Ketogenic diet: the definitive (science-backed) guide to keto for beginners

Ketogenic diet helps weight loss

Not another article on the ketogenic diet!

Yes, but this one’s different…

There’s so much hype and exaggeration around keto that it’s time someone cut through the nonsense.

Now, I may be getting ahead of myself, but unless you’ve been living on a different planet for the last few years you will have heard of the ketogenic diet.

It’s the latest fad. It’s everywhere.

And as often happens with fads there’s controversy.

Some people are almost evangelical in their promotion of keto whilst others think it’s a dangerous gimmick causing long-term health problems.

The zealots argue that it has huge metabolic advantages over other diets; that it programs our body to use fats as the primary fuel source much more than other diets.

They’ll also tell you that it will improve your mood, give you more energy, improve your mental sharpness and your ability to deal with stress.

On the flipside, the opponents believe that it’s impossible to stick to, causes nutrient deficiencies and that there are more effective diets.

As with most things, there are three sides to the story. The proponent’s side, the detractor’s side and the truth… which is somewhere in between!

In this post, I’ll reveal the truth.

And I’ll do it using scientific proof rather than a desire to sell you something 😉.

What is a ketogenic diet?

The popularity of the ketogenic diet is mainly due to the fact that over 20 studies1 have shown that it can help you lose weight and improve your health.

There is evidence, for example, that it can help fight diabetes2, cancer3, epilepsy4 and Alzheimer’s disease5.

So, what exactly is it?

It’s simply an extremely low carb, high fat diet that’s similar to the Atkins plan.

On the ketogenic diet you drastically reduce the amount of carbs you eat and replace them with more fat and protein.

It’s called “ketogenic“ because the aim is to put your body into a state called “ketosis”. In effect, your mimicking the effect of fasting to minimise the release of a hormone called insulin in your body.

When you don’t eat many carbs your body will start to use things called “keytones“ which are extremely efficient fuel for our muscles and brain6.

Once your body starts to use keytones as fuel you’re said to be in “ketosis”.

(I don’t want to get bogged down in scientific terminology but it’s useful to understand these things as you’ll see them everywhere.)

This “keto adaptation” takes a few weeks. Prior to reaching that state many people have a drop in energy, mood swings, and problems concentrating. But, once you’re there these side effects should decrease.

Enough of the complicated scientific terms. What does this mean in the real world?!

When you reach keytosis your body becomes very efficient at burning fat for energy. It is from fats that ketones are produced.

This, of course, helps cause weight loss but that’s not the only way keto helps shift the pounds.

We’ll look at these in more detail in detail below.

The different types of ketogenic diet

There are a few different types of ketogenic diet but they all share one thing in common: a massive reduction in the amount of carbs you can eat.

You’ll eat a diet that is made up predominantly of fat (around 70 to 80%) with around 15 to 20% coming from protein and the remaining 5 to 10% from carbs.

Standard ketogenic diet (SKD)

Macronutrient profile: 75% fat, 15 to 20% protein, 5 to 10% carbs

This is the very low carbohydrate, high-fat, medium protein diet most people doing keto try.

On the Standard Ketogenic Diet you’ll be eating around 150g of fat every day. Depending on your eating habits at the moment this is likely to be a BIG increase.

In combination with this, your carb intake will drop to around 50g per day. For many, this will mean eating only 1/6 of the carbs we’d been eating before.

50g per day isn’t much at all. To limit carbs to this level means sticking to things like leafy greens, non-starchy vegetables and low-carb fruits such as berries and melon.

Cyclical ketogenic diet (CKD)

Macronutrient profile: 75% fat, 15 to 20% protein, 5 to 10% carbs on keto days and 25% fat, 25% protein and 50% carbs on “re-feed” days

In this version of the keto diet you alternate or “cycle” days on the Standard Ketogenic Diet with a few higher carb days. 5 on, 2 off is a typical plan.

With the Cyclical Ketogenic Diet you can eat wholefood carbs such as fruits, starchy vegetables, dairy products and wholegrains on your off days.

But, it’s not an excuse to indulge in pizza, fries and doughnuts!

