Ketogenic Diet 101: Definition, Types & Basics

The sum of food that we consume every day is called diet. However, the word diet often refer to taking specific nutrition for health and weight management. Though we are omnivores, our food preferences differ from culture to culture. We also witness some food taboos around the globe. Personal tastes and ethical reasons may play a role behind this. From nutrition perspective our body needs fat, protein, carbohydrates, vitamins, minerals etc. and that we get from different types of foods. Our quality of life, health and longevity highly depend on our dietary habits and preferences.

Off late, a particular diet has become crazy among celebrities and athletes as it appears to be helpful in many aspects of human health and mind.

You may be wondering about the name of this particular diet. Well, this diet is called keto diet, short for, ketogenic. Just like other fad diet, weight loss, mental clarity and increased energy are a few to mention among benefits.

So, if you get interested in keto diet and want to start it but really don’t know where to begin. Well, you just hit the right page. Honestly speaking, you probably may not get any handbook that will show you a simple way to make things done. So, in the following sections, we will give a complete guide to starting keto diet. This may become helpful to your friends and family, who are interested in starting or have already started keto diet. So you can share this page with them.

So, what is keto diet?

In the early twentieth century, doctors had done some experiment on patients to find out alternative source of fuel for body cells. Up until then, generally, carbohydrate was used as the main source to generate fuels for body cell. During the course of research, doctors came up with a different source using low carb diets. They observed that low carb diets compel the patient’s body to use fat as the primary source of fuel rather than usual glucose.

In their endeavors, they kept lowest possible glucose in patients’ body. Objective behind that action was to keep only fat in the body to burn and let that fat later turn into fatty acid. This fatty acid transforms into a new fuel molecule called ketones – which liver generated from stored fat. These ketones then disperse throughout the body, especially to the brain as an alternate fuels. This process is known as ketosis.

In a jiffy, on the ketogenic diet, to keep our body functions moving, our body cells use another source of fuels – which is ketones – in the absence of carbohydrate (glucose).

Keto diet is a process of eliminating carb from foods that we consume so that our body can generate alternate fuel source for our body cells from fat. Contrary to regular diet, it compels the body to burn fat instead of carbohydrates.

What keto diet is not: Low Crab VS Keto Diet

People have a general idea that keto diet is all about low carb diet. The fact is it’s not just a low carb diet. Basically, we can reduce carbohydrate by adapting low carb diet, but we can’t reduce them to that level where ketones can be produced. That’s why when we are on a low carb diet, fatigue and tiredness engulf us quite easily. On the contrary, keto diet makes us feel energized, brings good feelings and almost feel like ecstatic.

While Living on a Low carb diet, we feel like getting caught in a grey area. Because, a low carb diet does reduce fuel sources from carbohydrates for our body, while does not help increase fat – another fuel source – sufficiently. Therefore, low carb diet put us in middle ground where our body gets low fuel but not low enough to where body actually start using different fuel source, ketones. People have a wrong notion that keto diet is all about animal protein which stems from lots of meat and bunch of dairy. It’s a wrong perception people possess. In fact, the higher fat content that we get from keto diet is descended from good healthy plant sources.

Another issue, people take tons of expensive med getting influenced by what people say on the internet. We do not have to take any med while we are on keto diet. Besides, vegetarian or vegan can get helped by adapting keto diet.

Carb Limits In Keto Diet

Effectiveness of keto diet is set proportionately to low carb intake. The fewer we take carb, the more it becomes efficient. A keto diet is a much regimented diet and does not allow too much carb intake. A strict keto diet allows only 20 grams of net carbs per day.

Types of Keto Diets

You may get caught by surprise after reading the title, yes, keto diet is not just limited to one type.

After a thorough experiment, ketogenic diet has been divided into four methods:

The standard ketogenic diet (SKD)
High protein ketogenic diet (HPKD)
Cyclical ketogenic diet (CKD)
Targeted ketogenic diet (TKD)

Adaptation to any one of the four methods can lead us to weight loss, blood sugar stability and fat burning, but objectives and benefits of each type differ in their own.

Below, we will discuss about four approaches of keto diet more in details. These approaches allow us to take carb around our workout time, resulting improved output. The targeted group of these keto diet are heavy-duty athletes, professional bodybuilder, or trained fighters.

Standard Ketogenic Diet (SKD)

Most people are familiar with this version of keto diet. Beginners get the most out of it as it leads to drop body weight and insulin resistance. Expert suggest following dietary for SKD:

Sufficient protein intake. 0.8 grams of protein/pound of body mass
Net carb consumption per day 20-50 grams
Consumption of high fat should dominate, out of total calories approximately 68-73% from fat.

