15 Typical Mistakes People Make on the Ketogenic Diet

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A Woman's Arm Holding An Egg In the Air.The ketogenic diet is controversial and does a great job of splitting opinion.

Some people believe the diet to be the optimal way for everyone to eat.

On the other hand, others feel that the diet is inherently dangerous (that isn’t true either).

The truth?

Keto isn’t for everyone, but it can have some impressive health benefits in those who follow it.

Just one caveat; these positive benefits are providing that the diet is well-researched and undertaken in a healthy way.

For this purpose, let’s look at 15 typical ketogenic diet mistakes and how to avoid them.

1. Not Drinking Enough Water

Girl In Exercise Clothes Opening a Bottle of Water.

Hydration is always important, but this is especially the case when you start a ketogenic diet.

When we restrict our intake of dietary carbohydrate, a whole lot of things happen inside our body.

One of these is that levels of circulating blood-glucose and insulin fall (1).

Now, consider that many people eating a standard Western diet have high levels of circulating insulin.

Why does this matter?

Because high levels of insulin cause the kidneys to store more sodium, which leads to the kidneys retaining more fluids (2).

Notably, as ketogenic diets strictly restrict carbohydrate, insulin levels fall within the first few days.

When insulin levels fall, our kidneys release these excessive amounts of stored fluids. If someone is not drinking enough water during this time, it can easily result in dehydration.

Many people starting keto for the first time complain of headaches in the first few days and, alongside electrolyte imbalances, this is one reason why.

Around a gallon of water during the early days of starting a ketogenic diet is a common recommendation.

However, no hard and fast rule is right for everyone.

Just make sure you’re drinking enough fluids, and monitor water intake based on thirst.

Key Point: Water requirements are higher during the first days of adopting a ketogenic diet. Not drinking enough water is a common mistake.

2. Not Consuming Enough Magnesium

As we just discussed, our kidneys flush lots of excess water from our body during the first stages of keto.

Unfortunately, that water will contain significant concentrations of sodium and electrolyte minerals – magnesium is one of these.

The resulting electrolyte imbalance can cause some collective symptoms that people often refer to as ‘keto flu’.

All minerals are “essential”, but magnesium has an extensive role in our body. In fact, it plays a part in more than 300 enzyme systems that are responsible for biochemical reactions in our body (3).

As a result, you can understand how flushing large amounts of this vital mineral out of our body can cause problems. Prolonged low levels of magnesium can cause symptoms of deficiency such as cramps, muscle tremors and eye twitches (4).

Getting Sufficient Magnesium

Some magnesium-rich keto-friendly foods include the following options;

  • Almonds
  • Avocados
  • Brazil nuts
  • Cocoa
  • Fish
  • Leafy greens such as spinach and swiss chard

It may also be worth investing in a good quality magnesium supplement if you aren’t sure you’re consuming enough.

Key Point: Magnesium is one of the most important nutrients for our health and we should ensure we replenish lost amounts of the mineral.

3. Neglecting Sleep

A Sleepy Woman Hugging Her Pillow.

This one isn’t exclusive to followers of the keto diet – it is crucial for everyone.

Not getting enough sleep jeopardizes our health in so many ways, and sleep quality is as important as our diet.

For example; some people opt to try a ketogenic diet as a way to better manage blood-glucose and insulin levels and possibly lose weight.

That is great, but if you are following a ketogenic plan and not getting enough sleep?

“Shooting yourself in the foot” comes to mind.

The reason why is simple; lack of sleep adversely affects blood-glucose levels, insulin sensitivity and even the lipid (cholesterol) profile (5, 6).

If you are using a ketogenic diet to improve these things, but then negatively affecting them through lack of sleep, then it is like taking one step forward but two steps back.

Sleep quality is extremely important whether you follow keto, paleo, vegan, or any other diet.

Don’t underestimate it.

Key Point: A healthy diet doesn’t overcome poor sleeping habits.

4. Not Eating Enough Fat

First of all, our body can use both carbohydrate and fat to meet its energy needs.

