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The Energy Reboot Blog

by Moira Newiss


How Eating Keto Can Fix Your Fatigue

This blog will make you think differently about fat and how it serves an important role in making energy and how it can increase the amount of energy you produce and maybe even supercharge it! You will learn that ketones are made from fat and how to try a ketogenic diet to help fix your fatigue.

How Eating Keto Can Fix Your Fatigue

Is Fat Bad For You?

Do you think of fat as being bad for you? Do you think eating fat will make you fat? Do you believe fat is bad for your heart? Did you grow up believing low fat was best? Would you be surprised to know that much of what you probably believe about fat is wrong? Most importantly eating good quality fat is not only goo for you, it can help you fix your fatigue!

The problem is that we grew up in a world where we were taught by our parents, by our teachers and by the government that fat was bad for us. We were told that fat was the biggest problem for our health and we should eat a low fat diet. As a result fats were take out of lots of food, take yoghurt for example, and replaced with sugar. So not only did we reduce fat but we also increased our sugar intake.

Well unfortunately this message turned out to be wrong and has had devastating effects on our health as a society. The original research that changed the public health messaging took place in the middle of the last century. A researcher by the name of Ancel Keys published work showing that he fat increase in diets correlated with a rise in heart disease. But later it was discovered (although not originally published) that his data also showed that sugar increased at the same rate. So fat was given the blame when it might have been sugar all along. As a result governments changed their public health and dietary advice and made us fear fat. Another scientist called John Yudkin published research showing that sugar was the problem but this was ignored. Since then we have had an epidemic of obesity and diabetes and our general health has declined.

Unfortunately despite the relatively recent changes in dietary advice in the US and UK we still have schools teaching subjects such as home economics suggesting that butter should be swapped out for margarine and the supermarkets are still full of low fat products. If I take yoghurt as an example if you buy anything other than natural yoghurt you are likely buying yourself a sugary treat. Some yoghurts have as much as 23g of sugar in a pot of 126g which is equivalent to 4 ½ teaspoons of sugar. Once the fat was taken out sugar was needed to make the yoghurt more palatable as low-fat unsweetened products are not tasty!

But getting back to high fat diets, our ancestors who were hunter and gatherers would have survived much of the year using fat as their main source of energy, especially in temperate climates like here in the UK. There would only have been a short period of a couple months each year when berries and fruits such as apples, pears and plums would have been available to eat and maybe another couple of months when they would have dug up root tubers (vegetables) to eat.

Evolutionary anthropologists agree that our ancestors would have survived most of the winter, spring and summer months on a high fat animal diet with a boost during the late summer and autumn of sugary and starchy fruits and tuber. This means that we are genetically adapted to eat like this and that doing so is likely to be good for us.


What About Carbohydrates?

You might have heard of people eating low carb to help their health and many doctors now believe that much of the current epidemic of chronic disease has carbohydrate intolerance and insulin resistance at the root cause. When you eat any kind of carbohydrate it will break down into simple sugars and are absorbed into your blood stream. Being carbohydrate intolerant means that we are not able to effectively deal with the amount of carbohydrates that are in our diet and as a result our blood sugar becomes difficult to manage. As a result we produce more and more insulin (a hormone produced in the pancreas) to help move the sugar out of our blood and into our cells.

Eventually our cells become more resistant to the message (insulin resistance) and our blood sugar can rise too high, something that we see when people become diabetic. As a population our carbohydrate consumption is leading us towards a situation where many people may have some amount of insulin resistance, not necessarily diabetic levels, but also not helpful for our health.

Insulin is also our fat storage hormone and any sugar that is not immediately used for energy is stored as fat in your cells. This is the main mechanism in the body that results in fat being deposited. If you thought that you got fat from eating fat you now know that instead carbohydrates as the main culprit.

High Fat & Low Carb

Eating low carb means cutting back on the amount of carbohydrate in your diet, this includes sugary and starchy foods such as cakes, biscuits, sweets, cereals, bread, pasta and to some extent starchy root vegetables such as potatoes. Low carb is generally considered to be between 50g and 150g of carbohydrates a day. Generally when you do this you increase your fat intake to make up the difference. But this is not a low enough amount of carbohydrate for most people to make it a keto diet.

