How much protein can you eat in ketosis?
In the last post, Why You’re Not in Ketosis, I revealed why, and how I fixed it (by reducing my carb and protein intake to 20 and 60 grams per day respectively).
But, I had a problem. Though it felt awesome to be back in ketosis, it sucked to eat so little protein – 60 grams a day isn’t much for a meat lover like me.
Could I eat more protein AND remain in optimal ketosis?
I was going to find out.
The protein experiment
I designed the following experiment:
First, I would increase my protein intake from 60 grams a day to the level where I would no longer be in optimal ketosis.
Then, I would reduce my protein intake until I was back in optimal ketosis, using what I ate on the last day to define my daily-protein limit.
Finally, I’d eat to this daily-protein limit every day for a week to test its accuracy, adjusting my protein intake if necessary.
To increase the trustworthiness of the experiment, I added five rules:
1. Keep eating 10-20 grams of carbs a day
2. Keep eating during a four-hour window (5-9pm)
3. Adjust my protein intake gradually
4. Make no other major changes to my life
5. Measure my blood-ketone levels every morning before eating
“Nice plan”, I thought.
But there was one thing I hadn’t taken into account…
Preparation
To start off the experiment, I measured my blood-ketone levels: 2.0 mmol/L.
Not exactly shocking news – I had been eating 45-60 grams of protein and 10-20 grams of carbs a day for weeks, being in optimal ketosis almost every morning.
But all that could end soon – it was protein time.
Day 1: Taco-cheese shells
On the first day of the experiment, I ate similarly to how I’d eaten lately – butter, eggs, ground beef, and some vegetables, but no berries or nuts. For the extra protein, I ate the totally delicious taco-cheese shells. Awesome.
The totals for the day were 85 grams of protein (40 grams more than the day before), 10 grams of carbs (10 grams less than the day before), and lots of fat.
Would I be out of optimal ketosis by tomorrow morning?
Day 2: Low-carb pizza
I woke up at 06:10 am. Feeling a little nervous, I walked quickly to the living room, sat down by the dinner table, and prepared my blood-ketone meter. “Not again”, I thought as the needle closed in on my finger.
After ten seconds, I saw this:
Oh yeah, optimal ketosis and 0.4 mmol/L more ketones than yesterday! Good news, but it was early days.
What caused the ketone increase? Perhaps it was eating 10 grams carbs less than the day before, perhaps it was random variance (the blood-ketone meter isn’t 100% accurate), or perhaps it was something else. I couldn’t be sure.
I upped my protein and carb intake a notch by eating a few more vegetables and raspberries, and by replacing those crispy taco-cheese shells with a few slices of the legendary low-carb pizza. So delicious!
The totals for the day were 100 grams of protein (+15 grams), 20 grams of carbs (+10 grams), and lots of fat.
Could my ketone levels survive this carb and protein onslaught?
Day 3: Liver, eggs, cheese, and more pizza!
I woke up early, walked quickly to the living room, sat down by the dinner table, and prepared my blood-ketone meter. “Ouch, not again”, I thought as the needle was about to attack my finger. I touched the ketone strip and waited.
After ten seconds, I saw this:
Oh yeah, optimal ketosis! 0.4 mmol/L less ketones than yesterday, but the same ketone levels as on day 1 having eaten 40 grams more protein. And I had doubled my carb intake from the day before.
What caused the ketone reduction? Perhaps it was eating more protein and/or carbs, perhaps it was random variance, or perhaps it was something else. I didn’t know.
I decided to go for it. How much protein could I possibly eat in a day while keeping carbs to maximum 20 grams?
I stuffed myself with liver, eggs, cheese, and more low-carb pizza. Eating so much felt great, but after a while I was totally stuffed. I went to bed feeling nauseous – too much food.
The totals for the day were 135 grams of protein (+35 grams), 20 grams of carbs (+0 grams), and lots of fat.
Day 4: Bye, bye ketosis, right?
I woke up super thirsty. After chucking down a big glass of water, I walked to the living room, sat down by the dinner table, and prepared my blood-ketone meter. “Here we go again…”, I thought as the needle charged down on my finger. I touched the ketone strip, and waited.
Surely it was time to kiss ketosis bye, bye:
2.3 mmol/L, really?
