Can Too Much Protein Kick You Out of Ketosis?
Research shows that protein is important for your overall health. It serves a number of functions, including growth, structure, recovery from injury, fluid balance, and energy production. Therefore, a low protein intake can sometimes lead to health problems.
However, the question of whether too much protein can kick you out of ketosis is a common one in the keto community since protein can be used by your body to produce glucose during low-carbohydrate intake through a process called gluconeogenesis. [1]
Because of this, some people worry that ingesting too much protein will cause them to backslide by removing them from the state of ketosis. Let’s look at whether this is possible and how much protein makes sense for those living a keto lifestyle.
The Role of Protein in Keto
Protein can help ketogenic dieters in the following ways:
Preserves muscle during weight loss
Losing weight while on keto (or any other diet) can put you at risk for muscle loss. This is especially true if you lose weight too quickly. Older adults, in particular, may experience accelerated sarcopenia which could limit their mobility and result in fractures. [2]
Getting adequate amounts of protein during weight loss preserves muscle mass, in addition to strength or weight training.Â
Helps with weight management
Eating enough protein makes it possible to keep the weight off after losing it on keto, especially if used in conjunction with other strategies like exercise and stress management. Protein sets you up for weight loss maintenance success by:
- Increasing your satiety. Research shows that it’s more effective for satiety than carbs and fat. [3]
- Boosting your metabolism and increasing the number of calories you burn. Your body burns about 20-30% of the protein you consume in order to process that protein. [4]
Prevents hair lossÂ
Some people experience hair loss on keto due to missing out on key micronutrients (vitamins and minerals), consuming too few calories, and lack of protein.Â
Paying attention to the quality of your keto diet, which includes consuming enough protein, can prevent hair loss from happening in the first place. [5]
Can Too Much Protein Kick You Out of Ketosis?
The answer to the question of whether too much protein bumps you out of ketosis is it depends. Some people find that higher amounts of protein interfere with their ability to maintain ketosis, while others can tolerate more protein without problems.Â
You may have heard that gluconeogenesis—in which your body makes glucose from non-carb sources—increases during high protein consumption. This idea makes some keto dieters fearful of protein.
The reality is that gluconeogenesis happens continuously, regardless of your protein intake, because certain tissues in your body rely exclusively on glucose. These include your red blood cells, renal medulla (the innermost part of your kidney), and testes. [6] When you are not consuming carbs that are easily converted to glucose, the body uses this method to produce glucose.
In other words, gluconeogenesis makes it possible to maintain a state of ketosis by ensuring that glucose-dependent tissues don’t malfunction.Â
But here’s something you should also know:Â
Too much protein may decrease your ketone levels since protein has a moderate insulin-stimulating effect. (In situations where insulin increases, fatty oxidation decreases, which inhibits ketone production.) [7] Furthermore, research suggests that the amino acid alanine may be antiketogenic—meaning, it suppresses ketone production. [8] [9]
Additionally, research shows that protein has a minimal effect on blood glucose in people with adequate insulin. In contrast, those with insulin deficiency, which is the case with diabetic individuals, may get kicked out of ketosis by eating too much protein. [10]
The more insulin-sensitive you are (meaning, you’re not at risk for diabetes), the less likely your insulin is to increase after eating a protein-rich meal.Â
How high can I go with dietary protein without getting kicked out of ketosis?Â
Good question. The best way to figure out your ideal protein intake—if you’re aiming for a high-protein version of keto—is to test your personal tolerance. Follow these tips:Â
- Calculate your keto macros manually or use a keto calculator for convenience. Note that a standard keto diet uses the following percentages: 60% fat, 30% protein, 10% carbs. [11]
- Consume the recommended grams of protein per day, along with carbs and fat, and then check your ketone levels for a few days. Optimal ketone levels range from 0.5 to 3.0 millimoles per liter. (Blood ketone meters are more accurate than urine strips and breath meters. However, urine strips are less expensive and highly convenient).
- Gradually increase your protein intake and check your ketone levels. Did they drop below 0.5 mmol/L? Continue doing this until you figure out your upper limit for remaining in ketosis.Â
How Much Protein Should You Eat on a Keto Diet?
Aside from the recommended grams of protein you get from a keto calculator, a common recommendation for losing weight or gaining muscle is to aim for between 0.73 and 1 gram of protein per pound of bodyweight. [12] [13]
Individuals who are highly active, heavy exercisers, lifting weights, at an advanced age, or recovering from an illness or injury will benefit from a higher protein intake. Those who are diabetic or prediabetic may benefit from the consumption of slightly lower levels of protein.
