How to Build Muscle on Keto: The Complete Guide

Key Points:

  • The ketogenic diet is low-carb, high-fat diet. It’s effective for weight loss, and you probably don’t have to count calories.
  • You can expect to perform as usual during exercise on a keto diet, but building muscle might be a bit more difficult than if you eat carbohydrates.
  • Keto appears safe, although the side-effects the first weeks are unpleasant.


The ketogenic diet is not any old low-carb diet. The ketogenic diet is just as much a high-fat diet as it is a low-carb diet. A standard ketogenic diet provides about 80% of your calories as fat and less than 5% as carbohydrates.1 2

You might be wondering if keto is a viable diet for building muscle.

  • The ketogenic diet is not usually a high-protein diet, but we all know that if you want to see muscle growth, you need to keep your protein intake high. How do you manage that equation?
  • In addition, the traditional fuel for high-intensity exercise is carbohydrates. Can you perform in the gym if you eliminate them from your diet?

All legitimate questions, for sure. Don’t worry, though. I’ve got the answers to them and many others.

In this article, you will learn everything you need to know if you’re going keto.

I’ll cover everything about keto, how it helps you lose body fat while keeping lean mass, and if the ketogenic diet is good for building muscle. Also, you’ll find some easy-to-use practical tips you can use in your diet and training.

Bring on the bacon!

First a Little Background and History

You might have heard about the ketogenic diet as a weight-loss method. That’s probably how most people first come into contact with it. However, the ketogenic diet was developed as a method to treat epilepsy once upon a time. 

During the early 1920s, researchers discovered that a diet with very few carbohydrates and a lot of fat successfully helped children with epilepsy control their condition. In 1925, doctors found that almost all patients reduced their symptoms, and 50% of their epileptic seizures went away completely on a ketogenic diet.3

When seizure medications were introduced, the ketogenic diet as an epilepsy treatment faded into obscurity. Lately, it has made a comeback when medications alone won’t do the trick.

Keto as a way to lose weight became popular during the 1970s, with Robert Atkins’s book Dr. Atkins Revolution. The book described various diet plans based on the low-carb diet he used to treat overweight patients. The book became a best-seller, with movie stars and other celebrities embracing the diet. Physicians and scientists weren’t as impressed, condemning it and the methods Atkins described as scientific nonsense and potentially harmful.4

At first, the diet didn’t become as popular as Atkins probably desired and even expected.

Not until 1992 did Atkins get his revenge. That’s when the new, revised version of his book, called Dr. Atkins New Diet Revolution, was published. It quickly entered the New York Times best-seller list and parked there for more than six years.

That book is one of the significant factors that made low-carb diets as popular as they are today. During the 1990s and into the 2000s, low-carbohydrate diets became the most popular and widespread weight loss methods, including the ketogenic diet.

In recent years, the ketogenic diet has gained popularity with athletes, too. Several studies show that a ketogenic diet works even for high-level athletes.

That’s quite the turn-around from earlier decades when most people and even sport scientists thought high-level athletics was nearly impossible without eating many carbohydrates.

How Does Keto Work?

The primary purpose of a ketogenic diet is to get you into ketosis. Ketosis is a metabolic state where you don’t have a lot of glucose in your blood. Starvation leads to ketosis, but that’s not what we’re talking about here. The ketogenic diet is when you deliberately avoid carbs to get the benefits of ketosis.

When you remove carbohydrates from your diet, your body fat releases large amounts of fatty acids. Your liver uses these fatty acids to produce ketone bodies. Your body and your brain can then use them as fuel instead of glucose.

It takes a while for your body to get used to the fact that you’re no longer giving it any carbs. You might notice that both your body and your brain won’t function as usual during this time. You can feel tired, get a headache, and feel nauseous. 

Once you’re past this “keto flu,” which usually lasts a few weeks, your muscles and brain adapt to the new fuel and learn to use the ketone bodies much more efficiently. That means that you can function normally during daily life and exercise again. 

Your brain never stops using glucose to fuel itself entirely, but your liver can make that amount on its own, even when you don’t eat any carbohydrates. 

Is Keto Effective for Weight Loss?

No one can deny the popularity of low-carb diets when it comes to weight loss. However, the average low-carb diet isn’t a proper ketogenic diet. You get too many carbs to enter ketosis, and the fat content isn’t always very high.

Mainstream media has helped popularize going low-carb as an effective way to lose weight. Sometimes, you forget about calories and focus on carbohydrates alone.

Every diet that makes you lose weight reduces the number of calories you eat and creates an energy deficit. The ketogenic diet is no exception.

Several large-scale studies examine the effects of low-carb and ketogenic diets and how effective they are for losing weight.5 6 The results show that low-carb diets are at least as effective as low-fat diets. One study demonstrated that the Atkins diet is just as good as low-fat diets, calorie-restrictive diets, and regular low-carb diets. Also, keto improved cholesterol levels and insulin kinetics the same way the other diets did.