Targeted Ketogenic Diet (TKD)

Macronutrient profile: 70% fat, 15 to 20% protein, 10 to 15% carbs

This version of the ketogenic diet is aimed at athletes and other active individuals who could benefit from a higher carb intake.

On the Targeted Ketogenic Diet you’re allowed an extra 20–30g of carbs (wow!)

That’s not a lot and should be consumed before and after workouts or other high energy activities.

The rationale for the additional carbs is to allow for higher intensity exercise and improved recovery.

Again, the idea is to get the additional carbs from whole foods such as fruit, dairy or wholegrain products.

High Protein Ketogenic diet (HPKD)

Macronutrient profile: 60 to 65% fat, 30% protein, 5 to 10% carbs

This variation of keto allows for much more protein.

By eating around 120 to 130g of protein per day you’ll experience less hunger and as a result many find this modified keto diet easier to stick to.

The big downside, though, is that your body probably won’t reach the state of ketosis which is the whole point of the ketogenic diet in the first place!

And if you’re not in keytosis you won’t get the benefits…

The reason for this is that in certain situations protein, like carbs, can also be converted into glucose. With glucose present our body’s aren’t tricked into producing ketones.


Ketogenic diets melt the fat

The advocates of the ketogenic diet will tell you that it’s highly effective way to lose weight and decrease your risk of developing various diseases.

Let’s start by having a look at the evidence around weight loss.

Firstly, ketogenic diets are much more effective than low fat diets for losing weight.

For example, one study7 found that people who followed a ketogenic diet lost 2.2 times more weight than people following a low fat diet.

They’re also more effective than typical healthy eating plans.

Another study8 showed that participants eating a keto diet lost three times more weight than people following a “healthy eating” diet (6.9kg (15.2lbs) compared to 2.1kg (4.6lbs)).

And they beat low calorie diets too.

A study9 comparing a ketogenic diet to a low calorie diet found that after 2 months weight loss in the keto group was 13.6kg (30lbs) compared to 4.8kg (10.6lbs). After 12 months, the difference was even more impressive: the keto group lost 19.9kg (44lbs) but the low calorie group had lost only 7kg (15.4lbs)!

That’s a MASSIVE difference.

Why is keto so much better?

There are few reasons.

On a ketogenic diet people typically eat more protein than on other diets. As we saw in our post 14 science packed hacks to lose weight fast (without even trying) eating more protein has a host of weight loss benefits.

For example, protein:

On top of this, the increased use of fat for fuel, reduced blood sugar levels and better insulin sensitivity people experience on keto lead to:

Make no mistake, the ketogenic diet is very effective for weight loss.

Ketogenic diet for diabetes

A ketogenic diet can help in the prevention and management of diabetes. It can also help with something called Syndrome X, a pre-diabetic state that many people have without knowing it.

If you ever feel tired after eating carbs the chances are that you do not tolerate them well.

Diabetes is a condition that causes various changes to the way people process carbs resulting in high blood sugar levels and reduced insulin function.

So, any diet that limits the amount of carbs may be an effective treatment.

One of the big risk factors for diabetes is excess body fat and, as we have seen, the ketogenic diet is effective in helping people lose weight. For this reason alone, it can be a good choice for certain diabetics23.

In fact, one study24 found that by following a keto diet people’s insulin sensitivity improved by 75%.

So what? I hear you say!

“Insulin sensitivity” refers to how well our bodies process carbs.

If you have poor insulin sensitivity, which is the case for most diabetics and people with Syndrome X, then much of what they eat gets stored as fat rather than used as fuel.

On the other hand, if you have good insulin sensitivity more of the food you eat is used as energy and to build lean tissue, rather than being stored as fat.

Another study of people with type 2 diabetes (the type that develops with age) found that by following a ketogenic diet a third of participants were able to stop using diabetes drugs.

If you have diabetes or Syndrome X and are overweight then your doctor will normally recommend losing weight as part of managing the condition.

The ketogenic diet appears to be particularly effective for weight loss in people with these conditions.