The whole idea of a ketogenic diet is to encourage our body to burn fat for fuel rather than carbohydrate. Therefore, if we cut down on the carbs, we need to increase our dietary fat intake.

However, some people who start ketogenic diets reduce their carbs but don’t replace this lost energy with fat.

One reason for this could be that people still feel a little uncomfortable about a high-fat intake. However, there is nothing to fear about natural sources of fat from foods such as dairy, fish, meat, and plant fats such as avocados and olives.

While protein can supply energy through the process of gluconeogenesis, it is an inefficient source in comparison to ketones (fat) and glucose (carbohydrate) (7).

Trying to live off protein and low-carb vegetables will quickly cause fatigue and a lack of energy, and ultimately make the diet unsustainable.

Key Point: Not eating enough fat is one of the most typical keto mistakes.

5. Ignoring Nutrient Density

Providing someone is eating low amounts of carbohydrate (<50 grams per day) and sufficient amounts of fat, it is technically a ketogenic diet.

However, this does not automatically mean this way of eating is healthy.

Like all diets, the respective health properties of a keto diet very much depend on the food choices you make.

In other words; a diet full of spam, hot dogs, processed ham, vegetables and soybean oil would be keto-friendly.

But it certainly wouldn’t be healthy.

On the other hand, a diet that emphasizes nutrient density ensures we have the requisite amount of nutrients to be healthy.

For instance, another keto-friendly day of eating may include oily fish, beef, cheese, eggs, leafy green vegetables, avocado, and extra virgin olive oil.

The macros would be similar to the first example, but it would also give us lots of essential nutrients and benefit our health.

Nutrient density matters a lot.

If you need help figuring out which foods are suitable for a ketogenic diet, see this keto diet food list.

Key Point: A keto diet can be good or bad for you depending on the foods you include.

6. Fearing Protein (Because of Gluconeogenesis)

A Diagram Showing the Process of Gluconeogenesis.

“You shouldn’t eat much protein because it will kick you out of keto”.

A common claim that some people repeat over and over, and yet it is not really based on science.

First, this idea comes from the fact that the process of gluconeogenesis can convert glucogenic amino acids (among other things) into glucose (8).

In simple English, this means that our body can turn protein into glucose.

This biological process is a protective mechanism that can help us survive in times of famine or food shortage.

For example, if we require fuel, then our body can convert amino acids (or lean muscle tissue) into glucose.

However, it isn’t simply a case of more protein = gluconeogenesis = more glucose.

Does Protein Intake Affect the Rate of Gluconeogenesis?

Yes, but not by as much as you would expect.

For instance, in healthy people, the process of gluconeogenesis is more demand-driven than governed by absolute amino acid availability.

Additionally, it is important to differentiate between metabolically healthy individuals and people with diabetes.

The amount of protein we eat does have a more substantial effect on blood glucose in diabetics, but not in non-diabetic individuals.

This increased conversion happens in individuals with diabetes due to hyperglucagonemia (high circulating levels of glucagon) (9).

How Much Protein Should I Eat?

The answer to this question likely differs from person to person and depends on activity levels, diet, and overall personal situation.

Personally, I think the easiest way is just to eat protein to satiety and follow our body’s natural cues.

Key Point: It is a common mistake for people to fear protein on lower carb diets. However, protein plays many beneficial roles in our body and the effect it has on glucose levels is over-exaggerated.

7. Eating the Wrong Types of Fat

Over the past few decades, bad science and media headlines drove home the message that we should severely restrict our fat intake.

That advice was wrong, and we now know that many dietary fats are beneficial and that the dangers of saturated fat were very much an exaggeration.

However, this doesn’t mean that all fat is healthy.

Yes, mayonnaise is an acceptable food choice for ketogenic diets, and many people do eat it.

But the main ingredient in commercial mayo is soybean oil, which is a highly unstable and easily oxidizable processed vegetable oil.

Such oils have links to a variety of problems including oxidation issues, negative effects on vascular function, and inflammation (10, 11, 12).