On a keto diet you need to be eating enough fat to be burning it as your main source of energy for your body. To do this you generally need to be eating less than 50g of carbohydrates a day and many people need to go as low as 20g a day, at least to begin with until your body adapts to burning fat. You are aiming to move your body into something called ketosis, this is when the amount of fat in your diet enables your body to use a different mechanism for producing energy, it uses the fat to create ketone bodies which are molecules that the body can feed into your energy making process. This is a very clean way of making energy, very few high energy free radical molecules are produced compared to burning carbohydrates and this means it is much more anti-inflammatory.

Food Pyramid

You can see that a keto diet reverses the food pyramid that we typically think we should be eating in terms of macronutrients, fat, protein and carbohydrate. You will notice that protein intake generally remains stable.

Ketones & Ketosis

Ketones are produced in the liver, a process known as ketogenesis and when this is happening you are said to be in ketosis. There are three major ketone bodies that are made and used by the body for energy: acetone, acetoacetate, and β-hydroxybutyrate. Inside your cells you have tiny little organelles called mitochondria which use food and oxygen to create ATP (adenosine triphosphate) the fuel that your body runs on. The mitochondria can use carbohydrates and fats to make ATP but they work even more efficiently using ketone bodies and this is especially true for your brain cells which have a preference for ketones.

When you adapt your diet so it is keto friendly you may notice several things happening with your body that give you a clue you are ketosis:

  1. Clean shiny teeth. Firstly, your teeth feel clean and shiny as the lack of carbohydrate reduces the build-up of tartar on them.

  2. Your brain feels like it is working better as the brain prefers to burn ketone bodies instead of glucose (there is interesting evidence becoming available about how ketones can help improve the brains performance for conditions such as Alzheimer’s, migraine and depression).

  3. Your mind feels calmer and happier as when you are in ketosis you produce more GABA which is a calming neurotransmitter, you also generate more serotonin which helps stabilise your mood and more dopamine which can help increase your feeling of well-being.

  4. Quick weight loss due to water loss. Your liver and muscle store carbohydrates as glycogen which helps retain water. The glycogen gets used up when you move to fat burning and therefore you lose the extra water too.

  5. Your blood sugar levels become more stable. Less carbohydrates means less of a rollercoaster of blood sugar highs and lows which reduces cravings. Mid-afternoon energy lows and often improves sleep too.

  6. You feel fuller for longer – this is partly because betahydroxybutryate is a signalling molecules involved with appetite suppression.

  7. Digestive problems improve. Reducing carbohydrates helps avoid microbes fermenting them in the upper gut which often leads to bloating. A keto diet helps keep the upper gut ore acidic and free of unhelpful microbes.

  8. Joint pain and other aches and pain often improve too due to the anti-inflammatory nature of the keto diet.

Health Benefits of a Keto Diet

So far you might think this all sounds good but there is much more research showing how a ketogenic diet can be a health benefit. It can help to reduce and, in some cases, even reverse the outcome of chronic diseases e.g. Type2 diabetes. Where GPs are using a ketogenic approach to treating Type2 Diabetes they are getting up to a 50% remission rate – there is no drug that can do this! Then there is research that shows that a keto diet can hep with cancer outcomes, weight loss, cardiovascular disease, high blood pressure, gut health and mental health conditions. Interestingly research shows that a ketogenic diet can even affect your epigenome, that means that it can signal to your cells to switch on or off different genes which may be one of the reasons behind all these amazing health benefits!

Benefits of a Ketogenic Diet

Ketones Supercharge Your Mitochondria

You might have spotted that I haven’t yet mentioned chronic fatigue. There is a good reason for that in that there is not much research that has been done on chronic fatigue syndrome itself with a ketogenic diet. But if you dig deep you can find some very interesting papers and pieces of evidence. Dr Sarah Myhill who is a doctor who specialises in chronic fatigue syndrome and did a very interesting study. She took a group of people with chronic fatigue syndrome and assessed their mitochondrial function. At the start of the study she found that mitochondrial function was impaired i.e. the mitochondria were not effectively producing energy. All of the participants were put on a basic treatment regime that consisted of 1) eating the evolutionary correct stone-age diet (this was a keto diet), 2) ensuring optimum hours of good quality sleep, 3) taking a standard package of nutritional supplements, and 4) getting the right balance between work and rest. She found that all of the patients who followed the treatment regime improved their mitochondrial function by on average a factor of 4 (which is a lot!).