A meta-analysis from 2013 with around 1,500 subjects found that a long-term ketogenic diet leads to greater weight loss than a low-fat diet.7 However, the differences were minimal compared to a high-carbohydrate diet with the same number of calories.

Keto is probably not superior to other types of diet with more carbs but the same number of calories. However, if weight loss is what you’re aiming for, going keto by avoiding carbs seems to be at least as practical as counting calories.

In the end, you can’t get around the fact that calories in vs. calories out drives weight loss. You have to eat fewer calories than you expend to lose weight, whether you eat a high-carb diet or a ketogenic diet.

Many find that they don’t have to keep track of every single calorie with a ketogenic diet. Not a bad thing! Instead, the food intake regulates itself, resulting in automatic weight loss.

A diet rich in fat makes you feel full and reduces your appetite by releasing several hormones.8 9

  • Peptide YY, or PYY for short, is a gut hormone that reduces appetite and makes you feel full.10
  • Glucagon-like peptide 1 (or GLP-1) is an intestinal hormone that regulates insulin release and keeps your food intake in check. It also slows down gastric emptying, making you feel full longer.11

They work together to inform your gut and brain that you are full and don’t need to eat more.

Also, a diet with a lot of fat makes food travel more slowly through your intestines because of the fat itself and the previously mentioned hormonal signals.

Carbs don’t promote feelings of fullness to the same extent. That makes the ketogenic diet a good choice for weight loss without having to count calories.

Some claim that you lose weight regardless of calorie intake because you don’t eat carbs and have lower insulin levels. There is no evidence for that notion. Strictly controlled trials demonstrate that a ketogenic diet does not have any such advantages.12

You burn a few more calories when you’re on keto because you convert protein and fat to fuel instead of using glucose directly.13 That’s such a small number of calories that it is unlikely to have any meaningful effect on your body weight in and of itself.

A recent review from the National Lipid Association (an organization seeking to enhance the knowledge and practice of lipid management in clinical medicine, not an industry organization for cooking oils, as the name might imply) confirms that eating few carbs helps with your appetite during a diet. It also concludes that there isn’t any evidence that ketogenic diets are better for losing weight than any other methods.14

In summary: low-carbohydrate diets and ketogenic diets are good for weight loss. No scientific evidence shows that they are superior to a mixed diet that provides the same amount of calories.

Instead, ketogenic diets help you control your hunger and suppress your appetite. You eat less without having to count calories. Many people find that it leads to weight loss with little effort.

Read more: How to Cut: Lose Fat and Keep Your Muscle Mass.

Exercising on the Ketogenic Diet

Forget outdated claims that you need to pound down the carbs if you train hard. Modern research shows that you can perform well without them on a ketogenic diet.

Endurance Training on Keto

When you cut carbs from your diet, your body learns to use fat instead. Your muscles rely more on fat as fuel during training when you’re on a ketogenic diet.

When you’re on a ketogenic diet and give your body enough time to adapt to it, your fat burn twice as much fat during exercise as when you eat a regular high-carb diet.15

A study from 2018 showed that cyclists, runners, and triathletes on a keto diet use far more fat during training than usual.16In that study, the keto group also lost more body fat and even improved their performance compared to a control group.

Some fans of keto would tell you that it’s superior for improving performance during endurance training. However, research does not support such claims.

A few studies show small improvements in performance and endurance, but they are the exceptions rather than the rule. For the most part, athletes on a keto diet seem to maintain their performance levels.17 18 19

There are also studies where the subjects experience performance decreases when cutting the carbs from their diets.20

One of the most common objections to keto studies looking at exercise performance is their short length. It probably takes more than a couple of weeks for the potential benefits of keto-adaptation to appear.

Sadly, there aren’t a lot of long-term studies available. One study with keto-adapted ultra-marathon runners and Ironman Triathlon competitors showed that their fat oxidation more than doubled after 20 months.21 Unfortunately, the researchers didn’t measure if they performed any better because of that. In any case, they were elite athletes, placing very high both in national and international competitions, both before and after going keto. That shows that it is quite possible to perform at a very high level without relying on carbohydrates.

In a recent study, runners followed a diet consisting of either 43% carbohydrate and 36% fat, or 4% carbohydrate and 78% fat during a month of training. Performance tests showed that their endurance capacity didn’t decrease on keto, as long as they didn’t go all-out in their workout. However, when training at a high intensity, they couldn’t maintain their training efficiency.22

In summary: if you train with a low to moderate intensity, you shouldn’t have any problems performing well on a ketogenic diet. However, no scientific evidence supports replacing carbs with fats to perform even better. 

Recent research shows that a ketogenic diet is neither good nor bad for physical performance.23 And that’s a good thing. It means you can eat the way you like without losing out on your training.

Strength Training on Keto

There aren’t as many studies on the effects of ketogenic diets on strength training as endurance training. Research suggests that you don’t have to worry about performance, at least in the short term. On the other hand, a diet without carbohydrates might not be the best choice if your training goals max muscle growth.

Several keto studies focus on CrossFit-athletes.

