How Too Much Protein is Bad for Ketosis

The keto diet is known for being a very low carb, high-fat diet.

This approach helps you boost your ketone levels and enter nutritional ketosis, which is a metabolic state in which you burn mainly fat (ketones) for energy instead of glucose.

This is the defining difference between the ketogenic diet and Atkins or other low carb diets, which simply reduce some carbs and don’t try to put you in ketosis.

But there’s one more nutrient to consider and many misunderstand its role on the keto diet.

I’m talking about protein.

On keto, you will consume adequate amounts of protein — never less than you need. This macro is one of the hardest to nail down when starting keto due to all the conflicting misinformation about it.

Protein is a building block of life and a necessary component of any diet. It’s crucial for:

  • Healthy brain function
  • Skin, bone, and muscle health
  • Building muscle mass
  • Recovering after workouts
  • Cutting body fat

These benefits promote longevity, prevent injuries and boost your metabolism.

Unfortunately, a lot of ketogenic dieters are worried that eating too much protein might kick them out of ketosis.

Many low carb, high fat advocates believe excess protein can turn into sugar in your bloodstream through a process called gluconeogenesis and knock down your ketone levels. But as you’ll find out, this is only a myth.

In this article, we’ll talk about:

Can Too Much Protein Be Bad for Ketosis?

Eating too much protein is one of the biggest concerns for people who are just starting the ketogenic diet.

After all, ketones are produced from fat, so you should keep carbs and protein down to a minimum, right? Not necessarily!

Carbs are the only macronutrient that can seriously interfere with ketosis, which is why it’s important to watch out for hidden carbs and find the carb limit that works for you.

On the other hand, eating protein won’t affect your ketone levels. You can eat high fat and high protein (preferably fatty cuts of grass fed meat) and stay in ketosis.

That’s why many people who transition from keto to the carnivore diet have no problem staying in nutritional ketosis.

But what about gluconeogenesis (GNG)?

GNG is a real and necessary process that is already happening in your body. It’s not the enemy of ketosis, in fact, it makes ketosis possible in the first place.

Surprised? Here’s how it really works:

The High-Protein Myth: Do Not Fear Gluconeogenesis

There is a widely-circulated claim that excess protein is detrimental to ketosis because it causes gluconeogenesis.

This myth has since been disproven. However, there are plenty of articles published online stating this false claim, so Perfect Keto would like to explain how GNG really works on ketosis.

Gluconeogenesis (GNG) is a metabolic pathway that allows your liver and kidneys to make glucose from non-carbohydrate sources.

The word gluconeogenesis has three parts to it:

  • Gluco — coming from the greek root glukos – literally meaning “sweet wine.”
  • Neo — “new”
  • Genesis — “creation”

So a great way to think about it is this is how your body creates new sweet wine for your body. This process is special because it’s the creation of glucose from anything but carbs.

Your body takes compounds like lactate, amino acids (protein), and glycerol to manufacture glucose when there are no carbs around.

This may seem like a problem when you’re trying to run on ketones instead of glucose,  but the truth is gluconeogenesis has an incredibly important purpose — and no, it doesn’t harm ketosis.

Some people tout that “you don’t need carbohydrates to survive,” which is only partially true.

To clarify, you don’t need to eat any high carb foods to survive, but make no mistake — your body needs glucose and glycogen to keep you healthy (even on ketosis) and it will get this via survival mechanisms like gluconeogenesis.

3 Reasons Gluconeogenesis Is Vital

On a keto diet, your body uses gluconeogenesis for 3 main purposes:

  • Preventing hypoglycemia.Your glucose levels can never drop to zero, even on ketosis. GNG keeps your blood sugar on a healthy range so it doesn’t fall to dangerous levels (aka hypoglycemia).
  • Fueling tissues that can’t use ketones. There are a handful of cells in your body that can only use glucose to survive, including red blood cells, kidney medulla (inner part of the kidney), testicles and some parts of your brain. Ketones can cover up to 70% of your brain’s energy needs while glucose from GNG covers the rest. The other organs can’t metabolize ketones at all, so gluconeogenesis provides them with enough glucose to remain healthy.
  • Resupplying glycogen stores. You can actually replenish muscle glycogen through the GNG that happens during ketosis — at least if you’re not a professional athlete or participate in competitions. Glycogen is crucial for muscle recovery after workouts.