Why might ketone bodies help with chronic fatigue? Researchers found the answer to this question when they first discovered ketone bodies and tested how the heart responded to different kinds of fuel including glucose and ketones. They uncovered how ketone bodies were incredibly potent as a fuel supply and the reason is because they are a thermodynamically superior fuel. This means that they have a higher amount of potential energy held in the chemical bonds in the molecules. Ketones therefore have more energy to begin with than glucose does and when energy stored in ketone bodies is captured by the mitochondria it releases more ATP (remember the energy you make). If you have read my previous posts (see here) about how energy is made in the body you will know that the last part of the process is the electron transport chain and that electrons are removed from the energy molecules NADH and FADH2 and transferred into the space between the mitochondrial membranes. This creates a charged gradient with more positively charged electrons inside the membranes. The final step of the energy production process is when these electrons flow back through the ATP pump. It is basically like a tap that is physically turned as the electrons flow through it and into the mitochondrial matrix (the inner part) and as they flow they generate ATP.

With ketone bodies there is more NADH produced so there are more electrons and the electrons are also transferred with a greater force, like the water building up behind a dam. The gradient becomes more highly charged so that when the tap is running it is more like a waterfall and this superchargers the cell with ATP. In fact the early researches who discovered this found that ketones always resulted in a metabolic efficiency of 25% compared to the usual 10% when it is fuelled by carbohydrates. Totally fascinating I’m sure you will agree! If you haven’t quite understood it please go back and look at my previous posts as it is really worth getting your mind around.

Ketones - Your 4th Fuel

Fantastic Fats

If you want to have a go at a ketogenic diet you basically need to increase the amount of healthy fats in your diet and reduce the carbohydrates. So I am going to take a look at the healthy fats and where you can get them from, there are three main types, monounsaturated fats, polyunsaturated fats and saturated fats. You also want to avoid transfats and hydrogenated fats which I will touch on too.

Fatty acids are the building blocks of all fats, these fatty acids consist of chains of carbon (C) atoms, with hydrogens (H) attached. They are put into classes of fats based on the length of the carbon chain of atoms they contain: short chain, medium chain, long chain and very long chain. In addition to the length of their carbon chain, fatty acids can also be saturated or unsaturated hence the terms saturated, monounsaturated or polyunsaturated. Although many fats found in nature are actually a combination of several types of fatty acids. For example, coconut oil contains both saturated and unsaturated fat and olive oil contains both monounsaturated and polyunsaturated fat.

Saturated fats come mainly from animal sources and are solid at room temperature. Their chemical structure does not contain any double bonds, therefore they are therefore said to be saturated with hydrogen atoms. Unsaturated fats, are mainly found in plant sources and are liquid at room temperature. They can contain one double bond (monounsaturated) or more than one double bond (polyunsaturated). This means that the carbon atoms are joined to each other in the chain with two bonds rather a single bond which also has hydrogen atoms attached to it. The more double bonds a fat has, the more fragile it is meaning it can be oxidised and become rancid more easily. In the past saturated fats got a bad press and were blamed for blocking arteries and causing heart attacks. Studies done reducing saturated fat in the diet did not correlate with any cause of death, stroke, heart attacks, or development of Type 2 diabetes. If you want to know more about this I would suggest reading “The Pioppi Diet” by Dr Asseem Halhotra (NHS Cardiologist) and “The Clot Thickens” by Dr Malcom Kendrick (GP).

Looking at coconut oil again we find it is 92% saturated, 7% monounsaturated and 1% polyunsaturated. This means that it is mainly a saturated fat is therefore solid at room temperature. Olive oil is 14% saturated fat, 78% monounsaturated fat and 8% polyunsaturated fat and is liquid at room temperature.

You are probably wondering about omega-3 oil as it’s the one everyone knows is good for us! Well there are three types of fats within the polyunsaturated group of fats: omega 3, omega 6 and omega 9. The numbers 3, 6 and 9 refer to the number of carbon molecules before the first double bond in the chemical structure. These types of oil need to be consumed in balance with each other. Ideally we should be eating a lot more omega-3 fat than omega-6 (which has a more inflammatory effect). If we go back to our hunter gather ancestors they would have done this quite naturally from nutritious sources of omega-3 like oily fish and eggs as well as eating fatty cuts of meat that came from grass fed animals. The problem today is that animals that are intensively reared for their meat and eggs are fed an unnatural diet high in grain which is omega-6 rich. This means the meat and eggs have a much higher omega-6 content than is normal. Plus we are consuming many more highly processed foods today that have a high omega-6 content such as refined vegetable oils (like sunflower oil) and processed foods (like biscuits, crisps, chips and cakes).

