To properly understand the ketogenic diet, we must first take a look at nutritional science. Bear with me! It will all make sense 🙂
The human body uses fats and carbohydrates as its main source of energy. If both are available, they will always be used interchangeably. The availability of fats and carbohydrates depends on two things:
- The food we take
- The reserves we have built up in our body
Without wanting to offend anyone, I must say that our fat reserves are enormous! Even very skinny people have enough fat stored to last them for weeks. This is completely different for our carbohydrate reserves, which are very limited.
If we choose not to replenish our carbohydrate reserves in time (by not eating carbohydrates or fasting completely), on average we will use up our reserves after about 16 hours. The logical consequence is that our body will then be almost entirely dependent on 'burning' fats.
When the body uses fats as an energy source in the absence of carbohydrates, the fats are broken down in an alternative way.
The body will convert some of the fats into a number of molecules that we bundle under the name 'ketones'. These ketones can be used by the body to produce energy.
The ketogenic diet aims to increase the body's own production of ketones in order to achieve a state of 'ketosis'. To achieve a 'ketogenic state', carbohydrate intake should be limited to a maximum of 50 grams per day . This limited carbohydrate intake is the cornerstone of the ketogenic diet.
"Why?" is the logical question that the ketogenic diet brings. Why do we want to get into that state of ketosis, where we start using ketones as an alternative fuel? Well, it seems that ketones come with a number of benefits.
The muscles can absorb ketones into their cells without the need for insulin . Lower insulin levels are associated with a lower risk of type 2 diabetes, as well as other chronic conditions such as Alzheimer's disease.
The body learns to efficiently provide energy during times when no carbohydrates or foods are ingested. Blood sugar and energy levels also show fewer fluctuations.
- The brain can use ketones for energy in a very efficient way . People in ketosis often report higher concentration and mental clarity.
The analogy with a hybrid car is actually very apt.
Never going into ketosis is the equivalent of a hybrid car that always runs on the same type of fuel.
Recent studies such as “flipping the metabolic switch” show that it is interesting to use all our energy systems from time to time in order to achieve maximum metabolic flexibility.
In a next blog article we will go into more detail about the effective implementation of a ketogenic diet and the do's and don'ts. Stay tuned!