These functions are incredibly important. If GNG didn’t make enough glucose to cover them, your body could never make the switch to using ketones for energy because some cells (like red blood cells) would die and your blood sugar would drop too low.

This means gluconeogenesis makes ketosis possible.

Can Excess Protein Increase the Glucose Coming From GNG?

Now, could you boost the rate GNG if you eat too much protein? Not likely.

GNG is an extremely stable process. It’s not easy to increase it even with extra protein.

Gluconeogenesis (making glucose from non-carbs) doesn’t work at the same rate as carbohydrate metabolism (making glucose from carbs).

When you eat chocolate cake, your blood glucose quickly spikes in response to that sugar.

When you eat extra protein, your blood glucose doesn’t spike the same way. Studies have shown that GNG production doesn’t increase even with extra amino acids[*].

By now we have made a few things clear:

  • Gluconeogenesis is the process of making internal glucose from non-carb sources, including protein
  • Gluconeogenesis is necessary for survival
  • Gluconeogenesis makes ketosis possible
  • Eating too much protein won’t increase the rate of gluconeogenesis

But eating protein isn’t just safe, it’s necessary.

3 Reasons Why You Should Eat More Protein On Keto

Here’s why eating adequate amounts of protein is beneficial on the ketogenic diet:

#1: Protein Helps With Fat Loss

Most people on keto will limit their protein to 30-40 grams, limit their carbs to 10-20 grams, then eat an excessive amount of fat. This is a common mistake.

If your goal is to lose fat, increased protein consumption is a great way to approach your ketogenic diet plan. Here’s why[*][*]:

  • Protein is more satiating than fat
  • Protein is more nutrient dense
  • People tend to overeat when protein is low

Additionally, the most effective way to start losing weight on keto is to burn your stored body fat for energy, not the new dietary fat you’re eating.

If you eat too much fat, your body will burn that new fat coming in and won’t get the chance to burn your stored fat reserves.

You can overcome weight loss plateaus by increasing protein and lowering your fat consumption.

#2: Protein Provides Fewer Calories Than Fat

Your body needs to use more energy (calories) to burn protein than to burn to fat.

For example, when you eat a 100-calorie serving of grass fed beef, your body can only store 75% of it as calories because it requires 25% of calories to burn it and use it as fuel. Conversely, when you consume fat, you are storing up to 98% of it as calories[*].

This means you’re storing almost all of the calories from fat, whereas you’ll store less from protein since you use up some of the calories to burn it.

#3: Protein Deficiency Is Dangerous

Not eating enough protein on keto has serious side effects, including:

  • Worsened workout performance: Without enough protein, you won’t be able to maintain muscle mass, let alone build muscle.
  • Neuron atrophy: Your brain needs amino acids to function optimally. Research finds a protein-deficient diet can lead to atrophy and neuron loss[*].
  • Weaker immune system: A deficiency in the amino acid arginine can contribute to the dysfunction of your T cells — the cells that regulate your immunity.
  • Increased risk of diseases: A deficiency in amino acids can increase the risk of developing certain diseases, including: sickle cell disease, acute asthma, cystic fibrosis, pulmonary hypertension, cardiovascular disease and certain cancers[*].

In fact, a lot of these keto side effects happen due to eating too little protein[*][*]:

Now that you know why protein matters, it’s important to choose the best possible protein sources for your diet.

Choosing the Best Keto Protein Sources

When selecting keto protein sources, choose the highest quality you can reasonably afford.

When grocery shopping, be sure to refer to the Keto Diet Food List and the Ketogenic Diet Grocery List for ideas. If you are an athlete who typically uses protein powder, choose a keto-friendly brand (discussed below).