As a result the ration of omega 6:omega 3 fats we consume can be as high as 20:1, but the optimal range should be much closer to 1:1. Omega-6 has a helpful role in supporting the inflammation response in the body when it is needed (like when we are ill or injured) but in the levels that are currently in our diets it is associated with chronic inflammation and linked to health problems like heart disease and diabetes. To avoid this problem you need to keep your consumption of omega-6 fats down and increase your omega-3 fat intake.

For now all you really need to remember if that fat is essential for us to survive and thrive, it is crucial as we have seen for making optimal energy but it has other really important roles in things like vitamin absorption and storage and hormone production. In fact 60% of your brain is fat and fats are essential for the normal functioning of your nervous system. Every cell membrane in your body consists of a double layer of fatty acids and dietary sources of healthy fats help keep the membrane flexible and fluid so that your cells function well. I think you might be getting the message about how important fats are for you and choosing high quality healthy fats is the key.

Before we move onto look at where we can find these fats in food I want to mention transfats and hydrogenated fats. I am talking here about artificial trans fats which are also called partially hydrogenated fats, these are found in foods that have undergone lots of processing to make them more stable so that they can have a much longer shelf life put on them. These fats are thought to be hazardous to human health and you want to avoid them. They are found in lots of processed foods such as cakes, biscuits, deep fried foods and in vegetable oils (like sunflower oils, rapeseed oil) and margarine. They are best completely avoided.

Healthy Fats

Where to Find Healthy Fats

Lets take a look at some examples of the best food sources for the different types of fats.

  • Saturated fats are found in pork, beef, lard, butter, cheese, cream, coconut oil and palm oil as well as in smaller amount in

  • Monounsaturated Fats are found in foods including olives, peanuts, avocados, almonds, hazelnuts, macadamia nuts, pecans, pumpkin and sesame seeds.

  • Polyunsaturated Omega-3 Fats are found in walnuts, flaxseed, sunflower seeds, oily fish (including salmon, tuna, trout, mackerel, sardines), olives and grass fed animal meat.

  • Polyunsaturated Omega-6 Fats are found in sunflower seeds, walnuts and meat.

  • Polyunsaturated Omega-9 Fats are found in olive oil, macadamia nut oil and avocados.

What Does a Healthy Keto Diet Look Like?

Keto diets have come in for a bad rap from some people as being lacking in micronutrients and causing gut problems. There is research that shows this is only a problem when a keto diet is done badly without following appropriate nutrition advice. Done properly and it can help optimise these things!

So a well-formed keto diet that can get you into nutritional ketosis should include the following:


A low level of carbohydrates (less than 50g a day and often as low as 20g a day) that come from seasonal fruits and vegetables that grow above the ground and are low in starches and sugars. This includes:

  • Plenty of leafy green vegetables such as spinach, spring greens, rocket, lettuce, pak choi

  • Plenty of cruciferous vegetables things like cabbage, brussel sprouts, broccoli and cauliflower

  • Sulphur rich vegetables like leeks, onions and garlic

  • Salad vegetables/fruit such as spring onions, cucumbers, tomatoes and peppers.

  • Herbs and spices

  • Low sugar fruits including blueberries, raspberries, strawberries, apple, pears, plums


  • A mixture of all types of healthy fats with an emphasis on omega-3 fats.

  • Saturated fat from eggs, avocados, coconut, meat, dairy

  • Monounsaturated fat from avocados, nuts and seeds

  • Polyunsaturated fat from walnuts, flax seed, chia seed, oily fish, grass fed meat and olive oil.


Each meal or snack should contain protein. A good indication at each main meal (if 3 a day) is a portion of protein roughly the size of your palm. You will need to each a bit more if your main sources of protein are plant based as generally the digestibility and absorption of protein from plant sources is poorer than from animal sources. Food sources of protein include:

  • Beef, lamb, pork, venison, chicken, turkey

  • Dairy sources including cheese, yoghurt and kefir

  • Legumes like peas, beans and chickpeas

Food Types

How Do I Know I am in Ketosis?

When you try a keto diet the entire point is to get into ketosis so you may want to test to make sure that you have achieved what you set out to do! There are a few things other than just nutrition that affects ketosis such as your specific response to individual foods, the timing of your eating (or fasting), the activities you do (such as exercise) and even your stress levels. The signs and symptoms that I listed above that can be a good indication but most people like to test. You can do this three different ways using breath, blood or urine. Testing is helpful as monitoring your ketone levels help you to understand how your body is responding and gives you clues about how you might want to adjust things if you are struggling to get into ketosis.

