What it is
Protein is one of the three major macronutrients, along with carbohydrate and dietary fat. A macronutrient is a nutrient you need to consume in relatively large quantities to meet your body’s needs.
What it does
Proteins are the tools that actually do most of the interesting things any biological organism does. Proteins are responsible for muscle contraction, for extracting energy from food, for regulating heart contractility, for regulating gene expression, and for literally millions of other important functions.
Your body is constantly breaking down old proteins and building new proteins. For this process to proceed smoothly, and for protein synthesis to match (or exceed) protein breakdown, you need to consume a sufficient amount of dietary protein. Dietary protein is composed of amino acids, which are the basic building blocks of all proteins.
Recommended intake
The recommended protein intake (RDA) for general health and well-being is 0.8g of protein per kilogram of body mass (about 0.36g per pound) for most populations. However, higher levels of protein intake are helpful for building muscle, or maintaining muscle mass when you’re in an energy deficit. Furthermore, people who exercise more generally require higher protein intakes than people with more sedentary lifestyles.
If you’re on a coached program in MacroFactor, your protein recommendations on your current macro program should be appropriate for your lifestyle, while also accommodating your preferences. The “low” and “high” protein options correspond with the bottom and top of the range of advisable protein intakes for building or maintaining muscle mass, and the “moderate” protein option corresponds with the middle of the optimal range.
If you’re on a collaborative or manual program, intakes in the range of 1.2-2.2g per kilogram (0.55-1.0g per pound) of body mass are generally advisable. If you’re less active and/or maintaining or gaining weight, you might want to be closer to the bottom of that range; if you’re more active and/or losing weight, you might want to be closer to the top of that range.
Likelihood of tracking completeness: Very high
Virtually all foods in the MacroFactor database contain protein information, so it should be easy to accurately track your protein intake with consistent food logging.
For more on the likelihood of tracking completeness, check out this article.
Likelihood of insufficient intake: Very low (for general health)
The vast majority of people in developed countries are able to achieve sufficient protein intake for general health (0.8g/kg). However, some people may find it challenging to consume sufficient protein intakes for maximizing muscle mass, especially when losing weight (since total energy intake is lower, but protein needs are generally higher).
For more on nutrients with a greater likelihood of insufficient or excessive intake, check out this article.
Signs of deficiency/insufficiency
Protein intakes that are insufficient for maximizing muscle gain and retention, but still above the RDA for protein (intakes between 0.8 and 1.2g/kg) are unlikely to have any serious negative consequences. You’ll likely build muscle a bit slower, lose a bit more muscle when losing weight, and be a bit hungrier than you would be otherwise (since protein is generally quite satiating), but those effects are all easily reversible, and they’re not particularly serious effects in the grand scheme of things.
The early signs of insufficient protein intake (below 0.8g/kg) are quite non-specific, including more brittle hair, decreased skin elasticity, increased hunger, and higher rates of minor illnesses. However, those effects could also be the result of poor sleep, excessive stress, excessive exercise, being in a large energy deficit (even if protein intake is adequate), or any number of other causes.
Protein deficiency generally causes more serious effects, including muscle wasting, severe anemia, infertility, and generalized swelling (pitting edema).
If you’re concerned you may have a protein deficiency, seek screening and assistance from a medical doctor or registered dietician.
Good sources
Many animal-based foods are high in protein – meat, dairy, eggs, fish, etc. If you’re struggling to achieve your recommended protein intake without exceeding your calorie target, you may need to focus on lower-fat protein options. For example, chicken breast instead of chicken thighs, tuna instead of salmon, egg whites instead of whole eggs, low-fat dairy instead of full-fat dairy, etc.
There are plenty of great plant-based protein sources as well. Soy products (tofu, tempeh, edamame, etc.), mycoprotein (proteins from fungi, which generally have a complete amino acid profile), quinoa, and buckwheat all have complete proteins, meaning they don’t lack any of the essential amino acids. Beans and peas also offer a lot of protein per calorie compared to most other plant-based protein sources. However, if you have a plant-based diet and a relatively high protein target, it may be challenging to meet your protein target without supplementation. Soy protein supplements and supplements with a blend of pea and rice proteins are both great options that offer a complete amino acid profile.
Learn more
If you’d like to read more about protein, you might enjoy this article from the knowledge base.