of type 2 diabetes and heart disease while improving glucose control and insulin sensitivity. One of the main reasons people choose this diet is its effectiveness for weight loss, as it can often outperform traditional low-fat diets.
The keto diet can also provide a stable source of energy, particularly during a calorie deficit. This dietary approach can be adapted to individual needs, including cyclical or targeted ketogenic diets for active people or athletes.
The basic principle of the diet is to limit carbohydrate-rich foods such as bread and sugar while consuming foods that are higher in fat, including meat, oils, avocados, and nuts.
To follow the keto diet successfully, it is important to understand its basic principles and consult a doctor before making significant changes to your diet. It is also important to drink enough water to support normal body function.
Benefits of the keto diet
The keto diet may offer a number of benefits, including rapid weight loss, improved metabolic health, and neurological effects.
Weight loss and fat burning
Because of its low carbohydrate intake and the resulting state of ketosis, the keto diet may reduce appetite and help lower overall calorie intake. The body begins using fat as its main source of energy, breaking it down into ketones. This process can be particularly effective for reducing visceral fat, which is stored around the abdominal area, while helping preserve muscle mass.
Heart health
The keto diet may support heart health when it includes healthier sources of fat such as avocados, olive oil, and nuts. These fats may increase levels of HDL, often referred to as “good” cholesterol, and lower triglyceride levels, which may help reduce the risk of heart disease.
Metabolic benefits
This diet may help regulate blood sugar and insulin levels, which can be beneficial for people with diabetes or insulin resistance. The keto diet may also improve the cholesterol profile and contribute to better overall metabolic health.
Neurological benefits
The keto diet has long been used in the treatment of epilepsy because it can help reduce the number of seizures. It may also be beneficial for people with Alzheimer's disease and may have a positive effect on polycystic ovary syndrome (PCOS). Ketones provide an efficient source of energy for the brain and may support mental clarity and stable energy levels.
The potential benefits of the keto diet include weight loss, better heart health, stable blood sugar levels, and neurological effects. When applied appropriately, the diet may appeal to people who are focused on their health and wellbeing.
Risks of the keto diet
Although the keto diet may offer a number of benefits, it is also associated with certain risks that should be considered before starting it.
Cardiovascular health
A high intake of saturated fat on the keto diet may raise LDL, often referred to as “bad” cholesterol, which could increase the risk of cardiovascular disease. It is therefore important to prioritise healthier fats such as avocado oil and olive oil.
Kidney strain
Excessive protein intake may place additional strain on the kidneys, particularly in people who already have kidney health problems. In such cases, this diet may not be recommended.
Nutrient deficiencies
Restricting carbohydrates often reduces the amount of fruit and vegetables consumed, which can lead to deficiencies in vitamins and minerals such as magnesium, potassium, and vitamin C. Reduced fibre intake may also cause digestive problems such as constipation.
Potential health complications
For people with diabetes or kidney disease, the keto diet may increase the risk of diabetic ketoacidosis or other complications. It is therefore important to consult a doctor before starting this diet.
Potential negative effects for certain groups
Pregnant and breastfeeding women following a keto diet may experience nutrient deficiencies that could affect the health of the baby. In addition, carbohydrate restriction during the early stages of the diet often causes what is known as the “keto flu”, which may involve fatigue, mood changes, and confusion.
Bone health and long-term sustainability concerns
Some studies suggest that following a keto diet may negatively affect bone mineral density, raising questions about the diet's long-term effects on health.
Main components of the keto diet
To follow the keto diet successfully, it is important to understand its main components: the appropriate macronutrient ratio and careful food selection.
Macronutrient ratio
The key to the keto diet is maintaining the right balance of fats, proteins, and carbohydrates to help the body reach ketosis. A typical diet consists of:
- 70–80% fat: Fat is the primary energy source, so it is important to choose healthier fats such as olive oil, avocados, nuts, and coconut oil.
- 10–20% protein: Protein intake should remain moderate so that the body stays in ketosis.
- 5–10% carbohydrates: Restricting carbohydrate intake is necessary for the body to begin producing ketones.
Why is it important to follow these proportions?
This macronutrient distribution helps the body switch its main energy source from glucose, which comes from carbohydrates, to fat through the production of ketones. Maintaining the right balance helps the diet achieve and maintain this metabolic state.