One study followed 12 non-elite CrossFit subjects who continued eating their normal diets or switched to keto during three months of training. Those who eliminated carbs lost more body fat without any decrease in running or strength performance. However, they lost muscle mass in their legs. The subjects eating carbohydrates didn’t lose any muscle mass.24

In another study, 27 male and female CrossFitters ate either their usual foods or max 50 grams of carbs a day for six weeks. During this time, the low-carb group lost more body weight and several kilograms more body fat than those eating their normal carbohydrate-rich diet. All subjects improved their exercise performance, and both groups did it without losing any muscle.25

When it comes to traditional strength training, a 2017 study looked at the effects of keto on body composition, strength, and hormone levels. The subjects? Twenty-five trained men ate either a standard western diet (20% of the calories from protein, 55% from carbohydrates, and 25% from fat) or a ketogenic diet. Both groups increased their fat-free mass during ten weeks of training, but the non-keto group gained significantly more. Both groups also lost body fat, but the keto group lost the most. All subjects increased their strength similarly regardless of diet, but the keto group also increased their testosterone levels.26

One recent keto study looked at powerlifters and Olympic weightlifters at different levels, from amateur to elite. During a 6-month study, they either ate their usual diets, providing more than 250 grams of carbohydrates per day, or a ketogenic diet with less than 50 grams of carbohydrates per day. The study was a crossover trial, meaning the subjects followed one diet for three months before switching to the other diet for the remaining months. During the ketogenic phase, the lifters lost weight, more than half in the form of fat-free mass. Despite this, there was no difference in performance depending on diet, and they could lift just as heavy regardless of carbohydrate intake.27

Finally, let’s take a look at a small-scale study featuring elite gymnasts from 2012. After a month almost completely without carbohydrates and a calorie intake below 2000 calories per day, the participants lost body weight and fat. At the same time, they had managed to increase their fat-free mass a little. Three months later, the same gymnasts ate a standard western diet, providing around 50% carbohydrate, for the same amount of time. During this part of the study, their body composition didn’t change. In other words, neither of the diets affected their strength or performance.28

In summary: most studies show that you can expect to perform just as well in the gym without carbs as with them. Even for high-level lifters, keto works fine for strength training.

On the other hand, keto might not be the best option for building muscle.29 30 31 32

Some studies show that keto could be similarly effective as a high-carb diet, though.33

On a weight-loss diet, keto might help protect your hard-earned muscle, but in general, keto is probably better for maintaining muscle mass than increasing it.

You can build muscle on keto, but perhaps not as easily as a high-protein diet with more carbs.

Protein Intake on Keto

If you strength-train regularly, you probably know the importance of protein. Eat too little protein, and you make gaining muscle mass and strength more difficult. A high-protein diet is crucial for stimulating muscle protein synthesis and growth.

A common concern is whether or not a high protein intake might prevent you from entering and remaining in ketosis. It’s a valid question. Fortunately, your training gives you several advantages.

Your liver converts protein to glucose when you limit your carb intake.  That process is called gluconeogenesis.

In addition, you release insulin when you eat protein, just like when you eat carbs.34 When you’re on a keto diet, you convert a little more protein to glucose.35

You don’t use that close as fuel right away. Instead, you store it as muscle glycogen without eating carbohydrates. Muscle glycogen is important for performance and recovery. In other words, you don’t have to give that up, even though you don’t eat carbs. You don’t store muscle glycogen as effectively as if you had carb-loaded after a workout, of course, but you still get some of the benefits of carbs without eating them.

It also means that you can remain in ketosis despite a high protein intake. Your muscles use ketone bodies for energy. They don’t need the glucose you get from protein. That glucose ends up as muscle glycogen instead, and you remain in ketosis. Everybody wins.

How Much Protein Can You Eat and Still Be in Ketosis?

A standard ketogenic diet isn’t rich in protein. That’s perfectly fine for the average person who doesn’t weight train for maximal muscle mass. If your goal is gaining strength and building muscle, though, a low-protein diet won’t cut it.

So, how much protein can and should you eat?

Protein doesn’t have much of an effect on blood glucose.36

That means you can eat a lot of protein without worrying about your blood sugar spiking and bringing you out of ketosis.

The fat you eat releases almost no insulin at all, and you have already minimized your intake of carbohydrates. That leaves protein, which does cause insulin release.

How much protein you can eat before that release kicks you out of ketosis differs from person to person.

For one thing, genetic differences determine how sensitive you are to insulin and how efficiently you use ketone bodies as fuel. Also, the better shape you’re in, the more protein you can eat and remain in ketosis. Your body doesn’t need to release as much insulin to deal with the protein you eat and transport it to its intended destination and purpose.

The best way to make sure is to measure your blood ketone levels. That means that you will have to go out and buy a blood glucose meter that can also measure blood ketones. Such a device for consumer use isn’t costly at all.

When you have your blood glucose/ketone meter, start by restricting your carbohydrate intake enough for ketosis. Limiting your intake to 20 grams a day for a week should be low enough.