Keto-Friendly Protein Sources

These are the best sources of protein on the keto diet:

  • Beef, preferably fattier cuts like steak, veal, roast, ground beef and stews
  • Poultry, including chicken breasts, quail, duck, turkey and wild game — try to focus on the darker, fattier meats
  • Pork, including pork loin, tenderloin, chops, ham, bacon and ground
  • Fish, including mackerel, tuna, salmon, trout, halibut, cod, catfish and mahi-mahi
  • Shellfish, including oysters, clams, crab, mussels and lobster
  • Organ meats, including heart, liver, tongue, kidney and offal
  • Eggs, including deviled, fried, scrambled and boiled — use the whole egg
  • Lamb meat
  • Goat meat
  • Grass fed, full-fat dairy, including grass fed butter, heavy cream, cottage cheese and cream cheese
  • Vegetarian sources, like macadamia nuts, almonds and nut butter

The Best Keto Friendly Protein Supplement: Collagen

Collagen is a type of protein — the most abundant protein found in your body.

It’s considered the glue that holds your body together, making up the tissue in cartilage, muscles, joints, skin, hair, eyes, heart, gut, brain, and nails, and it’s credited with a wide range of health benefits, including:

  • Better skin health
  • Hair loss prevention
  • Muscle growth and regeneration
  • Maintaining the integrity of tendons, ligaments and cartilage
  • Strengthening your bones and preventing osteoporosis
  • Repairing tissues (forming scars)
  • Maintaining proper vision
  • Preventing leaky gut
  • Helping your heart beat
  • Ensuring optimal brain function

Perfect Keto Collagen Protein Powder is the first keto protein powder made with 10 grams of collagen peptides. Perfect for a post-workout protein shake, this supplement protects your hair, skin and nails while providing easy-to-digest protein.

For more on collagen:

How Much Protein Should You Consume on Keto?

The Standard American Diet (SAD) is heavy in carbs, with some protein and very little fat. On keto, you take a seemingly opposite approach, with the bulk of your calories coming from fat, some calories coming from protein and very few from carbohydrates.

While every person has individual needs, most people follow these macronutrient guidelines to enter (or stay in) ketosis:

  • 75-80% of calories should come from fat
  • 20% of calories should come from protein
  • 5% of calories should come from carbohydrates

This is a common way to break down your macros on the ketogenic diet. And while it may help you to start producing ketones, it may not be the most effective approach for overall body composition and weight loss.

Instead of setting up macronutrient percentages, here’s a better alternative:

Step #1: Protein Always Comes First

The first step for successfully tracking your ketogenic diet macros is to calculate your protein intake.

The amount will differ depending on the activity level per individual.

If you’re sedentary, consume 0.8 grams of protein per pound of lean body mass at a minimum.

Lean body mass is the amount of weight you carry that isn’t fat. Use a bioelectrical impedance scale, calipers or get a DEXA scan to find your lean body mass. Then take that weight and multiply it by 0.8. This is the amount of protein you should eat every day.

If you’re an athlete or looking to build muscle, consume 1-1.2 grams of protein per pound of bodyweight.

Note: This is the absolute minimum you should be eating. You can eat more if needed and you shouldn’t worry about creating excess glucose. It’s more problematic to get less protein than it is to eat more.

Step #2: Calculate Carbohydrates

Reduce your carbohydrate intake to 20-50 grams of total carbohydrates.

Athletes and those looking to build muscle can consume higher amounts whereas people who live a sedentary lifestyle should try to stay under 30 grams of total carbohydrates.

Step #3: Fill in the Rest of Your Calories From Fat

Once you have calculated your protein and carbohydrate intake, subtract that amount from your daily total calories.

Those remaining calories should come from healthy fats.

To find the amount of calories per macronutrient:

  • Protein = 4 calories per gram
  • Carbohydrates = 4 calories per gram
  • Fats = 9 calories per gram

Here’s an example:

Let’s assume your goal is to eat 150 grams of protein per day and 30 grams of carbohydrates with a 2,100 daily calorie allowance.

