Keto diet

April 20, 2024

Is the ketogenic diet or Keto the long-awaited way to lose weight effortlessly, and improve athletic performance, well-being and overall health?

What is the Keto diet and what is the pseudo Keto diet?

Only a diet that causes an increase in blood levels of ketone bodies to 0.5-3 millimoles per litre can be called a Keto or ketogenic diet. Since the adherents of all kinds of pseudo-keto diets, pills, etc. do not control their blood ketone levels – they probably just think they are following a keto diet, but in reality, they are spending their money on something else.

The keto diet is a very low-carbohydrate diet that involves a restricted intake of carbohydrates (up to 5% of the total daily calorie intake), normal protein intake and increased fat intake, resulting in a metabolic state called ketosis – where the body instead of glucose uses the fat in the body and from the diet for energy.

Types of keto diets

Ketosis can be achieved in various ways and there are therefore several variations or types of ketogenic diets. Each has its specific guidelines and goals.

Here are the most common variations of the ketogenic diet:

Standard Keto Diet. This is the most popular version of the ketogenic diet and the one that has been most studied. The standard ketogenic diet is very low in carbohydrates (about 5-10% of total calorie intake), moderate in protein (about 20% of total calorie intake) and high in fat (about 70-75% of total calorie intake).
Targeted ketogenic diet. This variation of the diet is mainly recommended for athletes. The diet allows the intake of additional easily digestible carbohydrates (e.g. glucose or foods with a high glycaemic index) to provide energy during intense exercise. Carbohydrate intake should be 30-45 minutes before training or competition and just enough to achieve/maintain ketosis after training with a conventional ketogenic diet.
Cyclic ketogenic diet. Although looking at the many “Keto friendly” recipes available on the Internet may make it seem like Keto is an easy diet to follow, it’s actually not, mainly because of the many unpleasant side effects. This is why some people cycle back to a higher carbohydrate diet. For example, a strict ketogenic diet is followed for 5-6 days, then 1-2 days where the carbohydrate intake is significantly increased.
High protein ketogenic diet. While the standard ketogenic diet emphasises moderate protein intake, some variants increase protein intake to around 30-35% of total calories, while reducing fat intake to 60-65%. Carbohydrate intake remains constant at 5% of daily calorie intake. This version of the ketogenic diet may be suitable for people who need more protein to maintain muscle.
The modified Atkins diet is a less restrictive version of the ketogenic diet that allows a higher protein and carbohydrate intake than the traditional ketogenic diet. It usually limits carbohydrate intake to about 10-20 grams per day but does not limit protein intake. 20 g of carbohydrates per day may be too much to put the body into ketosis, so this variation is suitable for those who want to follow a modern diet but do not want to face the difficulties and side effects of ketosis.
Vegetarian or vegan ketogenic diet. This variation of the ketogenic diet is for those following a vegetarian or vegan lifestyle and focuses on plant sources of fat and protein (tofu, tempeh, nuts, seeds and vegetable oils).
MCT ketogenic diet. This version of the ketogenic diet involves a higher intake of medium-chain triglycerides (e.g. coconut oil), which are rapidly converted to ketone bodies by the liver. This may help to raise ketone levels more quickly, potentially increasing the benefits of ketosis.

How does the Keto diet work?

On a normal varied diet with carbohydrates providing up to 60% of daily energy needs, the body gets almost all of its energy from glucose, the end product of carbohydrate breakdown.

The cellular energy systems of all organs are adapted to work with glucose, which easily and quickly supplies cells with the energy they need. Still, some organs can get energy only from glucose – for example, the liver.

But.

If your blood glucose levels drop, for example – you haven’t eaten for a long time and all your glucose reserves are depleted? In these cases, the body starts to use fat, breaking it down to ketone bodies (hence the name of the diet) – short fragments of fat molecules that include beta-hydroxybutyrate, acetoacetic acid and acetone. As you can see, two of the three ketone bodies are acids – remember this as you read on.

Ketone bodies are distributed throughout the body and absorbed by cells (except liver cells, as they cannot get energy from ketone bodies) and give even more energy per unit mass when compared to glucose.

Where is the problem?

First of all, ketone bodies are acids. And increasing their concentration in the blood changes the acid-alkaline balance. Healthy adults are unlikely to see their blood pH change to critical levels but children or, for example, people with diabetes are very likely to experience acidosis – the acidification of the blood caused by elevated levels of ketone bodies.

Secondly, the process of obtaining energy from ketone bodies is chemically completely different from that of glucose and, under normal conditions, this process is very rarely activated, the necessary enzymes being scarce.

To give you an idea of how significant changes occur in the body during ketosis, here are two blood samples:
A – a blood plasma sample from a person in ketosis;
B – blood plasma sample from a person with normal carbohydrate intake.

