The Benefits of The Ketogenic Diet Myths and Truths

Today, the ketogenic diet has become popular as a weight loss diet. Even in the sports field, it has also been gaining prominence for its supposed advantages. However, many of the benefits that have been associated with the keto diet are nothing more than myths. Throughout this article, we will show what is true about the benefits that have been associated with the ketogenic diet. However, we have already anticipated that there are no guidelines based on scientific evidence that support its efficacy and long-term safety.

What is the ketogenic diet?

The ketogenic diet is one that provides around 20-50g a day of absorbable carbohydrates. Thus, carbohydrates constitute only 5-10% of total caloric value. Fats contribute between 65-80% and proteins between 20-25%. The foods used are usually oil, some vegetables (especially leafy), fish, meat and eggs. However, this type of diet excludes healthy foods such as legumes, fruit, nuts, whole grain farinaceous and tubers. So you can get an idea: a medium potato provides about 30g of carbohydrates. Considering carbohydrate restriction, potato is prohibited in the ketogenic diet.

How and when did the ketogenic diet appear?

The ketogenic diet was first used at the Mayo Clinic in 1921. It was first used to treat children with severe epilepsy, since fasting had been shown to work positively in reducing epilepsy episodes. Episodes decreased with decreasing glucose and insulin values ​​and with increasing production of ketone bodies.

What happens in our body when we follow a ketogenic diet

By following a ketogenic diet, blood glucose levels are kept to a minimum, as if we would be on an extended fast. This causes the pancreas to secrete too little insulin and the cells of our body have to use fats and proteins as an energy source. The result of the latter is an increase in the concentration of ketone bodies or ketones in the blood.

The first symptoms that can be experienced when this occurs are: headache, dizziness, vomiting, halitosis, general weakness, cramps, and changes in bowel frequency. In general, these symptoms may decrease over the days.

Usually, with less than 40g a day of carbohydrates, ketone bodies could already be observed in the urine. However, the most restrictive advocates advise consuming less than 20g of carbohydrates a day. In this way, the appearance of ketones in urine is achieved and their control is recommended through the use of test strips.

What about body weight?

In relation to body weight, it usually decreases progressively. This decrease in weight is due to three reasons:

1. Muscle glycogen (carbohydrate) is quickly consumed. This entrains water, since they are together in a ratio of approximately 1: 4g. So, if we have 300g of muscle glycogen and lose it, we drag an additional 1200g of water.

2. Production of ketone bodies or ketones from the liver and fat metabolism. These ketone bodies are eliminated by respiration and, especially, by urine. This also increases fluid loss.

3. Protein mobilization as an energy source. For this reason, if a contribution of 1g of protein per kg of weight is not guaranteed, the loss of muscle mass will be accelerated. There are even people who need a daily intake of 150g of protein to achieve an acceptable nitrogen balance.

What is the difference between ketosis and ketoacidosis?

Ketosis is the increase of ketone bodies in blood until reaching a ratio of 3.0mmol / L. Ketoacidosis occurs from 6.0 mmol / L. The risk of ketoacidosis in a healthy person is rather low. However, in people with diabetes, especially type 1, it is recommended to go to the emergency department if they have more than 3.0mmol / L because there is a risk of ketoacidosis and coma.

In a healthy person, an excess of ketone bodies activates the production of insulin. This blocks the metabolism of fats and the production of ketone bodies. Then, the elimination of ketones in urine increases so that the blood pH does not continue to drop. Insulin also activates the neoglycogenesis process in the liver. This process involves the production of glucose from amino acids and fats. Since the body can produce some glucose through other substrates such as protein, increasing dietary protein intake can also lead to ketosis. There would be virtually no impact on blood glucose.

What about micronutrients?

Urine excretion of minerals in a ketogenic diet is increased. For this reason, an additional intake of about 3-5g of sodium, 1g of potassium and 300mg of magnesium is required. In addition, there are also other nutrients that could be affected. Some are: calcium, vitamin D, selenium, magnesium, zinc and phosphorous. In the long term, this can affect bone health, immunity, and other metabolic processes.

Sides, adverse effects and possible benefits of the ketogenic diet

Within the ketogenic diet, there are different versions. One is the Atkins diet, with protein-free consumption. There is also one aspect of the ketogenic diet with increased consumption of medium chain triglycerides and another with a low glycemic index. The ketogenic diet is also used in cases of children with refractory epilepsy. In the latter case, it is allowed to increase carbohydrates up to 60g daily. This is because an extreme keto diet can also affect growth. In addition, it can also cause headache, dizziness, nausea, weakness and changes at the intestinal level. In any case, this type of diet requires specific and continuous advice from trained health professionals.

Currently, the effects that this type of diet can have on pathologies such as obesity, diabetes, cardiovascular diseases, polycystic ovary syndrome and even cancer and neurological diseases are still being investigated. This is so because there is a decrease in insulin and triglyceride resistance when the keto diet is followed. However, it is also correlated with an increase in total cholesterol, especially LDL, which is deposited in the arteries.

Ketogenic diet and obesity

In relation to obesity, scientific evidence makes it clear that the key is the acquisition of good physical activity habits and a balanced diet. The ketogenic diet is not related to this main objective. In addition, as we have already discussed, it can produce several adverse effects. To this must be added that, being so restrictive, it is difficult to achieve and the long-term weight loss is not superior to that achieved with a low calorie diet. In other words, in the long term, it does not have safety or proven efficacy.

But ... does it help lose fat?

The key to lowering body fat is not in such restrictive diets. The important thing to lose body fat is: boost the consumption of foods of plant origin such as legumes, tubers, nuts, etc., and decrease the consumption of ultra-processed foods rich in sugars, salt and low-quality fats. Learning to plan healthy menus and use the right portions is also key. In this way, the correct caloric deficit will be achieved that will lead to the desired decrease in body fat. Personalizing food and changing eating habits and physical activity are essential. Not only to advance towards the goal but also to maintain the long-term result.

In what situations is the ketogenic diet contraindicated?

The ketogenic diet is potentially contraindicated in people with APO-E4 gene alterations, people with arrhythmias, osteoporosis, kidney problems, people with high cortisol, chronic constipation or problems with the intestinal microbiota. It is also not recommended in people with diabetes who cannot control their blood glucose continuously, among other pathologies.