How much protein you should eat on Keto for optimum results is widely contested...
Some believe that too much protein may be detrimental and could throw you out of ketosis.
Others argue that too little can hamper recovery, decrease lean muscle mass, and make it harder to lose weight.
In this article, we’ll take a deep dive into all things protein and Keto to help clear up any confusion.
Why is Protein Important?
Protein is an essential macronutrient, needed for a whole host of important bodily processes. These include:
- Creation of key enzymes and hormones [*]
- Muscle growth and repair [*]
- Supporting healthy bones and joints [*]
- Promoting healthy skin, hair, and nails [*][*][*]
- Maintaining pH of blood and bodily fluids [*]
- Supporting immune function [*]
People who don't get enough protein may run into various issues that are less than ideal: [*][*][*]
- Thyroid issues
- Decreased muscle mass
- Hormonal imbalances
- Fatty liver
- Increased cortisol
- Struggles with weight
Can I Eat Too Much Protein on a Keto Diet?
A widespread fear surrounding Keto is that consuming too much protein may lead to the upregulation of a process called gluconeogenesis (GNG) and throw you out of ketosis, undoing all your hard work.
The truth is, GNG is essential for our overall health, and actually allows us to remain in ketosis.
GNG may sound complicated, but it’s simply the metabolic process whereby your liver and kidneys make glucose from non-carb sources such as amino acids (the building blocks of protein). It’s completely natural and happens in Ketosis regardless of your protein intake. In fact, studies suggest that extra protein availability does not lead to an increase in GNG production [*].
Although we restrict dietary carbohydrate and glucose intake on a Keto diet, the truth is that the body still requires small amounts of glucose to support important bodily processes, including:
- Fueling tissues that can’t run on ketones [*,*]
- Preventing hypoglycemia (low blood sugar) [*]
- Converting lactate to replenish glycogen stores in active individuals [*]
GNG allows the above to continue on while the rest of your body is fueled up on clean-burning Ketones.
Bottom line: Your body needs some glucose to survive, but it doesn’t need to come from a high carbohydrate diet. Instead, maintaining adequate protein intake on Keto will give your body just enough glucose to fuel your body while still benefiting from running off ketones (fats) for everything else.
How Much Protein Should I Eat On a Ketogenic Diet?
As we touched on earlier, the side effects of consuming too little protein can be serious, so it’s important to ensure you're getting enough.
The macros of a typical Keto diet can be broken down as follows:
- Protein: 20-25%
- Fat: 65-80%
- Carbs: 3-10%
To get your personalized numbers, we recommend calculating your protein as a first priority. From there, keep carbs at a minimum and fill the rest with healthy fat sources.
If you don't feel like doing a bunch of math, there’s good news:
In the Carb Manager app, we have a handy calculator that determines your personal macro breakdown and how many grams of each to consume per day for your goals.
Just plug in your metrics and activity levels, and we do the rest!
Want to geek out and get more accurate results?
To dig deeper and find your personal protein sweet spot on Keto, you can test your limits using a ketone meter.
To do this, start by reducing your carb count to below 20 g/d for 7-10 days, aiming to enter fairly deep ketosis. Then measure your ketone levels:
- If you're already in ketosis (ketones are above 0.5 mmol/L), gradually up your protein intake until it knocks you out of ketosis. That number is your upper limit for Keto, so look to eat slightly less than that moving forward.
- If you're not in a ketogenic state after the 7-10 days (ketones are below 0.5 mmol/L) then gradually reduce your protein intake to find your sweet spot.
Who Requires a Higher Protein Intake?
The ideal protein consumption on Keto can vary from person to person and depends on a number of factors. Those who may require a higher protein intake include:
1) People looking to maintain muscles mass while losing weight
If you're aiming to lose weight healthily, ideally you want to reduce your body fat percentage while preserving as much lean muscle mass as possible.
Protein intake could play an important role here, as research suggest that diets containing 18%-25% protein can result in greater muscle maintenance when compared to lower protein diets (at 10–12% protein) [*].