High Protein Ketogenic Diet (HPKD)

This is very akin to SKD, additionally extra protein being added. The objective of extra protein is to put a bit of muscle on our body. On HPKD, following course of action should be taken to get the macros right:

Fat should generate 60% of total calories
Protein must produce 35% of total calories
Only 5% calories emanates from carbohydrate

This method does suit bodybuilders, weightlifters, and other athletes as their body demands more protein.

You must be wondering to see high amount of protein in this diet. So, let’s find out as to whether too much protein is bad on keto diet or not.

We possess a wrong notion that taking excessive protein affects us negatively and slow down our ketosis process. As a result, after sometime we get back to the point where we all started – losing ketosis state. All these happen only because of gluconeogenesis (GNG). GNG is the process of producing glucose from nutrients other than carbs. In this process our body can’t make glucose from other nutrients as fast as the way carbohydrates does. GNG has been termed as very steady process.

An example will make this clearer. Eating chocolate cake leads to increase our blood glucose within a small amount of time in response to sugar lies with it. Whereas, our blood glucose does not increase at the same rate when we take extra protein because of steady characteristics of GNG.

Cyclical Ketogenic Diet (CKD)

Interestingly, this diet allows eating high carb diet, but in phases. This diet is all about changing our diet in two stages: standard ketogenic diet stage with carb filling stage. Duration of high carb phase can last for a day or two. In this phase, approx 70% of our calories should emanate from carbohydrate.

In a week, our diet should resemble following:

Standard ketogenic diet phase (first five days):

70–75% of calories from fat
20–25% of calories from protein
5% of calories from carbohydrates

Carb-loading phase (following two days):

carbohydrates should responsible for 70% of total calories
20–25% of calories should stem from protein
Fat should generate 5–10% of total calories

Bodybuilders get benefited most out of this diet and also helpful for athlete who wants to build lean mass by losing fat.

Targeted Ketogenic Diet (TKD)

This diet allows our body to take carbohydrates proportionately to our workout. This diet does help maintain exercise performance as it supplies glycogen to our muscles and energizes it during exercise.

In this diet approach, we should load carb before an hour exercise. And the ideal amount of net carbs would be 20-25 grams for the day. TKD is such a diet that blend the standard ketogenic diet and the cyclical ketogenic diet. It allows gymnast who likes to work out focusing on enhancing body strength. TKD also helps us stay on ketosis for a long period of time.

Keto Basics: What are Keto, Ketosis and Ketoacedosis

Keto

The word ‘keto’ originates from the term ketogenic or ketosis. People sometimes get scared when they confuse it with ketoacidosis – which is bad for our body. While adapting keto diet, we enter into the lifestyle of low carb foods. This regime allows only 20-25 gram carbs intake per day.

When we are on keto diet, our body uses ketone – produced from fat – as an alternative fuel source instead of sugar and carbs.

A keto diet is a special kind of diet that help burn fat more effectively as it contains low carbohydrate, high fat and medium protein.

Ketosis

Ketosis is a metabolic state of the body, when it is nearly completely powered by fat. Normally, ketosis tends to happen when the body is absorbing fat at a higher rate and transforming fatty acids into ketones. There are two main ketone bodies that produce energy for our body: acetoacetate and β-hydroxybutyrate.

Fasting and maintaining low carb diet may help us achieve long-term ketosis. Expert terms ketosis as normal physiological process and have not found any risk associated with this dietary. Our body attain a metabolic state called ketosis, when it produces ketones.

The fastest way to acquire this ketosis state is by fasting. However, nobody can fast for indefinite period of time. On the contrary, one can live on keto diet forever and can attain the ketosis. Besides, it can provide us with all the benefits of fasting, without having to fast. “it’s a simple dietary that keep our body in ketosis state all the time without really fasting“ says Gillian McKeith, a famous nutritionist.

Ketoacedosis

Ketoacidosis is a condition stems from dangerously high levels of ketones and blood sugar. This combination paves the way for our blood to become acidic, which can prompt malfunctioning of some of our important internal organs like liver and kidneys. During ketoacidosis, kidneys tend to start emitting ketones bodies along with body water in the urine.

It can occur within a short period of time, even within 24 hours. The victim of the ketoacidosis are the people with type 1 diabetes as their body cannot produce insulin. The main causes that trigger ketoacidosis are illness, improper diet or taking lack of insulin dose. Insulin is a hormone that helps avert overproduction of ketones.

Ketosis Vs Ketoacidosis

Another important issue, people often get confused with the terms ketosis and ketoacidosis. These two terms stands for two completely different meanings. We have already discussed in details what ketosis is all about whereas Ketoacidosis is a diabetic complication where the body produces excess ketones. Ketoacidosis is something that associated with type 1 diabetic as they do not have insulin. Because of absence of insulin, their blood can produce high level of ketones causing ketoacidosis. The level of ketones are much higher in this state compared to what we get in the nutrition state of ketosis.