One study25 found that people following a ketogenic diet lost 11.1kg (24.4lbs) compared to 6.9 kg (15.2lbs) in a group following a higher carb diet.

This led to 95.2% of the ketogenic group being able to either stop or reduce their diabetes medication whereas only 62% and the other group were able to do so.

Do keto diets decrease heart disease?


One of the major causes of heart disease is inflammation and inflammation is often caused by high blood sugar levels.

As we have seen above, the ketogenic diet can help lower blood sugar levels and improve insulin function. In this way it actively reduces inflammation26.

A meta-analysis27 (a study reviewing a collection of previous studies) looked specifically at the effects of keto diets on heart health.

They found that total cholesterol, triglycerides (a fancy name for fats), LDL cholesterol and blood pressure all decrease on keto diet.

They also found that HDL cholesterol, the good type of cholesterol which has protective effects, increases.

But it seems that the specific foods you eat whilst doing keto also matter.

It has been shown28 for example that people who get most of their protein from animal sources (meats, cheese, etc) had a 43% higher risk of dying early.

Cancer and keto

One of the most exciting things about the ketogenic diet is its potential impact in treating and preventing cancer29.

To understand why keto can be helpful we need to understand a bit of science (but only a bit!)

Nobel prize winner Dr Otto Warburg discovered that 80% of human cancer cells have a much higher need for glucose and, as we know, by following a ketogenic diet we can reduce the amount of glucose in our bodies.

This makes it more difficult for cancer cells to grow. You’re taking away their energy source.

Not only that, a ketogenic diet causes cancer cells to produce less of a substance called “insulin-like growth factor (IGF-1) which acts as a growth signal for cancer. Less IGF-1 = less cancer growth.

There’s more…

Keto also reduces a tumour’s ability to produce another growth signal called VEGF which triggers cancer cells to develop their own blood supply. 

If we cut off the blood supply the cells are starved and cannot grow.

Evidence for the effectiveness of limiting glucose levels in the blood can be found in a study30 from the University of Texas.

In the study researchers limited blood sugar levels in mice with certain types of cancer by feeding them a ketogenic diet.

Amazingly, the cancer stopped developing.

Now, of course, this was a study involving mice and it’s fair to say that the research on the relationship between ketogenic diets and cancer is very early stage.

But it does show some promise, especially in relation to brain cancer31 32.

In fact, one study33 advocated the use of ketogenic diets in combination with conventional radiation and chemotherapy.

Ketogenic diet and Alzheimer’s disease

Alzheimer’s disease is a form of dementia that is estimated to affect over 25 million people around the world.

There is no cure and it’s invariably fatal.

Science isn’t 100% sure of its cause but age34, family history35, inflammation36, insulin resistance37 and being overweight38 are all risk factors.

Now, whilst there is no research which definitively proves a ketogenic diet can prevent Alzheimer’s there is reason to believe it may help39 40.

We know already that keto positively impacts inflammation, insulin resistance and excess bodyweight and as these are all risk factors for Alzheimer’s it seems logical that keto may help prevent the condition developing.

What about people who already have Alzheimer’s?

Again, at the moment there isn’t enough evidence to be sure that ketogenic diets are effective but the authors of one study concluded:

“The ketogenic diet could be an effective treatment and prevention for Alzheimer’s disease, but both keytone production and carbohydrate restriction may be needed to achieve this.”

And an increasing number of doctors are using it successfully as part of managing the condition.

Ketogenic diet and epilepsy

The ketogenic diet has been proven over and over again to effectively treat epilepsy.

Large meta-analyses41 have sown that over half of children following the ketogenic diet have a 50%+ reduction in the number of seizures and a third experience a decrease of 90%+.

Not only that be around 15% experience no seizures at all.

The results are even better where children follow keto for at least 3 months: over half have 90% fewer seizures and 30%+ become completely seizure free42.

It’s not just children that can benefit. Adults experience a significant reduction in seizures as well.

For example, in one study43 50% of adults following a ketogenic diet had a 50%+ reduction in seizures and 33% had an 85%+ reduction.

Not bad!

