Protein is an important nutrient that needs to be consumed on a regular basis. This is the Diet Doctor policy for how much protein we recommend.
We recommend that you choose unprocessed meat, poultry, seafood, eggs and/or dairy as protein sources. Consuming animal products helps ensure that you receive all of the essential amino acids your body needs.
Lacto-ovo vegetarian low-carbohydrate diets are a definitive option, and even vegan low-carbohydrate diets are possible. However, consistently meeting protein and other nutrient needs can be quite challenging for vegans, particularly those who eat very-low-carb or ketogenic diets.
Unlike fat and carbohydrates, protein isn't used as a primary energy source under normal circumstances. Instead, it is used to build and maintain muscle and to replenish the amino acid supply used to make enzymes, hormones, and other tissues in addition to muscle.
Furthermore, there is a limited amount of protein that can be absorbed at a meal. If you eat more protein than your body can absorb, the resulting excess amino acids may instead be used for gluconeogenesis (literally "making new glucose"). Protein may also raise insulin levels when consumed in large amounts. However, this hasn't been tested in many people other than in small studies. Protein's effect on insulin may vary significantly from person to person.
Additionally, gram for gram, protein is considerably more expensive than natural fats like butter, olive oil and coconut oil.
For these reasons, we recommend eating a low-carbohydrate, high-fat diet that is moderate in protein. This goes for all levels of carb restriction.
We define "moderate" protein as roughly 1.2 to 1.7 grams per kilogram (g/kg) of ideal body weight per day for adults. Protein intake within this range has been shown to preserve muscle mass, improve body composition, and provide other health benefits in people who eat low-carb diets or higher-carb diets.
Although this is at least 50% higher than the minimum Recommended Daily Allowance (RDA) for protein of 0.8 g/kg of body weight, it is less than "high-protein" diets containing more than 2 g/kg of protein per day, an amount that is only beneficial when needs are truly increased, such as healing from major injury or surgery.