Types of Ketones

Fatty acid forms into three ketones when broken down:

Acetoacetate (AcAc): created first during ketosis
Beta-hydroxybutyric acid (BHB): formed from acetoacetate
Acetone: by product of acetoacetate

Acetoacetate — First Ketone

Benefits of ketones may not have come into fore without acetoacetate. In fact, it helps formed other two ketones bodies – acetone and beta-hydroxybutyrate (BHB).

This ketone sets the tone for our body to use alternate energy more efficiently when we go for low carb intake. However, it can’t run the process solely, it needs the help of its other counterparts.

For us, glucose being considered as the primary source of energy. By default, our body uses glucose for energy. Hence, our body burns glucose out quickly and also replenish it fast from our food.

Carbs – when we digest – immediately turns into glucose for our body to use or stored in our muscles, brains and liver as glycogen 3.

When we limit our carb intake, meaning when are fasting or on keto diet, our body will trigger automatically two metabolic process to cover up the slack. First, fat will be used to generate alternate fuel source for body cell and secondly, the liver will speed up a process called ketogenesis.

During ketogenesis, fatty acids (and some amino acids) are converted into ketones by using liver. To be concise, two acetyl-coas – molecules that shuttle energy metabolism –mingle together to form the acetoacetate, first ketone body.

One of the following three results will be realized, when acetoacetate formed:

Acetoacetate will be dispersed to other cells to use as fuel.
It will be turned into a energy efficient ketone body called BHB and scatter energy throughout the body.
this ketone body will spontaneously pave the way to create acetone.

Beta-Hydroxybutyrate (BHB)

Beta-hydroxybutyrate (BHB), is another ketone bodies that our liver makes when we choose to live on a low carb diet.

In our body, this ketone dominates as far as quantity is concerned. Typically, this ketone body making up 70 ~ 80% of ketones found in the blood. As we mentioned earlier, both BHB and acetone are the byproduct of acetoacetate. However, for energy generation our body mostly use BHB as it’s extremely stable and abundant, whereas acetone disappears through respiration and sweat.

Only BHB can play the role of an alternative fuel that most of our brain cells can use to swap sugar. Usage of BHB allows our body to preserve muscle mass and experience several health benefits.

Acetone

One thing we would get in common in our nail polish eraser and blood is acetone. Surprised! Yeah a very people know about this fact.

Acetone, systematically named propane, considered as the simplest and smallest ketone. Acetone production in our body is natural as our body get started to burn fat rather than carbohydrate as an alternate source – this process is known as ketosis. And achieving ketosis is the main purpose behind embracing keto diet.

However, excessive acetone production can be harmful and can trigger side-effects. Our body emits unnecessary acetone through sweat which may cause keto rash.

If we inhale or ingest acetone from outside environment, we might get poisoned. However, when it is produced within our body it deems as innocuous. Sometimes, it helps in many functionaries working as a catalyst.

Natural source of acetone are aplenty and we can find them in our flora and faunas, in livestock, and in our surrounding environment. Acetone is famous for an active ingredient in painting, polishing and other industries it mixes with other solutions very effectively.

The purpose of ketones: Why start ketogenic diet?

So far we have learned the simple mechanism behind ketone production. However, one question is still left unanswered: why so much precious energy being wasted while producing ketones, if it can just burn fat?

After conducting too many research on ketones, experts have come to know the purpose of ketogenesis: creating fuel for the brain in the absence of sugar.

This is imperative as most of our brain cells cannot use fatty acids for fuels. Energy that brain needs is huge and has to be replenished almost immediately. But, our body’s fat metabolism process is too slow to keep up the pace with brains energy needs. (and a risk of too much muscle wasting lies with protein to sugar conversion process by using gluconeogenesis).

So, ketones came up with a better solution. These small, water-soluble molecules quite easily travel through the blood and cross the blood-brain barrier, working as efficient energy shuttle. However, fat cannot serve the same purpose, except for some medium chain triglycerides.

Ketones work as a quick energy source, once they enter into the brain. Whereas, sugar is also an energy source for the brain but not as efficient like ketones. As a result, less free radicals and responsive oxygen species being gathered by cells. Hence, barring the brain from cell damage and mental impairment.

3 Major Keto Diet’s Mechanism: How keto diet works?

When we start keto diet and literally limit our carb intake, glucose levels in our blood drop. Then our body starts to use liver glycogen (stored glucose) in order to elevate blood sugar. Besides, due to absence of adequate carbs our insulin levels drop. This reduction in insulin stimulates fatty acids to breakdown and also cause disruption to supply of fatty acids to liver mitochondria. Next, liver starts producing ketones to satiate body’s rising energy demands. However, most of the ketones will be consumed by our brain as it controls all body functions. Therefore, it needs constant supply of fuel. This fuel producing process is articulated in more detail below.