What makes it even more impressive is that many of these patients had not responded well to standard medical treatments so going keto was a last resort.

How does a ketogenic diet exert these benefits?

It’s our old friend ketones again. They appear to increase levels of chemicals that decrease neuron activity, reduce levels of reactive oxygen and make the brain use energy more efficiently, resulting in fewer seizures44 45.

Other keto benefits

The ketogenic diet has shown promise in treating other conditions too.

For example, there’s evidence that it can improve symptoms in Parkinson’s disease46, help patients with polycystic ovary syndrome (PCOS)47, reduce concussions and boost recover in people with brain injuries48 and improve acne49.

There’s also the possibility that keto may help with anxiety and depression. It has been shown to reduce anxiety and depression in mice. Yes, it’s “only” mice but it is yet another example of the potential benefits keto has50 51.

It will be interesting to see the results of studies in humans.

Finally, a ketogenic diet may also help you sleep better. Studies52 demonstrate that keto improves sleep by increasing slow-wave sleep patterns (the deepest form of sleep) and decreasing REM sleep.

Result: you’ll have fewer wake-ups and feel more refreshed.

Foods you can eat on a ketogenic diet

Ok, so now we’ve been through the benefits of following a ketogenic diet, let’s look at the foods you can eat.

But remember, if you’re going to make keto work you also need to keep your macronutrients (fat, protein and carbs) in certain proportions. (Check out the section on Types of Ketogenic Diet for a reminder).

The following foods are keto-friendly:

Chicken, pork, steak, minced (ground) beef, lamb, bacon, ham, turkey, sausage

Fats and oils
Butter, virgin coconut oil, extra virgin olive oil, ghee, lard, avocado oil, mayonnaise

Certain vegetables
Cauliflower, cabbage, avocado, broccoli, courgette (zucchini), peppers, aubergines (eggplants), tomatoes, asparagus, cucumber, onion, mushroom, spinach, lettuce, green beans, olives

High-fat dairy
Double (heavy) cream, cheese (soft and hard), cream cheese, sour cream

Almonds, peanuts, peanut butter, almond butter, macadamia nuts, pecans, hazelnuts, walnuts

Salmon, snapper, trout, tuna, cod, catfish, halibut, clams, oysters, lobster, crab, scallops, mussels

Blueberries, blackberries, raspberries

Artificial sweeteners
Stevia, sucralose

Hard liquor, dry wine, champagne

Eggs, unsweetened coffee and tea, spices

Keto's banned list

The following are out-of-bounds on a ketogenic diet. Some of the things will surprise you:

Apples, bananas, oranges, grapes, watermelon, peaches, pineapple, cherries, pears, lemons, limes, grapefruits, plums, mango

Wheat, rice, rye, oats, corn, quinoa, barley, millet, bulgur, amaranth, buckwheat, sprouted grains

Root vegetables
Potatoes (sweet and regular), carrots, yams, parsnips, yuca, beets, turnips

Refined products
Cereal, bread, pasta, rice, corn, oatmeal, crackers, pizza, popcorn, granola, bagels, muesli, flour

Black beans, kidney beans, pinto beans, navy beans, soybeans, peas, chickpeas, lentils

Cane sugar, honey, maple syrup, agave nectar, Splenda, aspartame, saccharin, corn syrup

Candy, chocolate, cakes, buns, pastries, tarts, pies, ice cream, cookies, pudding, custard

Certain oils
Canola oil, soybean oil, grapeseed oil, peanut oil, sesame oil, sunflower oil

Beer, cider, sweet wines, sweetened alcoholic drinks

Sweetened drinks
Juice, smoothies, soda, sweetened tea and coffee

Low-fat dairy
Skim milk, skim mozzarella, fat-free yogurt, low cheese and cream cheese

Sweetened sauces and dips

Ketogenic diet meal plans

I’m a nutritionist not a chef so I’m not going to pretend to be the best person to come up with keto recipes.

There are some great recipe sites out there. These are my favourite:

Healthy keto snacks

If you’ve ever been on a weight loss diet then you’ll be familiar with the urge to snack between meals. It’s often the thing that causes diets to fail.