Another study demonstrated that a moderate to high protein intake at 1.2 g/kg of body weight was shown to prevent muscle loss over a 4-week period when combined with calorie-restriction and resistance training [*].
Interestingly, research also demonstrated that people who consumed 2.4 g/kg protein per day (3-times the RDA) again combined with resistance training and a calorie-restricted diet, saw an INCREASE in muscle mass over a 4-week period [*].
2) Anyone at risk of slow wound healing
Protein is an essential component in proper wound healing, and experts estimate that consuming 1-3 g protein per kg of body weight is ideal to support the process [*].
This is worth noting for anyone recovering from surgery, healing from post-traumatic wounds, or managing diabetic ulcers.
3) Older adults looking to remain active and healthy
As we enter our golden years, maintaining muscle mass becomes increasingly important. After all, we know that sarcopenia (the loss of muscle with age) is associated with a significantly higher risk of falls and fractures [*].
The good news? Research suggests that higher protein intakes for the elderly (more than 20% of calories from protein) can help maintain muscle mass and physical function [*].
4) Type 2 diabetics and those with cardiovascular risk factors
A 2006 study demonstrated that a high-protein diet (30% of calories from protein) was effective in improving glucose control and insulin sensitivity in men with type 2 diabetes [*].
Similar recommendations have been made for those looking to maintain a healthy heart. A 2017 study demonstrated that in children aged between 2-18 years, a diet containing ~20% of calories from protein provided a greater decrease in cardiovascular risk factors (such as blood pressure and cholesterol) compared to 16% protein. Higher protein intakes were also associated with beneficial cardiovascular outcomes in adults [*].
Bottom line: Use 1.6 g protein per kg of body weight (or 20-30% of calories from protein) as a rule of thumb, but know that you may need to be flexible and adjust your protein intake slightly based on your individual needs.
Do I Need More Protein if I Train Really Hard?
While protein intake is important to fuel muscle growth and repair, research suggests that you don't need to go crazy.
A study in the ’80s followed elite bodybuilders who trained 90 mins a day, 6 days a week. When it came to benefiting body composition, the upper limit of protein intake was 0.75 g/lb (1.65 g/kg) [*]. In fact, it’s well documented that more advanced trainees may require less protein than novice athletes [*].
It’s important to note that this figure of 1.65 g/kg would be the upper limit for muscle gains if you are in a caloric balance (not aiming for weight loss).
However, as we touched on earlier, if you’re consuming a caloric deficit and looking to lose weight, you may benefit from a higher protein intake to help preserve or build lean muscle mass - upwards of 2.4 to 3 g/kg per day [*].
What About Resistance Training and the Keto Diet?
A more recent paper looked at the efficacy of ketogenic diet on body composition during resistance training in trained men.
Researchers found that over an eight-week period, participants were able to lose body fat with no loss of muscle mass. This was achieved while consuming a Keto diet at a calorie surplus and ingesting 2 g protein per kg of body weight [*].
Based on this and previous studies, anywhere between 1.6-3 g/kg would likely be sufficient for the most active individuals amongst you.
Great Keto-Friendly Protein Sources
We’ve established that getting enough protein is important on Keto, but not all sources are created equally.
The overconsumption of processed meats, for example, has been linked with a whole host of health issues, including a potential increase in the risk of heart disease and all-cause mortality [*]
Keto Protein Sources to Limit or Avoid:
- Salami
- Deli meats
- Sausages
- Overly processed bacon
- Corned beef
- Hot dogs
- Lunchmeat
- Jerky
- Fast food
Healthier, Keto-friendly Protein Sources:
- Grass-fed meats
- Free-range poultry
- Wild-caught fish
- Game
- Organ meats
- Full-fat dairy - if tolerated
- Bone broth
- Eggs
- Nuts
- Seeds
If you struggle to hit your protein intake through whole foods alone, you could also consider supplementing with collagen or whey protein if tolerated.