Fat Adaptation

Living on a keto diet for a certain period of time helps our body get used to using fat as a fuel source. Meaning we do not have to live on keto forever, if we continue it for a definite time, as our body gain the capacity to use fat as a fuel source. It’s a development expert like to reference it as mitochondrial machinery. In our body mitochondria create energy for our cells. But when we are on keto diet, that mitochondria gather the ability to use fat for fuel. Whereas it does not happen with regular diet. That is why it is called fat adaptation. When we become fat adapted, our body – under any condition – prefer to use fat as a fuel source when readily available.

Now, the question that revolving around your mind is how long it takes to get to that adaptation. Studies suggest that it takes no longer than six weeks. That means six weeks are enough for our body to make that shift from starting point of keto diet. Interesting thing in this process is that our body acquires such ability that it uses ketones for some cells. Simultaneously, uses straight fat for some other cells like muscle cells and still miraculously uses glucose for other cells. So, that means our body never stops producing carbohydrates. They always exist in our body naturally and they never become null & void. Therefore, our blood sugar never reach the level of zero.

You may wonder as to how our body produces those carb when we reach ketosis state. Actually, we get those carb from protein and small amount of carbs that we consume daily basis. Therefore, we can’t get rid of carbs as it is important for some of our body cells. So, when we reach the ketosis state, as a fuel source, our body uses fat along with natural carbohydrates. Meaning our body can use all kinds of fuels to keep it functional properly. It’s like having a vehicle that can run on diesel, jet fuel and gasoline.

Boosting brain

Our brain is the epicenter of our body and thus controls all the activities of our body. Therefore, our brain does consumes a lot of energy to keep it functional 6. Especially when it comes to diet, it’s more of a mental thing.

Ketogenic diet does create some interesting things with the body. Usually, our body thrives on glucose. But when we adopt keto diet, we dip into ketosis and that leads our body to produce ketone bodies. One particular ketones called beta-hydroxybutyrate crafts an interesting effect on brain. This specific ketones creates extra energy within glucose on per unit of oxygen. That implies that this beta-hydroxybutyrate ketone can help accelerate our brain power. And consequently, makes us feel good and induces our inner joy, when our body flourishes on ketosis 7.

Another aspect of keto diet is its positive effect of mitochondria in the brain. In 2004, a study was conducted on two groups: one on a regular diet and another on keto diet for an extended period of time. Later the study came up with the result that the group on keto diet showed ketosis does put an influence on the gene expression of their brain, especially on memory and focus portion of the brain.

In concise, keto diet – if we continue for long period – does help our brain to grow or expand a little bit. Which means we can get more energy, more blood flow and more effectiveness out of the memory and focus part of the brain.

Muscle sparing effect

Some people believe that keto diet leads to a bunch of muscle reduction, which is absolutely not. A study published in The Journal of Clinical Investigation that came up with the theory that existence of ketones in the blood decrease loosen oxidation 9. Therefore, muscle protein of body does not break down that much, when we live on keto diet.

Another thing, people have been asking questions about sustainability of preserving our muscles with keto diet. There is a term associated with keto diet called resting metabolic rate meaning how fast we lose our metabolism. Normally, it is known that our metabolism decreases when we lose weight.

However, a study published in The American Journal Of Nutritional Metabolism that found our resting metabolic rate remains the same, it does not decrease, when we lose weight adapting keto diet. Because ketones does help preserve our muscles and that later burns a lot of fat.

Effectiveness: Ketones VS Glucose

After reading the above mentioned all those technical terms, a question that may come to your mind which is more effective: body runs on fat or runs on glucose. To be honest there is no specific answer to this question as it depends on your activity. If you consume food that is high on Carb usually contains about 4 calories/gram whereas food that is full of fat contains about 9 calories/gram. This data may trigger you to think that way too many calories coming in from fat which leads to weight gain. It’s one way to look at it. But from a different angle, from energy viewpoint, if we truly conditioned to run our body on fat, then it can generate more energy per gram for us rather than focusing on calories.

Even, we may satiate our appetite with eating less, while getting more energy throughout the day. But, we really failed to feel the difference as fat satiate us and arrest our hungry feelings.

Medical adaptation of keto diet

In the 19th century, keto diet was tried to help control diabetic. In the early 20th century, experts started using it as medicine for children to treat hard to control epilepsy. Moreover, keto diet has been tested and used in a controlled setting for cancer, polycystic ovary syndrome, and Alzheimer’s disease.

Now a day, people are giving considerable thought on this diet as potential weight loss strategy. However, atkin diet (a low carb but high protein diet) played a big role behind this theory as it was a commercial success and help popularized low carb diet to another level. In contrast, keto diet is contains distinctively high fat, typically 70% to 80%, though it depends on low intake of protein.

Another benefits that derives from ketogenic diet are:

Better mood
Sound sleep
Satiety
Mental clarity
Better skin

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