Ketogenic diet model
Some versions of the keto diet use an even stricter macronutrient ratio, such as 4:1, with 90% fat, 6% protein, and 4% carbohydrates. This model is more commonly used for medical purposes, such as the treatment of epilepsy. For everyday use, however, a more flexible approach is generally used to help maintain nutritional balance.
Choosing the right foods
When following the keto diet, it is important to choose foods that are rich in healthy fats, such as:
- Avocados,
- Nuts and seeds,
- Olive oil and coconut oil,
- Fatty fish such as salmon and mackerel.
At the same time, carbohydrate-rich foods such as bread, pasta, and sweets should be limited because they can interrupt ketosis.
Keto diet variations
The ketogenic diet can be adapted to individual goals by changing the proportions of fat, protein, and carbohydrates consumed. The main types of keto diet and their macronutrient ratios are shown below:
| Diet type | Fat (%) | Protein (%) | Carbohydrates (%) |
|---|---|---|---|
| Classic keto | 90% | 6% | 4% |
| Modified keto (3:1) | 87% | 10% | 3% |
| Modified keto (1:1) | 70% | 15% | 15% |
These variations allow the diet to be adapted to specific health goals, such as weight loss or maintaining stable energy levels.
How do you choose the right type of keto diet?
- Classic keto: Most commonly used for medical purposes, such as epilepsy treatment. This version involves a strict high-fat and very low-carbohydrate intake.
- Modified keto (3:1): Suitable for people who want to consume more protein while maintaining strict carbohydrate control.
- Modified keto (1:1): Offers greater flexibility and may suit people looking for a more balanced eating plan with a lower fat intake.
Why is it important to understand the macronutrient ratio?
Following these proportions helps the body enter ketosis effectively, allowing fat to become its main source of energy. This may support weight loss, help stabilise energy levels, and improve concentration.
Medical applications of the keto diet
The keto diet is well known for its use in treating epilepsy, particularly in cases that are resistant to medication. Research suggests that this diet may also have positive effects on mental health and energy stability.
Overview of food choices
The ketogenic diet focuses on specific food groups that help maintain the appropriate macronutrient ratio. The main choices include:
Meat and poultry
Choose red meat, poultry, and game, preferably grass-fed where possible. These foods provide high-quality protein and contain no carbohydrates, helping to preserve muscle mass.
Low-carbohydrate vegetables
Include non-starchy vegetables such as:
- Spinach,
- Cabbage,
- Broccoli,
- Cauliflower.
These vegetables are rich in vitamins, minerals, and antioxidants that contribute to overall health.
Healthy fats and dairy products
- Extra virgin olive oil and avocado oil are excellent sources of healthy fats.
- Fatty fish, such as salmon, provides essential omega-3 fatty acids.
- Nuts and seeds provide healthy fats while containing relatively few carbohydrates.
- Higher-fat dairy products such as cheese, sour cream, and butter.
Additional keto-friendly foods
- Eggs are versatile and nutritious.
- Berries, such as raspberries and wild blueberries, can be enjoyed in moderation because they contain relatively few carbohydrates.
- Dark chocolate containing more than 85% cocoa can be a suitable dessert option.
Drinks and condiments
- Unsweetened drinks such as water, tea, and coffee are suitable.
- Some condiments, such as mustard or vinegar-based sauces, can add flavour to meals without adding significant amounts of carbohydrates.
Including these foods in your daily diet can help support a balanced and successful approach to the keto diet.
Expert recommendations
To follow the keto diet successfully, it is important to consider these main recommendations:
- Consult your doctor
- A doctor can help adapt the diet to your health condition and goals.
- They can provide guidance on maintaining a balanced nutrient intake and help prevent deficiencies.
- They can assess possible interactions with medications, particularly for people with diabetes or chronic health conditions.
- Monitor your nutrient intake
- Make sure your diet provides adequate vitamins, minerals, and fibre.
- Choose healthier fats such as olive oil and fatty fish while avoiding excessive consumption of saturated fat.
- Regularly assess the effects of the diet
- Regular visits to your doctor can help monitor your long-term health and ensure the diet remains safe and effective.
- Your doctor can assess whether the diet is suitable for your long-term weight-management needs.
These recommendations can help you follow the keto diet more safely and achieve the best possible results.