  • 150g protein x 4 = 600 calories
  • 30g carbohydrates x 4 = 120 calories
  • 2,100 – (600 + 120) = 1,280 calories
  • To find your fat intake = 1,280 / 9 = 142g of fat

The macronutrient breakdown for this example comes out to:

  • 150 grams protein
  • 142 grams fat
  • 30 grams carbohydrates

If you’re not seeing the results you want with the ketogenic diet, using this approach may help you overcome any ketogenic obstacles you’re experiencing.

Use the Perfect Keto Macro Calculator to find your ideal macro breakdown.

What to Measure: Results Not Ketones

If your goal is to maintain optimal energy levels and achieve a lean physique, you should not worry about constantly tracking your ketone levels.

Instead, focus on long-term lean tissue growth.

Ketone production is not the only metric to track when gauging your success on the ketogenic diet.

Looking at the mirror, measuring your lean body mass and assessing your energy levels are much better ways to determine the effectiveness of your diet. Why?

Because producing ketones doesn’t always mean you’re burning them for energy.

When you first start the ketogenic diet, your body may be excreting excess ketones through your breath and urine. Often times, these ketones aren’t being used for energy because your mitochondria haven’t adapted to processing ketones effectively.

The longer you follow the ketogenic diet, the more efficient your body becomes at using ketones as its main fuel source.

This is why many people who are keto-adapted will have slightly lower ketone levels (.6 – .8 mmol). Their body isn’t flushing out excess ketones — it’s using them.

Building lean mass overtime is a better indicator of an effective ketogenic diet protocol because it proves that you’re burning off your body’s fat storages for energy.

Bottom Line: Unless you are following the ketogenic diet to help with serious health conditions like cancer or Alzheimer’s disease, maintaining high ketone levels should not be a priority for you. Instead, track your overall body composition, lean tissue growth and energy levels.

Stop Undereating Protein

Many people in the ketogenic community have been misguided into keeping protein intake relatively low to prevent glucose production through GNG.

Because of this, keto beginners may never see the lasting results they’ve been promised on the low carb, high fat lifestyle.

The truth is protein is just as important as healthy fats on the ketogenic diet.

If you have hit a weight loss plateau, experienced a dip in energy or noticed hormonal imbalances, increasing your protein intake can drastically help.

Instead of focusing on ketogenic macronutrient percentages, follow the steps above or use the macro calculator to figure out your new macro intake and make your keto diet work even better for you.

Dr. Anthony Gustin is a board-certified sports chiropractor, functional medicine practitioner, entrepreneur, podcast host, and founder of Perfect Keto.

Over the last few years, he has treated thousands of patients with movement rehab, internal diagnostics, and natural interventions, including NFL, MLB and NBA champions. After growing his sports rehab and functional medicine clinics to six locations in San Francisco, he shifted his mission to help as many people as possible achieve optimal health and well-being.

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Responses (47)

  1. Is there an author for this page? I would like to use this information in a paper I’m writing and having an author would make it easier to cite properly.

  2. Great line up. We’ll be linking to this great article on our website.

    Keep up the great writing.

  3. Is the glucose meter the same as what diabetics use to test? If so what values are you looking for? If not do you have a meter you recommend? We think we have been in ketosis for over a week (next to the darkest color on the strip and eating about 16 carbs a day on average with about 75-80%fat) and we aren’t seeing anything other than a little water weight .. no BMI change. Any suggestions?

  4. Way cool, some valid points! I appreciate you making this post
    available, the remainder of the site is also high quality.
    Have a enjoyable.

  5. I have a problem measuring protein from meat : say I cook with 250g frozen meat. Result : say 160g cooked meat, with the juice and fat in the pan. How much do I record : the frozen meat ? the cooked meat ? with or without the juice and/or the fat ? I can’t find the answer anywhere and it makes a world of difference. Can you help ? Thanks !

  6. I think this is one of the most significant info for me.

    And i am satisfied studying your article. But wanna statement on few normal issues,
    The website style is ideal, the articles is truly excellent :
    D. Good activity, cheers
    It could be hard to squeeze a fat-blasting workout into your daily program, but it’s nonetheless feasible to crank up your
    calorie-burning potential all day long. The message that is
    straightforward will be to eat a diet that is healthful also
    to engage in more reasonable-to-strenuous physical action.