During this time, eat as much protein as you are shooting for, say 1.6 to 2 grams per kilogram of body weight and day. That’s a great amount of protein for building muscle.37

Test your ketone levels using the blood glucose meter. If they are at one mmol/L or above, you don’t have to make any changes. You have found the protein intake you can eat and remain in ketosis, as long as you keep your carb intake down. 

If your blood glucose meter shows ketone levels below one mmol/L, and you are sure that you haven’t been eating more carbohydrates than intended, you’ll have to lower your protein intake a bit. Gradually reduce it by 10 grams at a time until your blood ketone levels go above one mmol/L.

Once you have found the highest protein intake that lets you stay in ketosis, you’re good to go. You don’t need to check your ketone levels more than once a week or so. Just do it now and then to make sure you’re on track.

If the idea of fiddling with glucose meters and measuring ketone levels, you can just wing it. Eat 1.6 to 2 grams of protein per kilogram of body weight and day and hope for the best. With any luck, you’ll be in ketosis without any issues. Just keep in mind that you could be off with this method. 

In summary: you don’t have to follow standard protein recommendations for ketogenic diets. When you weight train and have more muscle than average, you can eat quite a lot of protein and still reach and remain in ketosis. 

If you want to make sure and not leave anything to chance, you can use a blood glucose meter with the capability to measure ketones to do so.

Read more: Protein for Strength Athletes and Bodybuilders


Are ketogenic diets safe? Can you stay in ketosis long-term without health issues?

That’s where science fails to provide us with any certain answers. Not because of any particular suspicions of harm, but because there isn’t any real long-term data available. We can say for certain that a short-term ketogenic diet is not harmful. If anything, shorter cycles of ketogenic dieting seem to be great for both your brain and body.38

A 2004 study showed no negative effects of staying on a ketogenic diet for two years.39

Of course, two years is kind of a short-term study in this instance. For a diet to be considered safe, you have to be able to stay on it your entire life without negative consequences. Unfortunately, controlled studies longer than two years are nowhere to be seen, at least not yet.40

Some researchers and doctors advise against the ketogenic diet, arguing that we don’t know the long-term effects. On the other hand, other experts recommend keto based on short-term health benefits and because carbohydrate is not a physiological necessity. Both sides have their champions, but currently, neither side can guarantee long-term safety or show any concrete evidence of harmful effects. 

Millions have used the ketogenic diet for years and years. So far, there is no convincing evidence that their health has suffered from it.

Documented negative side-effects of a ketogenic diet include kidney stones and deficiency of specific vitamins and minerals. The latter is probably caused more by a poor or uneducated choice of foods than ketosis itself.

When you start a ketogenic diet, you most likely will experience several adverse effects. These aren’t harmful, but they can be pretty unpleasant. Unpleasant enough that many discard the diet before they have adapted to it. 

Some side effects include fatigue, dizziness, nausea, decreased physical and mental performance, trouble concentrating, and difficulty falling and staying asleep. Also, some people experience vomiting, constipation, and headaches. These effects pass after a few days to weeks. Your brain and body get used to being fueled by ketones instead of glucose.

If you switch from a mixed diet ketogenic diet, the most significant risk is probably nutritional deficiencies. In general, animal foods give you just as many or more micro-nutrients as plant-based foods. However, if you switch over without doing proper research, you might end up with an imbalanced diet. 

A ketogenic diet doesn’t have to be nutritionally poor, but you need to read up on eating diverse enough to cover all your needs. In general, it is a more restrictive diet than most, after all.

A diet with a poor fatty acid balance, too much salt, and various additives like sodium nitrite could have health consequences. On a ketogenic diet, your intake of these things could increase quite a lot, depending on what you eat. Most likely, the majority of the reported health consequences of a ketogenic diet are from a poor choice of foods rather than any adverse effects of ketosis itself.

In summary: eating a ketogenic diet can result in several documented short-term side effects. These are unpleasant but harmless and pass within a week or two. Whether or not a long-term ketogenic diet can impact your health is unclear, but nothing suggests that this is the case.

Practical Applications

First of all, how should you adapt your strength training for a keto lifestyle?

You shouldn’t. One of the selling points of the ketogenic diet is that you can live your life, as usual, but without carbs. A training program for building muscle looks the same whether you’re on a ketogenic diet as a high-carb diet.

  • Practive progressive overload in your training. Always try to increase the weight you use or do a rep more with a certain weight.
  • Anything between 3 and 30 reps works for building muscle. From a practical standpoint, 6–15 is a good starting point. Always going heavy taxes your joints, and high-rep training to failure is mentally exhausting.
  • You should perform at least 10 sets per muscle group and week if you want optimal results in the form of muscle growth.
  • It doesn’t matter much if you work a muscle once or five times weekly, as long as your total weekly training volume is the same. If you’re into high-volume training, you benefit from spreading your training volume over several workouts. Otherwise, the quality of your sets might suffer.
  • Rest two minutes or longer between sets.
  • Include a variety of exercises to target your muscle from different angles, and mix and match compound movements and isolation exercises instead of relying solely on one or the other.