Just like overall food quality matters, so does the quality of the fats we include in our diet.

Whole food fats and naturally occurring oils from olives, avocados and coconuts are all reasonably healthy when used correctly.

On the other hand, it is better to avoid industrially produced fats such as margarine, vegetable oils, and trans fat.

Key Point: Opt for naturally occurring fats rather than industrially produced oils that are abnormally high in omega-6.

8. Keto Processed Food Is STILL Processed Food

Almond Flour In a Bowl Next To Whole Almonds.

Replacing a traditional cake recipe with one that uses almond flour, a sugar substitute sweetener, avocado oil/butter, and perhaps some flavorings is quite popular.

These keto recipes can allow people — particularly individuals with diabetes — to enjoy treats that won’t adversely impact their blood glucose levels.

This is a good thing and allows people the choice to try something that they wouldn’t otherwise be able to.

With the current popularity of ketogenic diets, many processed keto food options are appearing on store shelves now too.

And yes, they are a quick and convenient option and healthier than traditional processed foods full of sugar and refined flour.

However, we shouldn’t pretend this is health food. 

Combinations of processed flours and fats will never be as good for us as a whole-food based meal.

And this is the case whether a product is “keto” or not.

Key Point: Just because something is “keto” doesn’t mean it is healthy.

9. Not Fully Committing to the Low Carb Part

Some people start a ketogenic diet, increase their fat intake, and get by OK.

However, figuratively speaking, they still want to have their cake and eat it and end up consuming a high carb, high fat diet.

This eating pattern is a terrible choice for our health, and it is pretty much the standard American/Western diet.

If someone wishes to consume a diet high in fat, then carbohydrate intake should be relatively low.

Additionally, starting a ketogenic diet for the first time is notoriously difficult.

The adaptation phase can have some unpleasant “keto flu” symptoms, so starting and stopping the diet, again and again, is ill-advised and possibly dangerous.

Key Point: A sustainable ketogenic diet requires commitment. Starting and stopping over and over is not conducive to a healthy diet or good health.

10. Not Getting Enough Dietary Potassium

The Chemical Element For the Mineral Potassium (K).

As we discussed earlier, we lose large amounts of electrolytes when our body sheds fluid during the initial stages of a ketogenic diet.

One of the most important of these electrolytes is the mineral potassium, which has a crucial role in blood pressure, sodium, and water balance regulation.

This essential mineral also plays a part in bone mass density and muscle contraction (13).

Low levels of potassium may cause deficiency symptoms that include headaches, increased blood pressure and muscle cramps (14).

To ensure we adequately replenish lost potassium levels, we should focus on substantial dietary sources of the mineral.

Some foods that are especially high in potassium include;

  • Avocado
  • Cocoa
  • Mackerel
  • Salmon
  • Spinach
Key Point: Failing to replenish potassium levels is a common keto diet mistake. Notably, it is one of the biggest factors behind the so-called “keto flu”.

11. Restricting Salt Intake Too Much

Dietary salt intake is a controversial issue.

While excess salt consumption can have a negative impact on blood pressure, sodium deficiency may also be a risk factor for all-cause mortality and cardiovascular disease (15).

In other words, we need to find the right balance regarding our salt intake.

Significantly, in the first days of a ketogenic diet, people lose large amounts of sodium while their body discards excess water.

The Dangers of Excessively Low Sodium Levels

Such losses in this critical electrolyte can have side effects if the sodium is not adequately replaced. Some of these symptoms, such as dizziness, can be quite scary.

Furthermore, our body closely regulates sodium and potassium, so if we lose too much salt there will be a compensatory loss of sodium.

As a result of this, our absolute requirements for salt increase on a ketogenic diet.

Phinney and Volek, two of the most respected researchers on low carbohydrate science, recommend consuming between 3 and 5 grams of sodium per day on a very low carb ketogenic diet (16).

A few ways to get more sodium include liberally salting food, consuming salty soups and broths, and consuming fermented vegetables.

