Ketogenic diet: what to eat, sample plans and contraindications

If you are looking for an effective way to lose weight and improve your overall health, you may have heard of the ketogenic diet. But what exactly is the ketogenic diet and how does it work? In this article we will explore all the fundamental aspects of this diet, including what to eat, sample meal plans and potential contraindications.

Ketogenic diet: what it is

The ketogenic diet, often shortened to the "keto diet", is an eating plan that is high in fat, moderate in protein and very low in carbohydrates. The main aim of this diet is to induce a metabolic state called ketosis, in which the body burns fat for energy instead of carbohydrates. This process produces ketones, which the body uses as an alternative source of energy.

Ketosis and diet

Ketosis is a metabolic state in which the body uses fat as its primary source of energy instead of carbohydrates. This process occurs when carbohydrate intake is drastically reduced, as happens on the ketogenic diet. During ketosis, the liver converts fat into ketones, which are used as an alternative fuel by the body's cells, including the brain.

Here is how ketosis occurs on the ketogenic diet:

1. Increasing fat intake: To make up for the reduction in carbohydrates, the ketogenic diet is rich in healthy fats, which make up about 70-80% of total daily calories. These fats are used as the body's primary fuel and the liver starts converting them into ketones.

Ketone production: When the body is deprived of glucose, the liver starts converting fat into ketones through a process called ketogenesis. Ketones are molecules that can cross the blood-brain barrier and provide energy to the brain and other cells of the body.

1. Entering ketosis: After a few days of carbohydrate restriction, the body enters a state of ketosis, in which blood ketone levels rise and the body mainly uses fat as fuel. This state can be confirmed with ketosis test strips or with more precise tests such as blood or urine ketone meters.

Ketogenic diet: benefits, weight loss and results
The ketogenic diet has become popular not only for general weight loss, but also for its ability to produce significant weight-loss results in a short period of time, even up to 20 kg. Here are the main reasons:

1. Rapid induction of ketosis: The ketogenic diet is designed to quickly induce the metabolic state of ketosis, in which the body starts burning fat for energy instead of carbohydrates. This can lead to rapid initial weight loss, as the body uses stored fat as its primary source of fuel.
2. Appetite control: A ketogenic diet is rich in fat and protein, which are highly satiating nutrients. Eating foods that promote satiety can reduce appetite and help limit overall calorie intake, which can make weight loss easier.
3. Less bloating: By reducing carbohydrate intake, the ketogenic diet can help reduce the bloating caused by fluid retention linked to excessive carbohydrate intake. This can lead to a temporary reduction in body weight due to the reduced bloating.
4. Initial weight loss: Many people who follow the ketogenic diet lose a significant amount of weight in the first weeks on the diet. This may be due to a combination of body fat loss, fluid loss and reduced appetite.
5. Promoting fat loss: Ketosis is associated with increased ketone production, which may have positive effects on fat burning. As a result, the ketogenic diet can be effective in promoting body fat loss, which can lead to a significant reduction in overall body weight over time.

It is important to note that weight loss can vary from person to person and depends on many factors, including individual metabolism, age, sex, physical activity and more.

Ketogenic diet: what to eat

The foods allowed on the ketogenic diet mainly include healthy fats, lean proteins and limited amounts of carbohydrates. Here are some examples of foods you can eat and use in your recipes:

• Healthy fats: Avocado, olive oil, butter, nuts and seeds.
• Lean proteins: Lean meat, fish, eggs and dairy products.
• Low-carbohydrate vegetables: Spinach, cauliflower, broccoli and courgettes.
• Small amounts of low-sugar fruit: Strawberries, blueberries, raspberries.
• Ketogenic foods: Full-fat cheeses, beef, chicken, pork.

Avoid carbohydrate-rich foods such as bread, pasta, rice, potatoes and refined sugars.

Sample ketogenic diet

Here is a sample meal plan:

Day 1

• Breakfast: Scrambled eggs with avocado.
• Lunch: Chicken salad with olive oil and avocado.
• Dinner: Grilled salmon with steamed broccoli.

• Breakfast: Mirabol protein shake with spinach and almond butter.
• Lunch: Tinned tuna on a green leaf salad.
• Dinner: Baked chicken thighs with asparagus.

• Breakfast: Omelette with cheese and tomatoes.
• Lunch: Turkey burger with cucumber and gherkin salad.
• Dinner: Steak with cheese sauce and baked cauliflower.

7-day ketogenic diet:

The 7-day ketogenic diet is a meal plan designed to be followed for a whole week. It is structured so that people can follow a ketogenic diet for a short period of time, and is often used to lose weight quickly or to prepare for a specific event. During these 7 days, the guidelines of the ketogenic diet are strictly followed: carbohydrate intake is limited to less than 50 grams a day, healthy fats are preferred and moderate amounts of protein are eaten. The permitted foods and portions are carefully planned to ensure an adequate intake of nutrients while promoting ketosis.

21-day ketogenic diet:

The 21-day ketogenic diet is a longer eating programme that lasts three weeks. It is designed to be followed for a longer period than the 7-day version, allowing the body to adapt gradually to the ketogenic diet and to maximise its benefits over time. This type of diet can be useful for those who want long-term results, such as sustained weight loss, improvements in metabolic health and more energy. Over the 21 days, detailed meal plans are provided for each day, together with tips on how to handle any challenges and stay motivated.

Which supplements can be used? 

When following a ketogenic diet, it is important to pay attention not only to the foods you eat, but also to any supplements that can help maintain an optimal nutritional balance. As well as all the keto supplements now on the market, which can be added to the diet, here are some common supplements that can be useful during a ketogenic diet and the characteristics they should have:

1. Omega-3: Omega-3 supplements, such as fish oil, can be useful for maintaining a healthy balance of fatty acids in the body, especially when you eat fewer omega-3-rich foods such as oily fish.
2. Magnesium: Magnesium deficiency is common on the ketogenic diet, as some foods rich in this mineral, such as green leafy vegetables, may be eaten only in limited amounts. A magnesium supplement can help prevent muscle cramps, fatigue and other symptoms associated with magnesium deficiency.
3. Whey protein isolate: Whey protein isolate is a high-quality source of protein that contains little fat and few carbohydrates. It is ideal for anyone looking for protein supplementation without added sugars or carbohydrates.
4. Fibre: Since the ketogenic diet tends to be low in fibre, a fibre supplement such as psyllium husk or guar gum can be useful for improving gut health and preventing constipation.

Ketogenic diet: contraindications

Although the ketogenic diet can offer many health benefits, there are also some contraindications to consider. These include:

• Digestive discomfort: Some people may experience constipation or diarrhoea during the initial adaptation to the ketogenic diet.
• Nutrient deficiency: Drastically cutting carbohydrates can lead to a deficiency of fibre, vitamins and essential minerals.
• Short-term side effects: Headache, fatigue and bad breath can be common during the early stages of the ketogenic diet.

Before starting any strict diet such as the ketogenic diet, it is advisable to consult a healthcare professional to assess your suitability and discuss any potential risks.

Conclusions

The ketogenic diet can be an effective option for losing weight and improving metabolic health. With a suitable meal plan and proper supervision, many people have achieved significant results by following this eating plan. However, it is important to consider the contraindications carefully and to consult a doctor before starting.