Those are essential strategies for maximizing muscle growth.41 Keep them in mind, and you’ll build muscle, regardless of how you eat, as long as you eat enough.

So, what do you eat on a ketogenic diet?

This part of the article provides you with a few concrete tips on how to compose your ketogenic meals. You won’t find any detailed measurements in grams here. Instead, you have to adjust your meal sizes and their energy content on your own, based on your requirements. A ketogenic diet is nothing special in that regard. You still need an energy surplus to gain weight and an energy deficit to lose weight.

You don’t have to base your diet on bacon and eggs just because you’re doing keto. Of course, everything’s better with bacon, but don’t base your entire diet around it.

Here are a few examples of complete meal suggestions that can be a part of a healthy ketogenic diet. These meals are rich in nutrients, and hopefully, they sound appetizing as well.

Mackerel in tomato sauce with scrambled eggs, a green salad, and fresh tomatoes

  • Ground beef patties with onions and gravy, and oven-baked root vegetables
  • Cauliflower pizza with mozzarella cheese and bacon
  • Oven-baked salmon with parmesan cheese and cream, on a bed of spinach
  • Meatloaf made with cream and eggs + brown gravy + green string beans
  • Chicken thigh casserole with creamy sauce and mixed greens

Kitchen Essentials

Make sure you have these foods and ingredients in the fridge, freezer, or pantry, and you will never find yourself empty-handed when it’s time to whip up a meal.

  • Fish and seafood. Both canned goods like tuna, mackerel, and sardines, and fresh or frozen fish like salmon are healthy and muscle-building food. Of course, you can eat lean fish, but then you’ll need another source of fat as well.
  • Meat, including both red and white meat. Beef, pork, lamb, game, chicken, turkey, and so on. Don’t be afraid of the fattier cuts. On the contrary, these are often the better choice for a ketogenic diet, and often the tastiest and cheapest, too.
  • Low-carb vegetables, fruits, and other plants. Fibrous vegetables without too much starch can and should be part of your diet. Broccoli and cauliflower are low-carb enough that you can include them as part of a ketogenic diet, in moderate amounts. Spinach, arugula, asparagus, cabbage, cucumbers, tomatoes, kale, and bell peppers can be used without any particular restrictions. Try to pick a wide variety of colors. Differently colored vegetables contain different micronutrients and antioxidants. Avocado and olives are two fatty fruits that are popular amongst keto-fans for a good reason.
  • Nuts and seeds. All kinds of nuts, seeds, and almonds are a great addition to a keto diet. They are low in carbs and high in fat and protein. The fat is of varying quality depending on the nut, and the protein doesn’t have the best amino acid composition, but as a part of your diet as a whole, they are valuable and provide both energy and nutrients.
  • Eggs. The most complete single food there is. Perfect both as a main dish and in cooking.
  • Dairy products. If you aren’t intolerant to dairy, milk products give you access to the most muscle-building proteins of all. Full-fat dairy products are associated with cardiometabolic health.42
  • Milk, cottage cheese, curd, quark, hard and soft cheeses, yoghurt, and butter are rich in either protein or fat, or both, and in most cases also provide plenty of calcium.
  • Fats. Olive oil, rapeseed oil, nutty oil, avocado oil, coconut oil, and good old butter are pure fat sources suitable both for cooking and for adding to any recipe to increase the fat content.
Avocados and cheese are staples in a keto diet.

If there is one thing you probably shouldn’t over-indulge in, it’s processed meats: bacon, ham, salami, sausages, and various packaged lunch meats. Not because they are nutritionally worthless, but because they are associated with colorectal cancer. The World Cancer Research Fund and the American Institute for Cancer Research report that processed meats cause cancer in humans.43

Several mechanisms could be responsible, but heme iron and sodium nitrite used as a preservative and coloring agent are the most probable. Sodium nitrite is classified as “probably carcinogenic to humans” by The International Agency for Research on Cancer

In other words, it might be a good idea not to rely too heavily on processed meats.

Supplements for the Keto-Adapted Athlete

Your diet is always the most crucial factor, but some dietary supplements can help you boost your performance and health.


No supplement is backed by more research than creatine. Creatine helps you perform better, become stronger, and gain more muscle.


Caffeine is a great pick-me-up and a tried and true energy boost for high-intensity training sessions. It won’t kick you out of ketosis, either.

Exogenous Ketones

In addition to the ketones your body produces when doing keto, you can also provide it with extra ketones with an exogenous ketone supplement. It lowers your appetite and even improves your exercise performance.44 45

Protein Supplements

A quality protein powder, like whey, casein, or soy protein, is always good to have at hand if you need a convenient and non-expensive way to boost your overall protein intake.

Read more: Whey or Soy Protein for Building Muscle?

MCT Oils

Your liver breaks down MCT oils, and your body can then use them as energy. They allow you to eat more carbs and protein and still stay in ketosis and is a helpful tool to up your fat intake on a ketogenic diet.46

Keto FAQ

Here’s some common questions about keto not directly covered earlier in the article, with answers.