Key Point: Sodium requirements rise when starting a ketogenic diet – low levels of sodium can cause problems.

12. Not Considering Interactions With Health/Medical Conditions

A Doctor In a White Coat Holding a Noteboard.

Anyone with any health/medical condition whatsoever MUST discuss large-scale dietary changes with their primary care physician.

This situation is especially the case for individuals with diabetes who are on blood glucose-lowering medications.

For one thing, using a regular dose of insulin after starting a very low carbohydrate diet is dangerous and may result in blood glucose levels dropping too low.

Dangerously low blood glucose levels are known as hypoglycemia, and they can even cause loss of consciousness (17).

For this reason, insulin dosages would need careful titration to a safe and appropriate level.

The reason why dietary interventions work is because they are powerful and have a dramatic effect on how our biological systems and hormones operate.

In the event an individual has a medical condition, a ketogenic diet needs careful consideration, discussion, and planning.

Key Point: Significant dietary change need research and, if there is a medical condition to consider, it needs discussing with a doctor.

13. Bingeing on Fat

This point ties in with the section on nutrient density.

As priorly mentioned, not all fat is created equal, and there are good fats and bad fats.

However, even if we are talking about healthy fats, that doesn’t necessarily mean the more, the better.

For instance, some people consume hundreds of calories of butter and coconut oil mixed in their morning coffee. Every single day.

While this isn’t inherently harmful from time to time, it does replace more nutritious meal options, and these lost nutrients can add up if it is day after day.

Dietary fat is essential and it does have important health benefits, but isolated fats aren’t very nutrient-dense. Whole foods are where all the important nutrients are.

For instance, 500 calories of butter/coconut oil will provide lots of fat and a small amount of nutrients (18, 19).

On the other hand, 500 calories of salmon and eggs will provide lots of fat, protein, a vast range of vitamins and minerals and better satiation (20, 21).

Key Point: Consuming excessive amounts of isolated fat is one of the biggest ketogenic diet mistakes.

14. Caring Too Much About Ketones

Picture of Ketone Bodies - Acetone, Acetocacetate, and 2-Hydroxybutyric acid.

When our body burns fat for fuel, we will be making higher levels of ketone bodies (ketones).

Ketones are an alternative source of energy that our body can use for fuel and, in times of carbohydrate restriction, our liver produces them from fatty acids (22).

As a ketogenic diet relies on being in ketosis, many people like to see the level of ketones their body is producing.

However, although testing ketone levels using ketone strips may be exciting/interesting, it isn’t at all necessary.

In fact, many place too much emphasis on this level of ketones, and in truth, it doesn’t really matter.

Are you improving your health with a low-carb/ketogenic diet? Do you see visible improvements/weight loss?

That is what matters most – not a test score.

Key Point: We should focus on real markers of health rather than the number of ketones our body produces.

15. Not Researching a Ketogenic Diet BEFORE Starting

Ketogenic diets can have some very beneficial health impacts, but they can also have unpleasant side effects if they are “done” in the wrong way.

For this reason, it is imperative to fully research the diet and understand how to implement it in a healthy manner.

If anyone is considering starting a keto diet, then hopefully this article has given some basic pointers that need consideration.

However, no-one should start a ketogenic diet without being fully aware of the science, benefits and drawbacks.

To give the best possible chance of dietary success, it is worth absorbing all the information you can before making a decision.

Key Point: Ketogenic diets have a large impact on the way our body operates and they require careful research.

Final Thoughts

Ketogenic diets are probably not the right fit for everyone, but they can have some great benefits if they are correctly implemented.

To follow a keto diet in a healthy way, it is important to research the diet thoroughly before starting.

Careful research will allow you to avoid these typical keto diet mistakes.

For more on the ketogenic diet, see this guide to combining intermittent fasting and keto.

