Everything You Need to Know About the Keto Diet

With the goal of losing weight, performing better in exercise or sports, or even helping treat disorders, many people resort to this type of diet. Keep reading to learn all about the keto diet!
Everything You Need to Know About the Keto Diet

Last update: 16 April, 2020

The ketogenic diet (or keto diet) is the name for a diet that involves consuming more fats than any other macronutrient. Another characteristic of this type of diet is carbohydrate restriction. However, keep reading to learn all about the keto diet and if it’s a good option for you.

The main characteristic of this diet is that it can help your body reach a state of ketosis. As we mentioned before, this diet promotes a carbohydrate intake low enough to bring you to that state.

All about the keto diet: what is ketosis?

Ketosis is the physiological situation in which your body obtains energy through the burning of fats. First of all, keep in mind that the central nervous system cannot use fats as an energy source. In most cases, glucose is the only fuel for the brain, since fats do not cross the blood-brain barrier.

However, after two to four days of fasting or following a diet very low in carbohydrates, the central nervous system must search for an alternative energy source: ketone bodies.

What are ketone bodies?

Ketone bodies are products of the breakdown of fatty acids. These include acetoacetate, β-hydroxybutyrate, and acetone, metabolites produced in the liver in the absence of carbohydrates.

Some diseases, such as diabetes (during a drop in blood glucose), or physiological conditions, such as a ketogenic diet, can cause an increase in ketone bodies.

How to know if you’re in ketosis

A good strategy to know if you’re on the right track with your keto diet is to check the levels of ketone bodies in your urine. We know that the body is using ketone bodies as fuel when the urine concentration is 0.4-0.5 mmol/liter. The easiest way to find out the concentration of ketone bodies in urine is to use testing strips.

About the keto diet: step-by-step instructions to lose weight in 30 days

That’s the most comfortable but least accurate way to find out because as the body adjusts to ketosis, it eliminates fewer ketones in the urine. In addition, your state of hydration can affect the readings. Once your body adapts to a state of ketosis, the testing strip may not correctly indicate the true quantity of ketone bodies in your urine.

The almost foolproof way to measure ketosis is a blood test. These tests work by quantifying the most predominant ketone in the body, β-hydroxybutyrate.

Another option is to measure acetone using the breath test. Acetone that is excreted in respiration is the smallest and simplest of the ketone bodies. For low concentrations, this method can be useful.

What to know about the keto diet before starting

As you know, a ketogenic diet limits the carbohydrates you consume daily to less than 50 grams per day or less than 5 percent of the total daily calories you ingest.

Most of the macronutrients (at least 80 percent of your total calories) you consume should be fats. Likewise, your protein intake should be more or less proportional to your weight: each day, you should consume about 1 gram of protein for every kilogram you weigh. The remaining calories should be carbohydrates, however, be careful not to exceed the limits.

The main problem with this diet is that the keto-adaptation process is not immediate. You’ll need to commit to an adaptation period of at least two weeks.

More about the keto diet: foods you can eat

Reducing your carbohydrate intake to the level needed to enter a state of ketosis is not as straightforward as it sounds. These are certain types of foods you should eat that don’t typically contain carbohydrates:

  • Meats: beef, pork, lamb.
  • Poultry: chicken, turkey, duck.
  • Eggs.
  • Cheeses: cured, blue, feta. Choose cheeses that contain less than 1 gram of carbohydrate per 100 gram serving.
  • Fish and shellfish.
  • Sausages: Any kind of sausage is fine as long as they don’t contain starches or other added carbohydrates.
  • Yogurts without added sugar.
  • Maximum of 200-250 milliliters of milk per day, which is equivalent to one glass.
  • Some vegetables: Swiss chard, green olives, artichokes, celery, aubergines (eggplant), watercress, collard greens, broccoli, zucchini, etc.
  • Small portions of nuts.
  • Berries, tomatoes, and avocados.
  • Certain sweeteners: aspartame, saccharin or stevia
  • Chewing gum without sugar or mannitol.

When to follow a ketogenic diet

This type of diet can be used for weight loss, for improving athletic performance or as a complementary or additional treatment for certain medical conditions such as epilepsy.

To lose weight

People who follow a ketogenic diet tend to feel fuller and more satisfied after eating. As a result, they’re less hungry and they feel less desire to eat. Additionally, when you combined it with physical exercise and good rest, this regimen can help you to lose weight.

To improve athletic performance

In endurance sports, low carbohydrate or a ketogenic diet is optimal for improving athletic performance and post-exercise recovery. Some of the advantages are:

  • Delayed muscle fatigue, due to decreased production of lactic acid.
  • Less central fatigue, due to increased serotonin in the brain.
  • Improvement in body composition, since the keto diet favors fat loss and the maintenance of muscle mass.
  • Greater recovery speed after exercise, given the decrease in the production of free radicals.
  • Boosts insulin resistance in athletes. The blood glucose level in a state of ketosis is 90-110mg/dl (within the healthy range).
Step by step nutrition; all about the keto diet to lose weight

To improve your condition if you suffer from certain diseases

There’s evidence that following a keto diet can actually help address issues related to type 2 diabetes, polycystic ovary syndrome, metabolic syndrome, and fatty liver. Furthermore, low carbohydrate diets have been used in the treatment of neurological diseases such as epilepsy, amyotrophic lateral sclerosis (ALS or Lou Gehrig’s disease) or Parkinson’s.

To conclude, it’s important to note that this diet is of special interest to people with epilepsy. In these cases, the treatment consists of two phases: at first, patients must follow a more restrictive keto diet and reduce their carbohydrate intake to less than 20 grams.

After this first phase, patients will follow a 4:1 ratio. This means that for every 4 grams of fat in the diet, patients should consume 1 gram of protein and 1 gram of carbohydrates.

After learning all about the keto diet, maybe it sounds like a good option if you want to lose weight, improve your athletic performance, or improve your condition related to diseases you may suffer from. Be sure you speak to your physician or another qualified medical professional before starting any diet or nutrition program.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


  • Dashti, H. M., Mathew, T. C., Khadada, M., Al-Mousawi, M., Talib, H., Asfar, S. K., … & Al-Zaid, N. S. (2007). Beneficial effects of ketogenic diet in obese diabetic subjects. Molecular and cellular biochemistry, 302(1-2), 249-256.
  • Gibson, A. A., Seimon, R. V., Lee, C. M., Ayre, J., Franklin, J., Markovic, T. P., … & Sainsbury, A. (2015). Do ketogenic diets really suppress appetite? A systematic review and meta‐analysis. Obesity Reviews, 16(1), 64-76.
  • Perez-Guisado, J. (2008). Ketogenic diets and weight loss: basis and effectiveness. Archivos latinoamericanos de nutricion, 58(2), 126-131.
  • Perez-Guisado, J. (2008). Ketogenic diets: additional benefits to the weight loss and unfounded secondary effects. Archivos latinoamericanos de nutricion, 58(4), 323-329.
  • Volek, J. S., & Sharman, M. J. (2004). Cardiovascular and hormonal aspects of very‐low‐carbohydrate ketogenic diets. Obesity research, 12(S11), 115S-123S.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.