Testing is based on the three types of ketone bodies that are produced, you might remember these are: acetoacetate (AcAc), Acetate (Acetone) and Beta-hydroxybutyrate (BHB).

Acetoacetate is the first ketone body that is produced and is measured in your urine but is a less reliable indicator once you become keto adapted over a few weeks. Acetone is the least abundant ketone body and is exhaled through the lungs as a waste product, it is actually not used for energy production at all but gives a good indication of overall keto levels which is done through breath testing. BHB is the most abundant ketone produced and is transport in the blood for use as an energy fuel and is therefore measured by testing your blood.

Urine test sticks can be purchased and are a good low cost option for beginners. Make sure you stay well hydrated and check the test sticks are well sealed and within use by date as they are sensitive to humidity in the air. Keep the pot well sealed and away from moisture.

Breath testing can be done using a breath monitor, there are various brands such as Ketonix and Ketomojo. Be aware that several compounds can affect the sensitivity of the reading including, mints, chewing gum, some sugar substitutes, tobacco and e-cigarettes, cough drops, mouthwash, foods like garlic, drinks like alcohol, coffee, green tea and fermented drinks and even some drugs. Also results can vary depending on your rate and depth of breathing and as a result how your acetone levels are reflected in your breath. It is important to follow the manufacturers advice and to repeat the sample a few times to make sure you get an accurate reading.

Ketonix Tests

Blood testing is the gold standard as it is measuring the most active form of ketones in your body, beta-hydroxybutyrate and therefore it is the most important one to measure. It gives the most accurate assessment of whether you are in ketosis and how your body is performing on a keto diet. You can buy ketone blood testing monitors that use a finger prick process where you put a drop of blood onto a test stick. Often monitors will measure blood glucose as well which can be another useful feature.

Side Effects & Keto Flu

Some people can transition to a keto diet without any problems, other people find they feel slightly worse in the short term. Short term side effect can include fatigue, brain fog, dizziness, irritability, muscle cramps or digestive problems and is collectively known as the “keto flu”. But don’t despair it is usually short lived and there are things you can do to help yourself through it.

The reason it happens is that you are changing your body’s metabolism from burning carbohydrates to burning fat as your main fuel. It can feel like withdrawal symptoms – which perhaps it is since sugar is a highly addictive substance and you are effectively weaning yourself off it (remember all carbohydrates break down into sugar!). It is very rare that this lasts longer than a week and for most people it is just a couple of days. If you were already eating a fairly low carb diet than you are likely to transition without any problems at all.

There are few things that you can do to help your body cope with the transition:

  • Drink plenty of water. As I mentioned above you lose water from your body on a keto diet so dehydration is a common problem. So keep drinking throughout the day.

  • Supplement with electrolytes. As you lose water you also loose electrolytes (salts) The most common cause of keto flu is a lack of electrolyte salts including sodium, magnesium, and potassium. You can increase dietary sources of these salts, for example by adding salt to your food, eating food sources of magnesium such as spinach, pumpkin seeds and chia seed or you can add an electrolyte liquid drops to your water.

  • Eat more fat. Sometimes if you have dropped your carbohydrates but not increased your fats enough you are just not getting enough energy to fuel your body and brain effectively. Perhaps add a healthy keto friendly snack in such as peanut butter with apple slices or the creamed coconut berry pot (see recipe below).

  • Cut back on exercise for a short while. If you are someone that does strenuous exercise you might find it more difficult for your body to adapt. Maybe cut back for a couple of weeks and opt for walking, yoga and less strenuous cycling as options.

  • Rest up a little. Try to get plenty of sleep nightly and rest up when you feel tired. Remember your body is adapting so give it a little help along the way!

Above all if you have got this far – give yourself a pat on the back, do something that brings you joy and remember you are one of only a few people who will have tried to do this. As your body adapts you will feel healthier and more energetic, your brain fog will clear and you will thank yourself for persevering a little longer!

To help you try a Keto style of eating and give you plenty of recipe ideas I have written you a Quick Start KETO guide.

How Eating Keto Can Fix Your Fatigue

If you would like a copy of my Quick Start KETO Guide then you can download it by clicking here. It provides you will all the information you need to get started including 16 keto recipes, a meal planner and a condensed version of all the tips to get you into ketosis and avoid any problems.

Medical Disclaimer: This blog is for information purposes only and does not constitute medical advice. It is especially important that you seek medical advice before starting a keto diet if you are on any medication including those for diabetes, heart disease, blood pressure and mental health conditions.


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