Ketogenic diet: What is, benefits and meal plans

Ketogenic diet

Surely this article is going to sow doubts or you are going to think that the author is crazy. The reason, what I am going to try to explain to you below is going to break with practically everything you have heard about fitness nutrition. It is a fairly extensive topic so I am going to divide it into several parts because I would not want to leave anything out that could lead to confusion or end up creating misinformation.

Before explaining in detail what a ketogenic diet consists of, let’s briefly review what the current diet is based on. I’m pretty sure you’ve heard that glucose is your body’s preferred source of energy, that you need to be constantly recharging your blood glucose levels so you don’t faint by ingesting certain amounts of carbohydrates every few hours in order to eat 5 or 6 meals a day. This means that without being conscious you are constantly making your body work, which can cause metabolic stress, constant hunger, insulin spikes, fatigue… but why?

Our body is limited in terms of glycogen stores, i.e. stored glucose. When carbohydrate refueling takes place, the body increases insulin in order to dispose of the excess glucose through the bloodstream to compensate for the levels. Too much glucose is harmful and this can lead to serious health problems.

Why constant hunger and fatigue? Because your body, being used to obtain energy from glucose and having limited reserves, will demand more glucose to “function”. Hence the feeling of constant hunger and lack of energy.

As you can deduce all these processes cause constant stress to your body, it is continually forced to perform a series of processes to obtain energy.

The first conclusion we can draw is that if we are regularly drawing energy from our glycogen stores and recharging them, our body will not only not use the stored fat reserves, but the unused carbohydrates will be stored as fat.

If we focus solely on the aesthetic point (in my opinion health should always prevail over aesthetics), we will need to consume far fewer calories than necessary according to our daily caloric expenditure for fat reserves to be affected.

Carbohydrate consumption

Ketogenic diet

It is not my intention to demonize the consumption of carbohydrates. If the intake of these is adequate and especially if they are complex versus simple there should be no problem. To understand this, let’s look at the differences between simple and complex carbohydrates:

Simple carbohydrates

These are sugars with a chemical structure composed of one or two sugars. These are broken down by the body quickly to obtain energy, they can be found naturally in foods such as fruits and milk or unnaturally, ie processed and refined foods such as sweets, jams, flour, pasta, cookies, industrial juices, table sugar, sugary soft drinks, etc … These carbohydrates have very little nutritional value so it is advisable to limit their consumption.

Complex carbohydrates

They are sugars with a chemical structure of 3 or more sugars, linked together forming a chain. They are rich in vitamins, fiber and minerals, for this reason the body needs more time to assimilate these carbohydrates, so they do not increase sugar levels (insulin peaks) in blood as quickly as simple carbohydrates. Vegetables are the foods where these types of carbohydrates are commonly found.

I may have extended a little more than necessary but as I said at the beginning I think it is necessary to explain even briefly some basic concepts to better understand the differences between a “traditional” diet or a ketogenic diet, although I like to see it as a way or lifestyle rather than a diet.

What is ketosis

It is the state in which the body is able to use fat or its reserves as a source of energy. To achieve this state it is necessary that our glycogen stores are empty. How is this achieved? By means of a low carbohydrate diet or temporary/intermittent fasting.

This involves a period of adaptation, from one day to another your body will not be able to generate ketone bodies and therefore you will not notice its benefits immediately, which I will detail later.

We have mentioned that glucose reserves are limited, that the body cannot store it. But this does not happen with fat, in case of an excess of it our body stores it for later use. This should give us to understand that the human being is designed to function with fatty acids as the main source of energy.

If we look at it from an evolutionary point of view, humans initially fed mainly on game and food that they could gather above ground (hunter-gatherer), as long as they did not live in cold areas. This was the case until we became farmers, at which point humans began to consume carbohydrates on a regular basis.

The consequence of this is that if our purpose is to be in ketosis we must re-educate our body to start using fat as the main source of energy and use the stored reserves more easily. For this reason ketosis is highly recommended for definition phases, it is extraordinarily effective.

Fat as a source of energy? Really?

This may sound strange to you, but the body can obtain energy from fatty acids. This is due to the creation of ketone bodies in the liver in response to low glucose levels and after depletion of glycogen stores, but what are ketone bodies? They are molecules derived from fat oxidation that are highly energetic and much more efficient than glucose as an energy source.

To be successful we must restrict the consumption of net carbohydrates to less than 50 grams per day, it should be noted that the 50 grams that we must record are net, this means that we must subtract the fiber values of the foods we consume. It is advisable that the main source of carbohydrates are vegetables, since you will be able to consume a large amount of them without exceeding the recommended 50 grams. Although carbohydrates are found naturally in vegetables, most of them are recommended for their high fiber content.