You’re eating fewer calories and your body’s crying out for food. And, of course, it’s not crying out for a healthy snack. It wants something loaded with carbs, unhealthy fats and sugar.

One of the main benefits of keto is appetite suppression and after the first couple of weeks you shouldn’t have the hunger pangs associated with other diets.

That’s the good news.

The bad news is that the ketogenic diet is strict and because of this you’ll need to have keto-friendly snacks in your cupboard or you’ll risk falling out of ketosis.

Here are some quick and easy keto-friendly snacks:

Beef jerky
Check the brand you go for doesn’t contain sugar. If you can find grass fed jerky go for that.

Choose full fat over low-fat versions.

Nuts and seeds
Almonds, pecans and macadamia nuts are all good choices as are seeds like flaxseed (also known as linseed) and chia.

80%+ dark chocolate
Choose a brand with at least 80% cocoa solids that is either unsweetened of sweetened with Stevia.

Cacao nibs
This is the purist form of chocolate. Cacao nibs are not the same as chocolate chips, far from it. Incredibly chocolatey and a delicious treat.

Simply slice in half, remove the stone, sprinkle with salt and drizzle with extra virgin olive oil.

These are one of the best sources of omega 3s and take seconds to cook in the pan.

Pork rinds (crackling)
A crispy alternative to crackers or chips. Check the ingredients list carefully for unhealthy oils. Avoid anything listing “hydrogenated” oil.

Try to find organic and hormone-free versions and buy the ready sliced variety for ease of use.

Keto bars
Not always the best tasting but experiment to your find a brand you like. Make sure they’re free from added sugar, chemicals, gluten, dairy, soya and corn.

Cherry tomatoes
No need to do anything with these, just rinse and eat.

A great piquant snack. Just make sure they’re packed in extra-virgin olive oil.

Vegetable sticks
Simply chop your favourite keto-friendly vegetables into sticks. Great to eat on-the-go.

Hard-boiled eggs
7 minutes in boiling water then plunge into cold water for the perfect boiled egg.

Eating out on a ketogenic diet

Another way people of tend fall off the diet wagon is when eating out.

Here are some tips to help you follow a ketogenic diet when you’re out and about:

Plan ahead

Check out menus in advance.

If there’s nothing that’s keto-friendly then think about which meals can be modified slightly to make them work.

For example, choosing burger and fries but asking the restaurant to remove the bun and replace the fries with a salad.

Add healthy fats

Often you’ll find yourself removing carbs from meals but unless you replace them with fat you’ll end up extremely hungry. This makes falling off the wagon even more likely.

Here are some options:

Beware sauces and condiments

These are the hidden traps for the keto dieter.

The safest plan is to avoid them. By all means ask about their ingredients but you’ll probably find that they’re not keto-friendly.


Another keto trap. Most drinks (soft and alcoholic) are loaded with sugar.

You’re safe with still water, sparkling water, black tea and coffee (or tea/coffee with double (heavy) cream).

Alcoholic drinks in the form of hard liquor, dry wine and champagne are good choices.

Ketogenic diet desserts?

Is there such a thing?!

This is where it gets really tricky.

Most desserts are sweet and full of ingredients that shouldn’t be anywhere near a ketogenic diet.

So, what do you do?
If you must have something then go for the cheese option (without the crackers) or ask for berries with cream.

Alternatively, a rather unsatisfying option is to go straight to tea and coffee.

The 11 most common keto side effects and how to avoid them

There’s no way to sugar-coat it: sticking with the ketogenic diet is hard. We’ve already seen how low compliance rates are.

But if you can stick with it you can expect great results.

It’s not just the regimented food choices that cause people to give up, keto comes with a number of side effects.

Not everyone will suffer side effects but most will experience some in the first few weeks.

Let’s have a look at the 11 most common and the steps we can take to minimise them:

Frequent urination

In the first couple of days of the ketogenic diet your body will be using carbs stored in your muscles for energy.

When it does it releases a lot of water which needs to be processed by your kidneys and expelled as urine.