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I started Keto three months ago and have lost 45 lbs. Unfortunately, I still have around 80-85 lbs to go and have hit a plateau for the last three weeks. I drink “cognitive” coffee in the morning with butter and MCT which holds me to about noon. I eat two meals consisting of various proteins (sea food, beef, pork, and poultry) and green veggies for approximately 10-15 carbs and 1,000 – 1,500 calories a day. I recently upped my calories to see if that would help to no avail. Any thoughts?


Try intermittent fasting! I’ve done keto wrong for the last 2 year’s but managed to drop 30 pounds and hit a plateau I just couldn’t get thru. About 4 weeks ago I decided no more processed meats. I was all about bacon and salami. Heavy cream and sugar free hazelnut in my coffee…because there was a time I thought that was the ONLY way I could enjoy coffee! Now enjoy my coffee black with mct oil. I make coconut oil based fat bombs for snacks and sweet cravings which I haven’t even had much lately. More nuts too. And I… Read more »


45 lbs is a lot, congrats! I suggest to try calculating or recalculating your macros for weightloss, and using a tracking app like Carb Manager or MyFitnessPal to accurately track your adjusted macros daily. Being at a lower weight now, your body has different needs to lose more weight. Experts typically advise to do this once you have hit a plateu / weight loss stall of at least 3 weeks or more.


I am 120 pounds overweight. I have been told that because of my weight I should not have 70% fat until a large amount of weight is lost. Then a read something different. How much fat do I need?


My husband was very successful on this and has been wanting me to try it, however, I am a little apprehensive due to my recent cholesterol screen shows my overall as a little high, are there any positive results for lowering?


I have been on a ketogenic diet for 3 months. When I started, I supplement with 500 mg Magnesium and 2,100 mg Potassium every day while consuming minimal Sodium at 2,000 mg. I did not get the Keto Flu. I drink 2 liters of water and my carbohydrates come mainly from leafy green vegetables and some nuts and seeds. My calories deficit per day is 800 calories and I have lost 21 lbs in 3 months. My body fat percentage went down from 25% to 14%. I think sodium at 4 to 5 grams is too much. My blood pressure… Read more »

Joanna Grundman
Joanna Grundman

Very informative and easy to understand. I justed started it myself. I am excited to get it going.

Ellen Fortune

This was such a helpful article. I am on day 7 of the Keto diet and feel pretty good. I am having fun looking up recipes and trying them! Every now and then I will drink a Propel Zero if I feel I haven’t had enough magnesium. So far no Keto flu symptoms. I use the Crb Manager app to track. I think tracking is helpful mostly so you know you are getting enough fat & protein. I have hyperthyroidism and take synthroid daily. Hopefully this won’t mess any of that up….


Been on keto for 3 weeks now.
Today I became dizzy and felt as if I was going to pass out.
I went and bought a power aid drink and drank half of it. Dizziness became a little better.any suggestions?


I started the Keto/low carb diet and did experience the “Keto flu” which was only for one day. While I’m trying to stay away from alcohol I was drinking vodka seltzer over the weekend and when I checked my ketone levels with the sticks it still said I was in ketosis. Anyone know if vodka seltzer is generally “acceptable” to drink while still trying to be in ketosis (according to the urine strips)


Great information here! I’ve adjusted to a ketogenic lifestyle over the past 4 weeks. I have followed the guidelines very strictly while having fun figuring out what meals I can plan and what foods make me feel better. The greatest impact it has made for me has been the deletion of leaky gut with IBS. Keto has helped me flush the bad bacteria in my stomach and allowed good bacteria to flourish simply because the bad bacteria feed on the carbs. Once I inflated my fat intake with the right fats I suddenly noticed all symptoms go away like, bloating,… Read more »


Thanks. That was very helpful. I am gearing up to start in May and I made a note of all of these suggestions and I have some studying to do as per your suggestion. Your information will be a big help to my being able to successfully implement this lifestyle change. I have one copy of the ApoE4 gene so I will be carefully navigating the proper amount of fat while keeping carbs very low. At first this sounded frustrating and almost impossible, but I think I can do it and not worry too much about counting anything. I’ll just… Read more »