  7. Greetings! Very helpful advice on this post! It is
    the little changes that make the biggest
    changes. Thanks a lot for sharing!

  8. I haven’t been eating Keto very long but I have the strips and I’m stay in Ketosis most of the time. Have a question. I’m getting to where I’m not very hungry in the afternoon which is new for me!! BUT do I need to eat something to keep me in Ketosis or wait till dinner time kind of thing. Also if I eat less Bc I’m not as hungry at dinner will that throw me off also?… thanks

  9. It’s actually a great and helpful piece of information. I am satisfied that you simply shared this helpful information with us.

    Please stay us informed like this. Thank you for sharing.

  10. 75, 20, 5 is an ideal ratio but is there a higher protein, lower fat percentage you can have and still be in ketosis? Some days I find it hard to eat that much fat.

  11. “However, there’s another way the body can create carbohydrate-style energy in the body—by breaking down amino acids from the protein in your muscles. Gluconeogenesis (GNG) is how your body turns protein into glycogen that can be used as glucose to burn for fuel.”

    I agree that it would prevent the body from entering ketosis, but I don’t understand why the body has to eat the protein from muscle and not from the proteic foods you eat.

  12. I think there is some misconceptions in this article. Gluconeogenesis is NOT bad for keto, it is actually the mechanism by which non-carbohydrate sources turn into energy (be it protein or fat). You need gluconeogenesis to create ketones, after all.

  13. If you’re arguing that you always need a little bit of glucose and insulin, that is correct. However most of the response people will have is that it drives up insulin too much. Ketones are produced via beta oxidation from fat.

  14. The problem with the MyFitnessPal app is that you must pay a monthly fee in order to receive the full benefit of the app. Some of us can’t afford regardless if it’s a small amount or not.

  15. In this article you stated
    “Calculate your calories on the site, then enter the nutrient percentages above (60% fat, 35% protein, 5% fat) to calculate your gram totals per nutrient group. Use this as your starting point for the amount of daily..”

    Did you mean 5% carbs?

  16. You guys gotta thinking of joint venture with Atkins. They have love you and your great for them.

  17. I have tried the MyFitnessPal app but looking up the food is just a guessing game. There are so many people putting their own food entries in that you don’t know which is accurate and which ones are just being guessed at. I think they should never have allowed everyone to put entries in. It was so confusing that I had to stop using it. Any other options?

  18. Great to hear! If you are in ketosis your body will have the metabolic flexibility to use the food you eat and/or your own body fat. So you don’t have to eat if you aren’t hungry, your body has about 40K calories of fat in storage ready for action! 🙂

  19. If im fasting and in ketosis, will eating the same amount of protein as usual throw me out of ketosis? Will the body just utilize the protein for muscle repair or will it turn it into glucose?

  20. Hey Luke, it really just depends on how your body reacts to different amounts of protein – it’s very individualized. I would recommend testing your blood ketones to really find out!

  21. Use the “MyPlate” app. You set your micros for free! You can either barcode scanner your food or manually enter it in. Super easy!!

  22. Hi

    As per the lean mass calculation my protein macros are around 65. But if I calculate as per percentage then 35% protein and cal intake being around 1200 my protein is higher. Around 105. So which macro do I follow ?

    I did 1 round of keto in April for 2 months with protein between 60-70 and fat around 80 and carbs below 20. Lost 7 kg. Was doing some cardio then
    Have started lifting weights thrice a week now and increased protein to 100 with rest being same … I am not loosing at all. So I am really confused which macros to follow. If I go back to my round 1 macros then will I be able to lift heavy ?

  23. Hi Pooja, the macros from round 1 sound like they were spot on and it seems like you had great success with those numbers. I would try that out again for a few weeks and see what happens. You’re body may need a few days to adjust back again and it could hinder your lifts in the beginning but then you should be right back to lifting heavy in no time. Ketones are muscle sparing and you don’t need as much protein as you may think to lift heavy and gain muscle!