There isn’t really anything we can do to affect this. It’s a short term condition that will pass in a few days.

Dizziness and drowsiness

As a consequence of getting rid of all the water you will also expel high levels of the critical minerals potassium, magnesium and sodium.

This may cause you to feel dizzy, lightheaded and tired.

We’ll talk more about specific supplements to replace these electrolytes below but you can also reduce the symptoms by eating certain foods.

The following are all good sources of potassium and magnesium. Be sure to season them well with sea salt to replenish your sodium levels:

Low blood sugar

If you’ve been eating a high carb diet then switching to a ketogenic diet is a big change for your body.

With all the carbs your body has been conditioned to release lots of insulin to process them. All of a sudden the carbs disappear and it may take your body a little while to catch up.

Again, there’s not much you can do to treat this but it is usually a temporary condition which will soon pass.

Sugar cravings

You will almost certainly crave sugar in the first few days and weeks following a ketogenic diet.

And these cravings can be strong!

It’s ironic that keto diets actually reduce cravings in the long run but this won’t help you a few days in when you’re dying for a sugary treat.

To help overcome the cravings be sure to have a few keto-friendly snacks at the ready.

Then when a craving starts do something to take your mind off it for a few minutes.

This is very effective. For example, one study53 showed that playing the computer game Tetris for 3 minutes reduced cravings significantly.

It’s not the computer game itself that’s responsible, any activity that requires you to focus will have the same effect.


As you will be expelling lots of water from your body you may experience dehydration. Dehydration is a major cause of constipation.

You can combat this by drinking lots of water and by eating lots of high fibre, non-starchy vegetables.


Whilst it’s the complete opposite of constipation, some people experience diarrhoea in the first few days.

Again, this is more common in people who had previously followed a high carb diet and it is simply your body getting used to the new way of eating.

A couple of teaspoons of psyllium husk powder mixed with a glass of water before meals will help to alleviate the symptoms.

Muscle cramps

If you become dehydrated you may also experience muscle cramps. The recommendations above for dizziness and drowsiness will also help with these.

A magnesium supplement can also be of use. Ensure you choose a chelated form and avoid magnesium oxide as this is poorly absorbed by our bodies.

Keto flu

The famous keto flu! It’s probably the most common and well-known side-effect.

“Flu” is a very appropriate name because the symptoms mimic influenza. They can include:

Water and electrolyte intake are (again!) the keys here. You may be able to avoid keto flu completely by staying hydrated and taking electrolytes.


This is another common side-effect at the beginning of a ketogenic diet.

In the long run you should sleep better on keto but the lack of carbohydrates in your diet may make it difficult for your body to produce serotonin, a key calming hormone released by our body at night.

Try having a snack of protein with a few carbs just before bed.

Halitosis (bad breath)

When your body goes into keytosis one of the keytones it will produce is called acetone.

Unfortunately, this has a smell similar to nail polish remover!

The good news is that it’s a sign things are working and your getting the benefits of the ketogenic diet.

But no-one wants bad breath!

To deal with it ensure you maintain good oral hygiene and try sugar-free breath mints.

As with many of the symptoms bad breath usually passes after a couple of weeks.

Heart palpitations

Although this can seem scary (and if you have any concerns you should, of course, get yourself checked out by a doctor), changes in your heart rate are often caused by low blood pressure.

And low blood pressure is usually caused by a lack of water and electrolytes.

Increase your water intake and consider taking the electrolytes discussed below.

Supplements for a ketogenic diet

Supplements are useful on a ketogenic diet for a few reasons.

First, they can treat some of the side effects.

They can also help plug gaps in your diet. For example, because the ketogenic diet doesn’t allow certain vegetables you may not get all the vitamins and minerals you need for your body to function optimally.

I’m not just talking about a multivitamin and mineral supplement here. Things like greens powders can be very useful.

Supplements can also help in a more positive way: they can speed up your progress towards your goals.

Omega 3s are a good example of this. Not only can they can help reduce inflammation they can improve mental sharpness and increase fat loss.

So, let’s take a look at the best keto supplements.