Benefits of ketogenic diet

Improves the lipid profile, because although it increases the total cholesterol level and HDL, it decreases triglyceride levels, so the result is the following; the lower the triglycerides and the higher the HDL, the lower the cardiovascular risk.
Greater feeling of satiety since the digestion of proteins and fat is slower.
Reduces blood sugar levels, thus improving glucose control in diabetics.
It is used as a treatment for epilepsy in children and is being tested against diseases such as Alzheimer and Parkinson. It is also being used as a complement to chemotherapy in cancer treatments.
It promotes fat loss by protecting muscle mass.
It improves your brain health.
It will improve your metabolic flexibility.

To successfully carry out a keto diet, we must take into account that the first thing we must do is to eat natural or unprocessed products, always avoiding processed foods as much as possible.

Foods could be classified into 3 groups, one would be unprocessed foods and the other would be processed foods, which we would divide into 2 groups.

Unprocessed food group: as can be deduced, they consist of foods that come from nature and have not been processed by industry.

Processed food group (raw material): these are ingredients that are extracted from other foods and are subsequently used to manufacture other foods in the following group. An example would be vegetable oils, sugars, starches, flours, etc.

Processed foods group: these would be processed foods themselves and could in turn be divided into two subgroups.

  • Canned: these are foods that have not been modified, only preservatives are added.
  • Ultra-processed: this means that they are foods that have been created with the foods of the 2nd group. For example: ice cream, potato chips, breads, pastries, carbonated beverages…

Foods to prioritize and which to avoid on ketogenic diet

This diet is not strict but it is restrictive, you have a lot of foods that you can consume but you must take into account which ones to avoid. Remember the limit of 50gr net carbohydrates per day.

Food to eat?

Meat of all kinds, whether it is a product of livestock or hunting. Preferably organic, but if the economy does not allow it, do not worry, just make sure you buy natural food, breasts, fillets, loin, etc…
Fish and seafood, to prioritize fatty fish such as salmon, sardines, trout…
Vegetables, possibly at this point is where more doubts may arise. Preferably consume vegetables that grow above the surface of the earth, such as all variants of cauliflower, spinach, zucchini, tomatoes, eggplant, avocado, etc…
Eggs, in all the forms you can. Eggs are a superfood par excellence, the best source of natural protein.
Oils, prioritize the consumption of coconut and olive oil. Butter is also a good option for cooking, controlling quantities as it is highly caloric.
Nuts, walnuts and almonds would possibly be the best options due to their high content of omega 3, calcium in the case of walnuts and magnesium, fiber, protein in the case of almonds.
Dairy products, yogurts and cheeses, preferably with high fat content, lose the fear of them.
Drinks, mainly water, but it is also advisable to drink coffee and/or tea.

What foods should you avoid or limit your consumption?

Avoid sugar, cookies, pastries, cereals, processed foods, sugary drinks, etc…
Starch. Here we refer to bread, rice, potatoes, oatmeal, quinoa, pasta, cassava…
Fruit, this type of food contains a lot of sugar in its natural form, fructose.
Vegetables high in carbohydrates: corn, leek, onion…

Ketogenic food pyramid


As I explained above, if we want to follow a keto diet and use fats as a source of energy, we need to re-educate our body and this involves an adaptation period of approximately 4 weeks.

When we stop consuming sugar, our body will experience a “sugar detoxification” in the case of noticing any of the following symptoms it will be within the first week in general, they are mild symptoms and easily solvable by following a series of guidelines.

Some potential discomforts of ketogenic diet

Increased urination. By not ingesting carbohydrates your body will convert your glycogen stores into glucose and in this process water is released.
Strange breath. Your body by producing ketone bodies may have an excess of these, which are eliminated through urine and/or breathing, which in some people can mean having a stronger breath.

The first time you consider following a keto diet, you will be eating real food. That is, you will not be eating processed foods, so you will not be reaching the necessary levels of sodium. For this reason you need to include 4-5 grams of salt daily in your meals, your body needs electrolytes to function properly.

In addition to sodium levels you should take into account the levels of magnesium and potassium. To keep them under control, it is recommended to include a serving of vegetables at every meal and to include avocados in your diet on a regular basis. As always, it is important to drink water throughout the day.

Taking this into account, you will have solved most of the discomforts in case you could suffer from any.

Not everyone has to notice these symptoms, you may not even suffer from any, but it is better to be forewarned.

During the first week you will notice a considerable weight loss (1kg extra), this is due to all the fluid that is lost during the first days of adaptation if you are following the premise of consuming 50gr net carbohydrates per day.

As you can see, carrying out this type of diet requires some knowledge of nutrition and cannot be planned lightly, so if in doubt, I recommend that you consult a specialized nutritionist in your area.

If you want to perform a period of ketosis simply out of curiosity or because you want to see if it really is so effective in times of definition among other benefits, I detail what could be a menu for a week following the guidelines for this type of “diet” that is very low in carbohydrates, moderate in protein and high in fat.

Since eating (healthy) fats gives us a great feeling of satiety, I think it’s best to plan 2 or 3 meals a day, in this example I’m going to use 3 meals to make it more affordable for everyone. If you are familiar with intermittent fasting, great you can go down to 2 or even 1 meal a day (known as OMAD [One Meal a Day] protocol), depending on your training.