Ketogenic diet and obesity

On the one hand, everything looks very optimistic – several publications and research results confirm the effectiveness of the ketogenic diet for obesity – fat mass is lost while muscle mass is maintained, which is difficult to achieve with conventional diets.

On the other hand, it is clearly stated that the Keto diet is an obesity treatment and should be used like any other medicine, with monitoring of the condition and only under constant medical supervision.

It is imperative to monitor kidney health regularly. A precise and gradual transition to the keto diet and a return to a traditional diet is essential. The duration of the keto diet can vary from two weeks to a year (usually a strict carbohydrate restriction of -5% of daily calorie intake – is set for a limited time, followed by “relaxation” periods of several months).

Ketogenic diet and diseases

The keto diet first appeared in 1920 and gained popularity as an effective treatment for epilepsy. It is still used as a complementary treatment for epilepsy in cases difficult to treat with drug therapy, although how this method works at the molecular level has not yet been fully explored.

For patients with type 2 diabetes (non-insulin-dependent), this diet has proven to be an effective and fairly safe method to lose weight and control blood glucose levels.

Read about the use of the keto diet for the treatment of various diseases here.

How to achieve ketosis?

To start using ketone bodies as an energy source, you need to significantly reduce your carbohydrate stores so the fastest way to achieve ketosis is fasting.

However.

When fasting, you don’t get enough of important nutrients.

Therefore.

The best way to achieve ketosis is to follow a low-carbohydrate diet limiting carbohydrate intake to no more than 50 grams per day (the maximum amount of carbohydrate to induce ketosis varies from person to person).

Side effects of the keto diet

The ketogenic diet is not the most physiological diet because it significantly alters your metabolism, forcing it to work in a “reserve” mode that is rarely used when eating a regular diet. This is why various unpleasant sensations, especially when switching to the diet (putting yourself into ketosis) and vice versa, are quite common. Headaches, nausea, vomiting, abdominal distress and back pain are the most common.

Disturbances in mineral and fat metabolism, kidney stone formation, and metabolic acidosis (a change in blood pH towards the acidic side) are also common. In children and people with impaired insulin sensitivity, acidosis can reach critical levels, leading to coma.

Side effects occurring during entering into ketosis

“Keto flu” Common symptoms include fatigue, headache, dizziness, nausea and irritability, which usually appear within the first few days of starting a ketogenic diet.
Reduced insulin levels can lead to increased excretion of electrolytes such as sodium, potassium and magnesium, which in turn can cause electrolyte imbalances and symptoms such as muscle cramps, weakness and palpitations.
Changes in fibre intake and gut microbiota can cause constipation, diarrhoea and other symptoms associated with gastrointestinal disorders.

Side effects of being in ketosis

“Keto breath”. The formation of ketones, particularly acetone, can cause bad breath, often described as a metallic nail varnish-like smell. This odour is a common side effect when you are in ketosis.
Increased urination. Ketosis can have a diuretic effect, which can cause dehydration (and increase the risk of kidney stones) and loss of electrolytes. Increased excretion of electrolytes such as sodium, potassium and magnesium, which can cause symptoms such as muscle cramps, weakness and palpitations.
Constipation and/or diarrhoea. Changes in fibre intake and the composition of the intestinal microbiota may continue to cause gastrointestinal discomfort, leading to constipation, diarrhoea or irregular bowel movements.
Lower physical performance. In some people, ketosis may lead to reduced physical performance and/or endurance during intense exercise. This happens because the body adapts to use fat as its main source of fuel rather than glycogen.
Insomnia or sleep disturbances. Ketosis can cause hormonal changes or changes in neurotransmitter activity, which in turn can affect sleep patterns – making it difficult to fall asleep or stay asleep.
Temporary hair loss. Some people may temporarily lose their hair during ketosis. This could be due to changes in nutrient intake or hormone fluctuations, but hair usually grows back as the body adjusts to ketosis.
Menstrual cycle disturbances. This may include irregular periods, changes in menstrual flow or amenorrhoea (absence of menstruation). Hormonal changes and changes in energy balance can exacerbate these effects.

Side effects of coming out of ketosis

Fluctuations in energy levels or mood, when the body starts using carbohydrates as the main source of energy again.
As the body starts to use carbohydrates again, water retention may occur, causing temporary weight gain or bloating.
Rapid changes in carbohydrate intake can also affect blood sugar levels, leading to symptoms such as cravings, fatigue or irritability.