After eating as much protein as I could stomach, my ketones went up by 0.3 mmol/L from the day before. Not what I expected.
Day 4 to day 10: Eating as much protein as I want
Could my daily-protein limit be higher than the amount of protein I wanted to eat? Or perhaps my body was in need of extra protein after a weeks of eating too little?
To find out I decided to change the experiment.
Instead of forcing myself to eat more and more protein, I would eat all the protein I wanted to for a week, and see whether that would kick me out of optimal ketosis. If so, I would reduce my protein intake until I was back in.
So, every day for a week, I ate in the 80-130 grams of protein, and 10-20 grams of carbs, range – plus lots of fat of course. What happened to my blood-ketone levels?
They stayed around 2,0 mmol/L every morning – optimal ketosis.
These days: Few surprises
I’m still eating as much protein as I want, but I’m super strict with my carb intake – I keep it to maximum 20 grams a day almost every day.
To make sure I don’t drop out of ketosis without knowing, I measure my blood-ketone levels once a week. So far there’s been only one surprise – 0.5 mmol/L ketones the morning after I ate at a Lebanese restaurant near the Diet Doctor main office – probably some added sugar.
What I’ve learned from these experiments
A while back I found out I’d been lying to myself for years – I wasn’t really in ketosis. To understand why, I did an experiment and learned that I’d been eating too many carbs and possibly too much protein.
I immediately reduced my carb and protein intake to maximum 20 and 60 grams per day respectively, and boom – straight back into optimal ketosis.
But I didn’t love eating just 60 grams of protein. To find out how much more I could eat AND remain in optimal ketosis, I did the above protein experiment.
From this latest experiment, I’ve learned that I can likely eat 80-130 grams of protein a day for weeks, and possibly for way longer, without dropping out of optimal ketosis.
So, for me, the key to optimal ketosis is to restrict the intake of carbs to less than 20 grams of carbs a day.
Now, let’s talk about you.
How much protein can you eat in ketosis?
First note that far from everyone has to stay in optimal ketosis (1.5 – 3 mmol/L). Lots of people do fine on low carb without it. But staying close to that ketosis range may improve mental and physical performance, it often results in more weight loss and it can have certain other potential health benefits, like controlling epilepsy or migraine.
Here’s what Diet Doctor has to say about reaching optimal ketosis:
Restrict protein to moderate levels. If possible stay between 1.2-1.7 gram of protein per day, per kg of body weight (about 0.6 grams per pound). So about 85-110 grams of protein per day if you weigh 70 kilos (154 pounds).
The most common mistake that stops people from reaching optimal ketosis is not too much protein. It is too many carbs.
As this post indicates, I can eat significantly more protein and remain in optimal ketosis. Can you?
That depends.
If you, like me, are a 36-year old insulin-sensitive male, who weigh 152 pounds, exercise for 10-15 minutes five times a week, and have no history of obesity or diabetes, then you can likely eat a great deal more protein.
However, if you’re overweight and/or have high blood-sugar levels, then you may want to stay in the lower end of the moderate range.
If you too want to eat more protein AND be in optimal ketosis, here are two things you can do:
A. Exercise more.
The more you exercise, the more protein your body needs – walking, running, and resistance training are all good options.
When you exercise more, you can increase your protein intake. To make sure you don’t go overboard with protein, measure your blood-ketone levels frequently and adjust your protein intake accordingly.
Remember to keep your carb intake to maximum 20 grams a day.
B. Find your daily-protein limit for ketosis
Perhaps your daily-protein limit for staying in optimal ketosis is different from what Diet Doctor generally recommends?
To find out, do this:
1. Buy a blood-ketone meter with test strips (Diet Doctor does not make any money from you buying this).
2. Eat less than 20 grams of carbs a day for a week. Then, test your ketones first thing in the morning before eating anything.
3a. If your blood-ketone levels are at 0.5 mmol/L or above, increase your protein intake gradually over the next week. Measure your blood-ketone levels every morning and see what happens.
How many grams of protein can you eat per day before your ketone levels drop below 0.5 mmol/L? Eat a little less protein than that.
Keep measuring your ketones for a few days, and if you’re always in ketosis, measure just once a week.