As we have seen, many of the side-effects of the ketogenic diet are caused by dehydration and electrolyte loss.

By electrolytes, I’m talking about important minerals such as potassium, magnesium, sodium and calcium. Each of these are critical to our bodies so would be wise to supplement with them, at least at the beginning of the diet.

By doing this you will avoid many of the side-effects listed above.

Vitamin D

Vitamin D may well be the king of keto supplements. In fact, it may be the king of supplements for health generally.

Having adequate vitamin D levels has been linked with a range of health benefits from preventing obesity54, heart disease55 and Parkinson’s disease56 to foetal brain development57 and blood sugar regulation58.

It is produced by our bodies following exposure to sunshine but as we now spend most of our time indoors around 50% of people are deficient.

On top of these benefits, it’s important on a ketogenic diet because it supports the absorption of calcium, magnesium and other minerals59.

The Vitamin D Council, a non-profit organisation that promote the benefits of vitamin D, recommends supplementing with 5,000iu of the D3 form each day.

MCT oil

MCT stands for “medium-chain triglycerides,” a type of fat that is not stored by our bodies but instead is used immediately the energy60.

MCTs also support keytone production helping us to reach and stay in keytosis more easily.

You can either take the pure form of MCT or you can use virgin coconut oil.

If you go for coconut oil ensure that it is “virgin. If it’s not virgin it’s unhealthy and should be avoided.

Omega 3s

You’ve probably heard of omega 3 fats and the health benefits of consuming them.

You may not have heard of omega 6 fats. In themselves there’s nothing wrong with omega 6 fats; they are known as an “essential” fat meaning that our body cannot produce them from other sources.

The issues arise when the balance between omega 6 and omega 3 intake becomes out of kilter.

As humans evolved we typically consumed a 1:1 ratio of omega 6s to omega 3s61. Today the ratio in Western diets is around 16:162.

The position is even more skewed than this ratio suggests because these fats compete with each other so the more omega 6s we consume the more omega 3s we need63.

So, what’s the problem?

When the ratio is out of kilter omega 6s cause inflammation and inflammation, as we have seen, is linked to numerous chronic diseases.

Excessive omega 6 intake has been linked with heart disease64, asthma65, cancer66 and depression67.

One issue with the ketogenic diet is that many keto foods are high in omega 6s so our requirement for omega 3s increases significantly.

To guard against our ratio getting skewed it would be wise to supplement with omega 3s.

Not only will they fight inflammation68 they will lower cholesterol levels69, reduce body fat levels and in particular belly fat70.

Taking omega 3s in the form of fish oil is the best option.

Go for 2,000mg of fish oil to give 700mg of EPA and 500mg of DHA each day. Look for products bearing a good IFOS (International Fish Oil Standards) rating to ensure you’re getting high quality.


Taking ketones in supplement form can help you reach ketosis and stay there71 72. This, of course, is critical to get the benefit of the ketogenic diet.

Ketone supplements (often called exogenous ketones) can:

They coming two main forms:

Ketone salts, a powder form that must be mixed with liquid before taking

Ketone esters, a liquid form

Both types are very effective in increasing ketone levels in our body. One study74 showed a 300% increase after supplementing with 12,000mg but the ester form is more difficult to come by.

Look for a ketone salt supplement that doesn’t contain fillers or additives, sugar or carbs and is made of beta-hydroxybutyrate (BHB).

Psyllium husk powder

Constipation and diarrhoea can be issues, particularly when first starting ketogenic diet.

Drinking plenty of water will help a lot but you can also add in a fibre product to help improve digestion.

Psyllium husk powder is a good choice here. Not only will it relieve symptoms of constipation and diarrhoea75, it will also help fill you up76 and balance blood sugar levels77. In doing this it encourages weight loss78.

Mix a couple of teaspoons of powder in water and drink prior to meals.

Digestive enzymes

Moving from a carb-heavy diet to a ketogenic diet can be quite a shock for your body and, specifically, your digestive system.

You’ll be eating much more fat – 70-80% of calories. That’s a lot! Because of this your digestion can suffer.