Keto diet foods

	Recommended foods	Must be excluded from the menu	Can be eaten sometimes
Meat	– Chicken. – Turkey. – Beef. – Pork. – Organ meats (liver, etc.) – Venison.	– Breaded meats – Industrially processed meats.	– Bacon. – Low-fat meats such as skinless chicken breast.
Dairy products	– Butter. – Cream. – Whole milk cheeses including cheddar, goat’s cheese and mozzarella. – Whole milk yoghurt.	– Ice cream. – Milk. – Skimmed yoghurt. – Sweetened yoghurt.
Fish	– Herring. -Mackerel. – Salmon. – Trout. – Tuna.
Eggs	Preferably eggs from organically raised hens.
Nuts and seeds	– Pecan nuts. – Almonds. – Chia seeds. – Linseeds. – Peanuts. – Pumpkin seeds. – Walnuts. – Unsweetened nut butters.	– Chocolate-covered nuts. – Cashews. – Sweetened nut butters.
Oils and fats	– Avocado. – Coconut products. – Fruit and nut oils such as avocado, coconut, olive and sesame oils. – Olives.	– Margarine. – Vegetable oils, including rapeseed and corn oil.
Vegetables	– Asparagus. – Broccoli. – Cauliflower. – Onions. – Celery. – Aubergine. – Leafy greens. – Mushrooms. – Tomatoes. – Peppers. – Other non-starchy vegetables.	– Butternut squash. – Corn. – Potatoes. – Sweet potatoes – Other starchy vegetables.
Fruit and berries		– Ananas. – Citrus fruits. – Dried fruits. – Grapes. – Pineapples.	– Berries.
Beans and legumes		– All legumes. – Chickpeas. – Lentils.
Spices and dips	– Herbs and spices. – Lemon juice. – Mayonnaise without added sugar. – Salt and pepper. – Vinegar. – Salad dressings without added sugar.	– Barbecue sauce. – Ketchup. – Maple syrup. – Salad dressings with added sugar. – Sweet sauces.
Cereals and flour products		– Baked goods. – Bread. – Breakfast cereals. – Crackers. – Pasta. – Oats. – Rice. – Wheat.
Beverages	– Water. -Sugar-free almond or flax milk. – Bone broth. – Unsweetened tea and coffee.	– Beer. – Fruit juices. -Lemonades. – Sports drinks. – Sweet alcoholic beverages. – Sweetened tea and coffee.	– Alcoholic beverages low in carbohydrates, such as vodka.
Other		– Artificial sweeteners. – Candy. – Coconut sugar. – Fast food. – Industrially processed foods. – Sugar.

How to tell whether you are in ketosis?

This can be detected by a blood or urine test – if your blood ketone levels are 0.5 millimoles per litre or more, you are in ketosis.

A blood ketone test will give you real-time results, while a urine test will tell you what your ketone levels were a few hours ago.

There is also a set of signs that can tell you are in ketosis with relative certainty:

Bad breath (acetone smell).
Feeling tired (usually temporary).
Dry mouth.
Increased thirst.
Decreased urination.
Diarrhoea or constipation.
Decreased appetite.
Decreased hunger.
Headache and nausea.
Insomnia.

Key takeaways

The keto diet can indeed help you lose body fat without losing muscle and is more effective than simple calorie counting.

But.

It is also very dangerous for your health, so you should definitely not do it for yourself. As I said, if you want to take the risk, you should do it under medical supervision and with your health being monitored at all times.

So.

Think about whether you actually need a ketogenic diet.

During a keto diet, the body makes many biological adaptations (lower insulin levels, increased fat breakdown, etc.).

Therefore.

Before you change your diet, you need to make sure that your fat metabolism is OK. The keto diet should not be followed if you are breastfeeding, during pregnancy or if you have health conditions such as pancreatitis, liver failure or fat metabolism disorders.

Entry and exit from the diet should be gradual, with careful monitoring of well-being and regular monitoring of blood glucose and ketone levels, possibly up to three times a day. It is important to drink plenty of water, eat vegetables and take vitamins and minerals while dieting.

Remember that “paper can bear anything “ – if you are offered a keto diet or ketogenic products, the name is likely their only connection to the keto diet.

But.

If you want to play with your health, first try cutting out fast carbohydrates (fruit, juices, sugary fizzy drinks, sweets, biscuits, cakes, buns … and all other sugar-containing foods) as an experiment. You will probably lose weight and learn what it is like – to live with limited carbohydrate intake.

Exercise, eat tasty and – be healthy!

Sources

Ketogenic Diet

History of the ketogenic diet

Biochemistry, Ketogenesis

Ketone Bodies

Physiology, Glucose

Consumer Reports of “Keto Flu” Associated With the Ketogenic Diet

Ketogenic diets: Boon or bane?

Halitosis: From diagnosis to management

Ketogenic Diet – Uses, Side Effects, and More

Breath acetone as a potential marker in clinical practice