Monitor your nutrient intake
While following a ketogenic diet, it is important to make sure you receive enough essential nutrients:
- Commonly lacking nutrients: Vitamins B7, B12, D, E, and K. Minerals: magnesium, potassium, iron, calcium, and selenium. Omega-3 fatty acids are important for heart and brain function.
- Testing and monitoring: Consider blood tests that assess electrolyte and micronutrient levels. Monitor blood ketone levels, which may range between 0.5–3 mg/dl.
- Supplements and adjustments: If nutrient deficiencies are identified, supplements such as magnesium or vitamin D may be considered. Plan a balanced diet that includes vegetables and healthy fats.
- Monitoring symptoms: Fatigue and “brain fog” may indicate a nutrient deficiency. Consult your doctor if these symptoms occur.
Regular medical check-ups can help ensure that your diet remains sustainable and appropriately balanced.
Choose healthy fats
Fat provides the majority of calories in a ketogenic diet, so choosing appropriate sources is particularly important:
- Saturated fats: Sources include coconut oil, MCT oil, and butter. These fats provide quick energy, do not affect insulin levels, and may increase HDL, often referred to as “good” cholesterol.
- Monounsaturated fats: Sources include avocados, olive oil, and nuts. These fats may help lower blood pressure and cholesterol, improve blood sugar control, and help reduce inflammation.
- Polyunsaturated fats: Sources include fatty fish such as salmon and mackerel, nuts, and seeds. The omega-3 fatty acids they contain support brain function and heart health and may help reduce inflammation.
Include olive oil or avocado oil in salads, eat fatty fish, and use coconut or MCT oil when cooking. These choices may help support overall wellbeing.
Can you drink alcohol on a keto diet?
Yes, but it should be consumed in moderation, and lower-carbohydrate drinks should be chosen.
- Suitable options: Pure spirits such as vodka or whisky, or dry wines.
- Avoid: Beer and sweet cocktails containing sugar.
Alcohol can temporarily interrupt ketosis because the body prioritises metabolising alcohol rather than burning fat. It may also cause faster intoxication and more severe hangovers.
Tip: Drink plenty of water and eat a small, high-fat meal before consuming alcohol.
How long does it take to lose weight on keto?
The first results are usually noticeable within 10–21 days.
- First week: Most of the initial loss is water weight, around 1–10 kg.
- Afterwards: Steady weight loss may be around 1 kg per week.
Results depend on factors such as metabolism, body composition, and how consistently the diet is followed. Progress can vary from person to person.
Are there vegetarian versions of the keto diet?
Yes. A vegetarian keto diet can be adapted by focusing on high-fat, low-carbohydrate plant-based foods.
Main components include non-starchy vegetables, healthy fats such as olive oil and avocados, nuts, seeds, tofu, and higher-fat dairy products.
It is important to plan protein intake carefully and control carbohydrate consumption in order to maintain ketosis.
What snacks are suitable for the keto diet?
Keto-friendly snacks are foods that are low in carbohydrates and higher in fat or protein:
- Nuts and seeds: Almonds, walnuts, and chia seeds.
- Vegetables: Cucumbers and celery with nut butter or another healthy spread.
- Dairy products: Full-fat sour cream, cheese, and plain Greek yoghurt.
- Protein-rich snacks: Hard-boiled eggs, beef jerky, and pieces of chicken.
These snacks can help provide satiety and energy while following the principles of a ketogenic diet.
Will the keto diet affect my workout performance?
Yes, the keto diet may affect workout performance depending on the type of exercise and individual characteristics:
- Endurance exercise: Fat utilisation may increase, and endurance during longer sessions may improve.
- High-intensity exercise: Reduced glycogen stores may negatively affect performance and increase fatigue.
For some athletes, the keto diet may support recovery and help maintain muscle mass, while others may find it more difficult to maintain their energy levels.
Recommendation: If your training is intense, consider strategically consuming carbohydrates at certain times, such as before exercise, to help support energy stores.
Final thoughts
The keto diet is a distinctive approach to weight management and metabolic health. It is based on a high fat and low carbohydrate intake. Although the diet may offer benefits such as faster weight loss and improved cognitive function, it is important to consider potential risks, including increased LDL cholesterol levels and nutrient deficiencies.
For long-term success, it is advisable to choose a balanced and sustainable approach to eating, with a focus on whole foods and professional guidance. A responsible approach can help make this dietary strategy safer and more effective.