Again, if you’re concerned about ketosis, don’t hesitate to check your ketone levels. Â
Healthy Sources of Protein on Keto
Fortunately, there are plenty of foods to choose from that will satisfy your protein needs on keto. Some options are leaner (high-protein but low-fat) while others contain fats and small amounts of carbs:
- Chicken breast
- Whole eggs
- Steak
- Ground meatsÂ
- Fish and seafood
- Cheese
- Almond nuts
- Full-fat dairy
- Bone brothÂ
If you’re struggling to meet your protein (if you’re on a plant-based or vegan keto diet, for example), consider adding a keto-friendly protein supplement to your routine.Â
Finding Your Ideal Personal Protein Level
Protein intake is a controversial topic in the keto diet community. This may cause beginner keto dieters to undereat protein and suffer the consequences, such as muscle loss, hair loss, feeling hungry often, and accelerated sarcopenia.Â
It’s important to remember that gluconeogenesis isn’t something to be afraid of because it keeps our bodies functioning normally while we’re in ketosis.Â
As a general guideline, stay within your recommended protein range (30% of your daily calories if you’re following a standard keto diet) or between 0.73 and 1 gram of protein per pound of bodyweight. You may need more protein if you’re older, recovering from an injury or illness, are an athlete, or live an active lifestyle.Â
As long as you’re not undereating protein, feel free to experiment with varying your protein intake and measuring your ketones to gain insight into your personal limit.Â
References
Fromentin, C., Tomé, D., Nau, F., Flet, L., Luengo, C., Azzout-Marniche, D., Sanders, P., Fromentin, G., & Gaudichon, C. (2013). Dietary proteins contribute little to glucose production, even under optimal gluconeogenic conditions in healthy humans. Diabetes, 62(5), 1435–1442. https://doi.org/10.2337/db12-1208
Verreijen, A.M., Engberink, M.F., Memelink, R.G. et al. (2017). Effect of a high protein diet and/or resistance exercise on the preservation of fat free mass during weight loss in overweight and obese older adults: a randomized controlled trial. Nutr J, 16(10), https://doi.org/10.1186/s12937-017-0229-6
Morell, P., Fiszman, S. (2017). Revisiting the role of protein-induced satiation and satiety. Food Hyd, 68, 199-210. https://doi.org/10.1016/j.foodhyd.2016.08.003
Westerterp K. R. (2004). Diet induced thermogenesis. Nutrition & metabolism, 1(1), 5. https://doi.org/10.1186/1743-7075-1-5
Guo, E. L., & Katta, R. (2017). Diet and hair loss: effects of nutrient deficiency and supplement use. Dermatology practical & conceptual, 7(1), 1–10. https://doi.org/10.5826/dpc.0701a01
Chourpiliadis C, Mohiuddin SS. Biochemistry, Gluconeogenesis. [Updated 2021 Aug 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK544346/
Phinney, S., Volek, J., Volk, B. (2018). How Much Protein Do You Need In Nutritional Ketosis? Virta Health. https://www.virtahealth.com/blog/how-much-protein-on-keto
Nosadini, R., Alberti, K.G.M.M., Johnston, D.G., Del Prato, S., Marescotti, C., Duner, E. (1981). The antiketogenic effect of alanine in normal man: Evidence for an alanine-ketone body cycle. 30(6), 563-567. https://doi.org/10.1016/0026-0495(81)90131-1
Soto-Mota, A., Norwitz, N.G., Evans, R.D., Clarke, K. (2021). Exogenous d-β-hydroxybutyrate lowers blood glucose in part by decreasing the availability of L-alanine for gluconeogenesis. 5(1). https://doi.org/10.1002/edm2.300
Franz M. J. (1997). Protein: metabolism and effect on blood glucose levels. The Diabetes Educator, 23(6), 643–651. https://doi.org/10.1177/014572179702300603
Masood W, Annamaraju P, Uppaluri KR. Ketogenic Diet. [Updated 2021 Nov 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK499830/
Dieter, B. Protein and Weight Loss: How Much Protein Do You Need to Eat Per Day? NASM. https://blog.nasm.org/nutrition/how-much-protein-should-you-eat-per-day-for-weight-loss
Schoenfeld, B. J., & Aragon, A. A. (2018). How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution. Journal of the International Society of Sports Nutrition, 15, 10. https://doi.org/10.1186/s12970-018-0215-1