I’m Feeling the Keto Flu? How Do I Get Rid of It?

When you go keto, it takes some time for your body to adapt to the lack of carbohydrates in your diet. Many feel awful during this time, which can last for up to four weeks or so. It’s often called “the keto flu.” It’s not an actual disease, and you’re not really sick, but it sure can feel like it.

Since this is not a medical condition, it’s not described in the medical literature. It’s probably caused by several factors, most notably low sodium levels in combination with dehydration and your brain not getting its usual fuel.

Keto lowers your insulin levels, which is a good thing, but low insulin levels also make you retain less sodium. 

Carbohydrates stored as glycogen retain a lot of water, so when your glycogen stores decrease, you also lose plenty of water.

While you probably can’t skip this transition period altogether, you can mitigate the adverse effects.

Be sure to drink enough water. Don’t gulp it down by the gallons, but don’t go dehydrated. Drink enough to satisfy your thirst and a little extra during and after exercise.

Don’t eat a low-sodium diet. While cutting down on sodium might be a good idea for someone eating a standard western diet, you’re already losing a lot of sodium when you start a ketogenic diet. During the first weeks of keto, I suggest you get at least 5 grams of sodium per day to mitigate that. Add some salt to the foods you eat.

If you’re active and exercise a lot, you could also add potassium and magnesium to your regular diet. I’d suggest 200–300 mg magnesium and 500–1,000 mg of potassium in addition to the amounts you get from foods. These amounts have no adverse effects and will ensure your body has enough during these taxing weeks.

I’m Not In Ketosis Anymore! How Do I Get Back?

It’s easy to get kicked out of ketosis if you don’t watch what you eat carefully. Even a small amount of hidden carbs can do it. Your body will choose to be fueled by glucose if you make it available.

Don’t worry, though. It’s just as easy to get back into ketosis. Just get back on your regular ketogenic diet, and things will take care of themselves.

If you want to speed things up, you can go on a short-term fast for some hours or add ketogenic fats, like MCT oils, to your diet. If you’re really in a hurry, you can use a supplement with ketogenic esters, but that feels like going overboard. 

Nothing terrible will happen if you’re out of ketosis for a few hours.

Can I Combine a Ketogenic Diet with Intermittent Fasting?

Sure you can. In fact, intermittent fasting is a good way to get into ketosis faster and to increase your ketone levels more.

Keep in mind that intermittent fasting + a ketogenic diet can make the initial keto flu worse. You might want to get past that stage before incorporating IF into your keto lifestyle, at least unless you’re already used to it. It’s not dangerous, so try it if you want to.

If you’re taking diabetic medications, you should check with your doctor before trying this combination. It could result in glucose- and insulin fluctuations your medication isn’t dosed for.

I’ve Been on Keto for a While, But I’m Not Losing Weight. What’s wrong?

Keto might be marketed as a sure-fire weight-loss method, but this doesn’t have to be the case. You can lose, maintain, or even gain weight with the ketogenic diet.

The basic calorie in minus calorie out-equation still holds. You need to burn more calories than you eat to lose weight, even when you’re doing keto.

Many people automatically eat less on keto. So much so that they lose weight without thinking about calories. But not everyone does.

Double-check to ensure you’re really in a calorie deficit if you’re using the keto diet to lose weight. If you’re 100% sure you are, look at things like stress and medications, which can cause water retention, masking weight loss.

I’m Vegan/Vegetarian. Can I Still Do Keto?

It’s theoretically doable, but it would probably be a serious challenge. A vegan diet provides few “pure” protein sources. You often get carbs along with your protein-rich foods. Probably too many carbs. Getting enough protein on a vegan diet isn’t hard at all, but doing so while keeping carbs below 50 grams a day is. You’d likely have to rely quite a lot on protein supplements for protein.

It should be possible if you’re a lacto-vegetarian or a lacto-ovo-vegetarian (you use dairy or dairy and eggs). But I’m not sure it’s worth the effort if you’re eating a vegan diet.

Can I Drink Alcohol When I’m on the Ketogenic Diet?

Yes, but you need to keep some things in mind.

You might get kicked out of ketosis if you drink alcohol. You’ll re-enter ketosis automatically, but if you want to stay in ketosis uninterrupted, you’d do best to stay away.

If you want to drink alcohol, choose a drink without a lot of carbs. Beer and cocktails will take you out of ketosis for sure. Spirits, dry wines, and champagne are better choices.

Also, you might find that alcohol hits harder than usual when you’re in ketosis. Go easy if you’re not sure how you’ll react.


Let’s take a moment and summarize the effects of a ketogenic diet on body weight, fat loss, performance, strength, and hypertrophy. What’s the verdict?