If you drop out of ketosis, make sure you’re eating maximum 20 grams of carbs a day. If you already are, but your ketone levels are not in the optimal range, reduce your protein intake a little.
3b. If your blood-ketone levels are below 0.5 mmol/L, reduce your protein intake gradually over the next week. Measure your blood-ketone levels every morning and see what happens.
How much do you have to reduce your protein intake before your ketone levels rise above 0.5 mmol/L? Eat a little less protein than that *.
Keep measuring your ketones for a few days, and if you’re always in optimal ketosis, measure just once a week.
If you drop out of ketosis, make sure you’re eating maximum 20 grams of carbs a day. If you already are, but your ketone levels are not in the optimal range, reduce your protein intake a little.
* We don’t recommend that you eat less than 0.4 grams of protein per pound of desired weight for long periods of time. You need protein.
Three follow-up questions
1. What would happen if I ate more than 135 grams of protein a day?
I don’t know.
I assume my blood-ketone levels would start dropping at the point when my body no longer needs all the protein it’s getting. At that point, it would likely convert the extra protein to glucose which would raise blood sugar and reduce blood-ketone levels.
I won’t test this anytime soon though as I don’t want to eat more protein than I’m doing now.
2. What would happen if I ate 80-135 grams of protein a day for months or years?
I don’t know.
I think doing so would keep me in optimal ketosis – that’s what the findings from this experiment indicate – but I won’t know the answer to this question for a while yet. I’ll keep measuring my ketones weekly and will give you an update later this year.
3. What would happen if I exercised less?
I don’t know.
I assume doing so could reduce my blood-ketone levels a little as my body would need less protein, but at what point that would happen I’m not sure.
Next
The above is the second of a 3-part blog series. Here’s the next one: What to eat in ketosis
More
A Ketogenic Diet for Beginners
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94 comments
Ive notice just how sensitive my body is to food intake and definitely notice reduced ketones after eating to much protein. Ive been in ketosis for 4 months approx and lost 20kg weight
BJARTE,
One Question, I notice that you eat all your meals in a 5 hr window, what exactly do you consume outside of that window ? - Coffee, alcohol perhaps, cream ..... ?
You should read what Jason Fung says about fasting versus starvation.
Also read up how ketoacidosis and nutritional ketosis are two completely separate things, the former a critical diagnosis where too little insulin combined with high fasting glucose triggers very high ketone levels, over 20. Needs medical care!
Nutritional ketosis is something quite different and someone who fights to stay in ketosis should know how easy it is to get out of ketosis.
During a 9 day water fast I reached maximum of my ketone meter, I believe it is 8, so my actual level could have been higher.
Pls remove the graph.
Outside the four-hour window I consume water, coffee with some cream, fish oil, and magnesium. Recently I've added salt too.
Do your research people. Not on blogs like DietDoctor, but actually look up studies. You'll find out that the only thing that triggers ketosis is the restriction of carbohydrates. The amounts of fat or protein you eat do not matter.
Obviously you don't want to eat three times your body weight in grams of protein, but really: who does that? Just make sure you provide your body no more than 20 to 50 grams of carbohydrates per day (it varies, some can go 30, some have to stay below 20, etc.) and you'll be in ketosis after a couple days.
Stop overcomplicating the ketogenic diet. It's not that hard.
Excess proteins are handled by the body to break down into some sugars, so I think it is entirely reasonable to do this experiment, whatever the critics above say. It is fascinating, however, that one can eat a great deal more protein than 1g per Kg and stay in ketosis, something I am rather relieved about as I eat enormous quantities of cheese and I struggle to find enough fat to eat!
He typically will make up a casserole type meal out of a fatty meat, he portions this 450g of meat in his lunchbox to this he adds 150g of lard microwaves it at meal time and stirs in the now melted lard and that is it!
Rarely eats vegetables, rarely has a multivitamin and is the picture of health.
I don't have any ketone data from him, not sure if he has ever monitored it.
I have recently been adding some lard to some of my meals maybe a couple of heaped tablespoons and certainly found that it helps tremendously in making me feel full and able to go much longer 'till I feel hungry... I do plan to try this in the future now I'm back from holidays and will get some more test strips to monitor ketones.