In fact, many people experience digestive problems in the first few days and weeks of keto. They usually pass but can be unpleasant to say the least.

If they are particularly bad or continue for a longer period you can take digestive enzymes to improve things.

Digestive enzymes will assist in the breakdown of fats and protein in your stomach which in turn relieves symptoms.

Look for a supplement that contains both lipase and protease enzymes for the best results.

Greens Powders

If you’re following the ketogenic diet to the letter you should be getting all the vitamins, minerals, phytochemicals and other micronutrients you need for your body to function optimally.

But (and it’s a big BUT!), following keto to the letter day in, day out can be hard and it’s easy to neglect fruit and veg.

This is an issue because these are what provide many of the nutrients we need.

If you struggle to eat sufficient fruit and vegetables then a greens powder supplement may be helpful. 

Greens powders are dehydrated vegetables ground into a powder that can be added to food or simply mixed with water. 

I’ll be honest, they don’t taste great and are not as good as eating fresh fruit and veg but they are better than not consuming them at all.

The ketogenic diet’s not for everyone

Whilst the ketogenic diet may be effective for some people it can be risky for others. Let’s have a look at the groups that should avoid it:

Athletes, active individuals and people looking to build muscle79: by implication the ketogenic diet demonises carbs. Not all carbs are bad, however, and for people with high energy expenditure they are a good thing, necessary even.

Protein is also important for these individuals and whilst modified versions of the ketogenic diet do provide higher levels of protein this is often not sufficient. Recovery is then impaired and progress stalls.

People with type 1 diabetes: type 1 diabetics require regular insulin injections to stabilise blood sugar levels. As one of the main effects of the ketogenic diet is to reduce blood sugar levels it may reduce them dangerous levels in these individuals80 81.

As we saw earlier, type 2 diabetics and people with Syndrome X may actually benefit from keto but, if you have either condition, you should consult your doctor before trying it.

Individuals with low willpower: keto is tough to stick with. It’s often a massive shift from previous eating habits and the huge reduction in carbs makes hunger a real issue until your body has adapted. This can take 2-3 weeks.

You need strong willpower to see it through.

A meta-analysis82 of 11 studies found that only 45% were able to stick to it. And these were people with a debilitating medical condition who were likely highly motivated.

Sufferers of eating disorders: the ketogenic diet is a strict eating regime and for people who have experienced eating disorders in the past the detailed focus on food could trigger a relapse83.

Individuals who’ve had their gallbladder removed: our gallbladder releases bile into our bodies and bile helps with fat digestion. With this being absent and the ketogenic diet being very high fat these individuals may not be suited to it.

Multiple sclerosis (MS) sufferers: the National Multiple Sclerosis Society has warned against the use of keto by MS patients. In particular, it has raised concerns about the long-term safety and the short-term side effects of fatigue and constipation. These are particularly problematic for MS sufferers.


If you want to lose weight the ketogenic diet will help you do just that.

It works and it works quickly.

But, keto is hard. Very hard.

Anyone who’s done it will tell you that the first few weeks are the worst and that’s true.

And though it does get easier, it’s still a very strict diet. 

It comes down to how badly you want the benefits. Do they provide sufficient motivation to help you ride out the tough times?

That’s a question only you can answer and you’ll never really know until you try it.

Of course, there are other options. Some, such as the Mediterranean diet, are easier to follow and, arguably, better and healthy than ketogenic diets. We’ll come back to this in another post.

For now, though, I’d love to hear about your keto experiences. Have you tried it? How did you get on?

Leave a comment below and let me know.


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About edge.unplugged

Hi, I’m James. I have a PhD in nutritional sciences and one of my biggest passions in life is nutrition. In fact, I’ve spent over 23 years studying it.

I wanted to create a site where I could help readers live a healthy and nutritious life. We control our destiny and we can choose to live a long and healthy life by treating our bodies with respect.

If that sounds like hard work, it shouldn’t. I’m only interested in simple, science-backed nutrition hacks that actually work.

You won’t find any fads here. Just easy to follow tips that give real-world results for people like you and me.