  24. So, my morning consists of a scoop of vanilla exogenous ketones in some coconut milk, then I will have a coffee with heavy whipping cream and the perfect keto mct powder. I hold off on lunch until noon. I use urine testing strips to see if I’m in ketosis and it comes up as barely being in it on the lighter side of the spectrum. I eat protein and fat with little carbs, only coming from veggies. Is there a reason I’m not seeing a darker color on my strip? I’m starting to think it isn’t working at all to get me into ketosis. Any insight would be appreciated!

  25. Hey Katie, the urine strips are useful to see if you are producing ketones but I would not get too caught up on the color (how dark or light it is). If you’re feeling great and seeing results – keep doing what you’re doing! Also, once you are keto for a while, the urine strips may not be as accurate because they measure the amount of ketones you are “dumping” – so if you become more efficient at using those ketones for fuel (which you will the longer you’re keto) than you won’t excrete as much in your urine…make sense?

  26. Absolutely! It’s called modified keto…check it out. Moderate protein, medium day. Eating 20g carbs or under daily will guarantee ketosis within several days.

  27. Thank you for the information, AND the questions! I am new! Have been on keto since December 4. I have 70/25/5. It has been challenging for me to get the macros in the right place. I have had trouble with the fat portion and read about fat balls. Any comments on those? It is amazing to me to think that 17 days ago I was over 300 lbs. Now I am at 285. Today, I was way over in the carbs, 43g! Oh man, I feel so bad about it! This is how I came across your page. Protein has been higher than recommended. So, thank you for your page, and the questions. I don’t miss sugar, or that 20 lbs! But I do want things to keep moving.

  28. Is gluconeogenesis demand-driven or supply-driven? The idea of too much protein causing increased gluconeogenesis only makes sense if it is supply driven. But the consensus seems to be that gluconeogenesis is demand-driven–the body can turn protein into glucose >if< it needs to. Otherwise, body builders and powerlifters, who consume protein in quantities that would be absurd if the protein just turned into glucose, would be unable to turn that protein supply into muscle. Do you have references to the contrary?

  29. You should be using a protein target in grams, not a ratio. To find your protein target, use this https://ketogains.com/ketogains-calculator/

    And fat is not a target. It’s meant to be filler, so you don’t eat carbs. Hit the protein target, keep carbs under 25g, and eat ONLY as much fat as you NEED to, to feel fine.

  30. Hello! Just came across this blog. This is my second attempt at keto. I have the urine strips to test for now. What if I’m at roughly a 73, 25, and 3 ratio? Am I hurting myself greatly by the elevated protein and not enough of the others? I use the myketo app. I try to measure using the published nutrition values on the protein I eat.

  31. Is anyone else having a problem finding true Keto recipes. So far researching the internet I have found atkins recipes relabled as keto. They are just recipes that are enormously high in protein. They usually are close to zero carbs but they also have very little fat in them. Where can I find real keto recipes that actually have more fat than protein?

  32. I can say from current lifestyle choices. I do a high protein, moderate fat, low carb Keto and I have no problem being in ketosis.

    Last night I had a cheat meal. Cheese burger with half the bun, and a small soda. I’m still in ketosis today.

    A couple other individuals I know prefer the high protein vs high fat keto.

    This past week which was actually the 2nd time I’ve been on this diet. My body fat percentage is high as well. Day 1 I weighed in at 181.8lbs this morning, day 7, I weighed in at 175.6 I’m 5’2

    The last go around I lost about 20lbs in the first month.

    I feel energized and awake. Actually alert and not all sluggish. My portion sizes are going back to what they should be.

    My diet is healthy and it incorporates mostly lean meat and fish. Veggies, nuts, and fruits. My net carbs still always fall in 25-30g a day. Protein is about 120g fat is about 90g. 1200 cal diet.

    I personally feel that everyone’s body chemistry is different and they break down said food differently.

  33. I am in adrenal fatigue again. Will this work for adrenal fatigue or what would I have to watch out for?

  34. For adrenal fatigue, use apogenic herbs. ashwaganda is good. Rhodiola, or maca root. All really good. Of course you want organic. Make sure you check that they have not put fillers in them. Do your research. Be good to your body. It is the only one you have.

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