I am a Family Doctor who practices low carb. I have been trying to get around the optimal amount of protein for a while. This post helps to answer that question. Thank you.
I ended up in the ER a year ago the day after fasting with 3+ ketones and was diagnosed with "metobolic ketoacidosis". I had been eating low carb for about six-weeks, was at the low end of my weight range (115 for 5'5'') and had fasted for only 1 day. I had a glucose reading of 57 that morning and 60 later that evening even after eating. (I am not diabetic, but have a strong family history, so I check my glucose levels so I don't lie to myself about carbs. If I eat high carb, my glucose levels are running into the pre-diabetic range) I was eating about 75 grams of carbs prior to that fasting day so not extremely low carb, either. My blood PH was off. Abdominal pain, vomiting, diarrhea and the feeling like I was "coming apart" were what sent me to the ER. Was in the ER all night-lots of tests, etc.
They were baffled by my results - either a person who is starving or an alcoholic have these kinds of results.
I think I am a rare case, but it is important for people to understand their own bodies and to know that ketoacidosis is a real and serious issue. No one has been able to explain to me why I ended up with these issues after a 1 day fast.
Remember YOU are the variable.
ketosis IS impacted by Protein intake - check the Art and Science of Low Carbohydrate Living which is not a blog but written by two of the most respected researchers in the field of keto - Dr Jeff Volek and Dr Stephen Phinney.
Specifically they state:
Too little or too much protein can be problematic in the keto-adapted state. Aim for protein intake between 0.6 to 1.0 grams per pound of lean body mass.
Too much protein and your body converts amino acids into glucose which raises insulin levels. Raised insulin levels actually switches off fat burning - which means lower ketones.
So, I think it is fair to say that protein does have a role in ketosis......Just because it is not effecting you does not mean it does not have an effect.
Deb
I find it amazing that you are doing these kind of "experiments" on the diet "doctor". Are you really that ignorant about protein and gluconeogenesis? It's a fallacy that excess protein is metabolised into glucose.
Another example: lunch was ground meat, cheese (1 slice), 3 eggs, hot sauce (no sugar, just vinegar and peppers), anchovies, and sardines. My blood sugar rise? +15, taken about an hour after eating.
It typically takes me 80+ hours of fasting to get my ketones above 1.
And I have hundreds of blood tests to prove all of this.
For those of us who are insulin resistant, his results can't be applied to ours.
What surprises me is actually the fact that no matter what diet you are following you will still have certain amounts of ketones in your body/ flushed out of your body... so why is it called a ketogenic diet? I mean usage of in body "storages" - fat, muscles and liver (where there are glycogen stores) will produce ketone bodies anyway...
Very interesting experiment though :) Thank you for taking time to try it out and share the results :)
Maybe this article can be a help...
https://www.dietdoctor.com/low-carb/gain-weight
Yes!
I’m new to the diet and after 4 days, I read 0.7 so not in optimal ketosis. My question is, how can you possibly live on 60g of protein? Aren’t eggs protein? Cheese? Obviously meats? What on earth would you eat without these??? How are you defining protein as this means you would be eating less than a small tin of tuna per day the way I understand it. Thanks.
Im also new to the diet and can not get into ketosis. Im watching my carbs, Zero sugars BUT find it impossible to get enough fats without the aded protein. Where are people getting these no protein fats from if you are restriction the carbs?
I also found that with the experiment, it was a tiny amount of food.
Any advise would be greaty appreciated.
Lee-Anne
One egg contains approx. 8 gram of protein.
https://articles.mercola.com/sites/articles/archive/2014/09/03/too-mu...
https://www.mensjournal.com/food-drink/real-danger-too-much-protein/
//The Institute of Medicine recommends that adults get a minimum of .4g of protein for every pound of bodyweight per day (that’s about 65g for a 175-lb guy). But a study in Applied Physiology, Nutrition, and Metabolism found that that number should be more like .6g to build lean muscle mass. A high-protein diet takes it a notch further and loads you with 1-1.5g per pound of bodyweight.//
I’m eating 20carbs 50 protein. Calories 1300
Weight 90kg and need to lose 25kg
Age 68 and winning the fight during my first week - feel great on this diet
What did you end up adjusting? How much protein and fat were you eating before this?