Sample weekly ketogenic diet menu


Breakfast: avocado salad with tuna and homemade mayonnaise.
Lunch: Spicy hamburgers with sauerkraut and homemade mayonnaise.
Dinner: “keto pizza” (e.g., with almond flour) of egg whites with ham and brie cheese.


Breakfast: spinach with veal, brie cheese and walnuts.
Lunch: Eggplant omelet with mushrooms and parmesan.
Dinner: Zucchini and carrot noodles with avocado pesto.


Breakfast: Scrambled eggs, with sautéed vegetables, mushrooms and minced meat.
Lunch: Zucchini and carrot noodles with avocado pesto. Two-egg omelet with tuna.
Dinner: Cloud bread with bacon and green beans.


Breakfast: Avocado with tuna and anchovies. 2 egg omelet with cheese.
Lunch: Kale with veal, walnuts and brie cheese.
Dinner: Cauliflower pizza with salmon and blue cheese.


Breakfast: Wild asparagus with veal and mushrooms.
Lunch: Avocado with egg, ham and baked cheese.
Dinner: Chicken breast with coconut milk sauce.


Breakfast: Bacon with eggs and salad of lamb’s lettuce and arugula.
Lunch: Tartar with salmon and cod.
Dinner: Meatloaf with cauliflower.


Breakfast: Omelet with spinach, walnuts and brie cheese.
Lunch: False Rissoto of cauliflower with mushrooms and ham.
Dinner: Trout with ham and cheese with Brussels sprouts garnish.

As you can see the ideal is to try to include vegetables in each meal to have controlled levels of micronutrients necessary for the proper functioning of our body. Always controlling quantities so as not to exceed the premise of 25gr net carbohydrates per day.


Prepare several portions of each meal is not a bad idea, because if you do not mind repeating meals on consecutive days or alternating days, you will save a lot of time in the kitchen. This time you save can be invested in training tricks that you have pending.

I also think it is important that you are constantly looking for new recipes or innovate on your own if you like to try new things. One of the biggest problems when planning a diet lies in the simplicity of the menus. If you always resort to the same dishes, you will usually end up getting tired of them.

At first, record everything you eat in an application dedicated to recording and accounting macros such as FatSecret or MyFitnessPal. This can be the difference between going into ketosis or not and getting the results you want, muscle gain, definition or maintenance.

Possibly among all the recipes that I propose in the menu, perhaps the ones that have caught your attention the most are the cloud bread or the egg white “pizza”. Since by name they may not seem to be the most recommended to follow a Keto diet. So I show you these two recipes to prove that you do not need great culinary skills to make different and surprising dishes.

Recipes for ketogenic diet

Cloud bread

Ketogenic diet


3 Eggs.
150 gr Cheese spread.
1/4 teaspoon of baking soda.
Optional: salt, pepper, spices to taste

Instructions to follow:

Heat the oven to 150ºC.
Separate the egg whites from the yolks. Here everyone can use the system that works best for them. In my case the first time I tried with a plastic bottle and it was a disaster, so if you have a little skill with the same eggshell you can separate them.
Beat the egg yolks with the cheese and set aside in a bowl.
In another bowl beat the egg whites with the baking soda until stiff.
Add the yolks and cheese mixture to the egg whites, stirring slowly with a spatula, as we do not want to lose the texture of the stiff peaks.
Place parchment paper on a baking sheet and spread the mixture. To make them as round as possible, I used a metal cooking ring.
Optional, not to make all the portions the same and to give it a personal touch, you can pour over the spice mixture that you like. I used garlic powder and oregano in some, salt and pepper in others, curry and turmeric, hot paprika… You can even add chia seeds, sesame seeds, pumpkin seeds… This just occurred to me, so I have to try it the next time I make it? The only condition is that what you add are dry ingredients so as not to alter the texture of the bread.
Bake in the oven for 20 minutes at 150ºC.

Distribution of total macros (9 units):

Total calories: 290 kcal.
Proteins: 13 gr.
Fat: 24 gr.
Carbohydrates: 4 gr.

Breakdown of macros per unit:

Total calories: 32 kcal.
Proteins: 1,5 gr.
Fat: 2,6 gr.
Carbohydrates: 0,5 gr.

Pizza with egg white base

Ketogenic diet


8 egg whites or 250gr if you use canned eggs.
Various spices: basil, pepper, oregano…
75gr of ham.
50gr of brie cheese.
50gr of mushrooms.


The most important thing to obtain a base as similar as possible to a pizza is to put the frying pan over medium heat, then pour the egg whites and keep over medium heat while pouring the rest of the ingredients on top. While the ingredients on the top are being cooked, the base curdles and toasts. Leave everything in the frying pan for about 10 minutes or until the borden is golden brown.

Distribution of total macros:

Calories: 483kcal.
Proteins: 61gr.
Carbohydrates: 3gr.
Fat: 24gr.