  • Keto works fine if you want to lose body weight and body fat. Calories in vs. calories out is still the boss, but a ketogenic provides some advantages when it comes to appetite. This could make it easier eat less without having to count calories. A ketogenic diet might also increase the number of calories you burn a bit, but probably not enough to have any meaningful impact on your body weight.
  • Current research suggests that a ketogenic diet won’t impair performance during low to moderate intensity endurance training. You can even improve your aerobic ability without carbohydrates. High-intensity training is where you might run into trouble. When exercising at a high intensity, fat and ketone bodies might not be good enough, possibly limiting your performance somewhat.
  • What about strength training and other anaerobic forms of exercise? No real long-term studies support keto here, but at least in the short term, you probably won’t have to worry about performing worse than usual. You can both maintain and improve muscular strength and power with a ketogenic diet, both as an average gym member and as a high-level weight lifter or powerlifter.
  • The one thing that might suffer is muscle growth. A number of the available studies show that going keto could limit your gains. It could simply be that a ketogenic diet makes you eat less, leading to less muscle growth than with a high-carb diet. In either case, that’s something to keep in mind. You can still build muscle without carbs, but maybe not as easily as with them.
  • Finally, is the ketogenic diet safe? We don’t need carbs to live and function. They can certainly be useful, but we have other systems in place if we eliminate them for some reason. When you cut out carbohydrates, you shouldn’t expect to feel tip-top. Nausea, dizziness, fatigue, and other unpleasant things are common the first days to weeks. Fortunately, these side effects pass when your brain and your body learn to use ketones properly. There are no long-term studies that guarantee the safety of the ketogenic study, but neither is there anything in particular indicating any dangers. As long as you choose healthy foods that cover your micronutrient requirements, you don’t have to put a time limit on your diet.

In Conclusion

A ketogenic diet is a viable alternative to traditional high-carbohydrate diets for active individuals and strength athletes. If you want to experiment with a more or less carb-free diet, there are few reasons to discourage you from doing so, although you might struggle a bit to gain as much muscle.

That’s it! You’ve reached the end of our guide to the ketogenic diet!

For everything about building muscle, check out our comprehensive article:

How to Build Muscle: Exercises, Programs & Diet

And if you’re looking for strength training programs, we’ve got you covered! All of them are suitable for the keto lifestyle.

Strength Training Programs & Workouts


  1. Int J Environ Res Public Health. 2014 Feb 19;11(2):2092-107. Ketogenic diet for obesity: friend or foe?
  2. Int J Environ Res Public Health. 2014 Feb 19;11(2):2092-107. Ketogenic diet for obesity: friend or foe?
  3. Epilepsia. 2008 Nov;49 Suppl 8:3-5. History of the ketogenic diet.
  4. JAMA. 1973 Jun 4;224(10):1415-9. A critique of low-carbohydrate ketogenic weight reduction regimens. A review of Dr. Atkins’ diet revolution.
  5. JAMA. 2005 Jan 5;293(1):43-53. Comparison of the Atkins, Ornish, Weight Watchers, and Zone diets for weight loss and heart disease risk reduction: a randomized trial.
  6. Diabetologia. January 2005, Volume 48, Issue 1, pp 8–16. Comparison of high-fat and high-protein diets with a high-carbohydrate diet in insulin-resistant obese women.
  7. Br J Nutr. 2013 Oct;110(7):1178-87. Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials.
  8. J Clin Endocrinol Metab. 2010 Feb;95(2):879-86. Role of fat hydrolysis in regulating glucagon-like Peptide-1 secretion.
  9. J Clin Endocrinol Metab. 2007 Oct;92(10):4052-5. Effect of macronutrient composition on postprandial peptide YY levels.
  10. J Physiol. 2009 Jan 1; 587(Pt 1): 19–25. The role of peptide YY in appetite regulation and obesity.
  11. Diabetes 2006 Dec; 55(Supplement 2): S70-S77. Glucagon-Like Peptide 1 Secretion by the L-Cell.
  12. Am J Clin Nutr. 2006 May;83(5):1055-61. Ketogenic low-carbohydrate diets have no metabolic advantage over nonketogenic low-carbohydrate diets.
  13. Am J Clin Nutr. 2016 Aug;104(2):324-33. Energy expenditure and body composition changes after an isocaloric ketogenic diet in overweight and obese men.
  14. J Clin Lipidol. 2019 Sep 13. Review of current evidence and clinical recommendations on the effects of low-carbohydrate and very-low-carbohydrate (including ketogenic) diets for the management of body weight and other cardiometabolic risk factors: A scientific statement from the National Lipid Association Nutrition and Lifestyle Task Force.
  15. Metabolism. 2016 Mar;65(3):100-10. Metabolic characteristics of keto-adapted ultra-endurance runners.
  16. Metabolism. 2018 Apr;81:25-34. Keto-adaptation enhances exercise performance and body composition responses to training in endurance athletes.
  17. J Sports Sci Med. 2018 Jun; 17(2): 259–268. Effects of a 4-Week Very Low-Carbohydrate Diet on High-Intensity Interval Training Responses.
  18. Int J Exerc Sci. 2019; 12(2): 786–799. Effects of a 3-week High-Fat-Low-Carbohydrate Diet on Lipid and Glucose Profiles in Experienced, Middle-age Male Runners.
  19. Med Sci Sports Exerc. 2019 Oct;51(10):2135-2146. Effect of a Ketogenic Diet on Submaximal Exercise Capacity and Efficiency in Runners.
  20. Ketogenic diet benefits body composition and well-being but not performance in a pilot case study of New Zealand endurance athletes.
  21. Metabolism. 2016 Mar;65(3):100-10. Metabolic characteristics of keto-adapted ultra-endurance runners.
  22. Med Sci Sports Exerc. 2019 Oct;51(10):2135-2146. Effect of a Ketogenic Diet on Submaximal Exercise Capacity and Efficiency in Runners.
  23. Advances in Nutrition, Volume 12, Issue 1, January 2021, Pages 223–233. High-Fat Ketogenic Diets and Physical Performance: A Systematic Review.
  24. Sports (Basel). 2018 Mar; 6(1): 1. The Three-Month Effects of a Ketogenic Diet on Body Composition, Blood Parameters, and Performance Metrics in CrossFit Trainees: A Pilot Study.
  25. International Journal of Sports and Exercise Medicine, 2017/04/30. A Low-Carbohydrate Ketogenic Diet Combined with 6-Weeks of Crossfit Training Improves Body Composition and Performance.
  26. J Strength Cond Res. 2017 Apr 7. The Effects of Ketogenic Dieting on Body Composition, Strength, Power, and Hormonal Profiles in Resistance Training Males.
  27. J Strength Cond Res. 2018 Dec;32(12):3373-3382. A Low-Carbohydrate Ketogenic Diet Reduces Body Mass Without Compromising Performance in Powerlifting and Olympic Weightlifting Athletes.
  28. Journal of the International Society of Sports Nutrition 9, Article number: 34 (2012). Ketogenic diet does not affect strength performance in elite artistic gymnasts.
  29. J Hum Kinet. 2019 Aug; 68: 233–247. Ketogenic Diet and Skeletal Muscle Hypertrophy: A Frenemy Relationship?
  30. Journal of the International Society of Sports Nutrition volume 15, Article number: 31 (2018). Efficacy of ketogenic diet on body composition during resistance training in trained men: a randomized controlled trial.
  31. Journal of the International Society of Sports Nutrition volume 17, Article number: 19 (2020). Effects of a ketogenic diet on body composition and strength in trained women.
  32. Nutrients 2021, 13(2), 374; Effects of Two Months of Very Low Carbohydrate Ketogenic Diet on Body Composition, Muscle Strength, Muscle Area, and Blood Parameters in Competitive Natural Body Builders.
  33. Journal of Strength and Conditioning Research: December 2020 – Volume 34 – Issue 12 – p 3463-3474. Effects of Ketogenic Dieting on Body Composition, Strength, Power, and Hormonal Profiles in Resistance Training Men.
  34. Ann Nutr Metab 2010;57:59–67. Metabolic and Appetite Hormone Responses of Hyperinsulinemic Normoglycemic Males to Meals with Varied Macronutrient Compositions.
  35. J Clin Endocrinol Metab. 2000 May;85(5):1963-7. The effects of carbohydrate variation in isocaloric diets on glycogenolysis and gluconeogenesis in healthy men.
  36. Diabetes Educ. 1997 Nov-Dec;23(6):643-6, 648, 650-1. Protein: metabolism and effect on blood glucose levels.
  37. Br J Sports Med. 2018 Mar; 52(6): 376–384. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults.
  38. Nat Rev Neurosci. 2018 Feb;19(2):63-80. Intermittent metabolic switching, neuroplasticity and brain health.
  39. Exp Clin Cardiol. 2004 Fall;9(3):200-5. Long-term effects of a ketogenic diet in obese patients.
  40. Ketogenic Diet, Treasure Island (FL): StatPearls Publishing; 2019 Jan-
  41. International Journal of Strength and Conditioning, 1(1), 2021-08-16. Resistance Training Recommendations to Maximize Muscle Hypertrophy in an Athletic Population: Position Stand of the IUSCA.
  42. Advances in Nutrition, 25 September 2019. Dairy Foods and Dairy Fats: New Perspectives on Pathways Implicated in Cardiometabolic Health.
  43. Diet, Nutrition, Physical Activity and Cancer: a Global Perspective
  44. Obesity (Silver Spring). 2018 Feb;26(2):269-273. A Ketone Ester Drink Lowers Human Ghrelin and Appetite.
  45. Cell Metab. 2016 Aug 9;24(2):256-68. Nutritional Ketosis Alters Fuel Preference and Thereby Endurance Performance in Athletes.
  46. Biomed J. Jan-Feb 2013;36(1):9-15. Medium-chain triglyceride ketogenic diet, an effective treatment for drug-resistant epilepsy and a comparison with other ketogenic diets.
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Andreas Abelsson

Andreas has over 30 years of training experience and is a highly appreciated writer and educator on exercise, fitness, and nutrition. Few people stay more up to date and have a better grasp of the field of exercise science than Andreas.