The Ultimate Protein Guide

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By now most of us know the importance of protein when it comes to adding muscle mass and progressively getting stronger. What many people struggle with, however, is the amount and type of protein they should be consuming and why it’s important.

Below you’ll find the answer to the most common questions regarding protein all in one place including quantity, quality, frequency and health impacts among other topics of concern. I wanted to condense as much relevant information on protein as possible so you don’t have to scour the internet to find conflicting answers under multiple websites when you can find it all on one page.

 

 

What is Protein?

 

It is widely misunderstood that protein only serves the purpose of building bigger muscles. The truth is that building bigger muscles is by far its only function. In fact, protein is responsible for the structure, function and regulation of cells, hormones, enzymes, you name it. Essentially, protein is a macronutrient you literally cannot live without.

When protein is consumed it is broken down into amino acids, otherwise known as the ‘building blocks’ of protein. Amino acids are then used for cell regulation, hormone and neurotransmitter synthesis and of course repairing your muscles after a workout.

There are 20 standard amino acids that fall into the essential or non-essential amino acids category. Categorizing these amino acids helps determine which amino acids must come from your diet (essential) and which amino acids can be synthesized in your body (non-essential).

Essential: must come from diet

Non-Essential: synthesized in body

 

 

Does protein quality matter?

 

Plain and simple yes.

Protein quality measures how well the protein in your food when consumed provides essential amino acids. This is measured to ensure your diet is appropriately supporting metabolic homeostasis and tissue growth.

Despite having the ability to synthesize some amino acids in your body, it’s not a bad idea to include all 20 of them in your diet by prioritizing complete sources of protein.

Foods with high protein quality, also known as complete sources of protein, contain all 9 essential amino acids. Complete protein sources are almost entirely animal-based. Unlike animal-based protein, their plant-based protein counterparts do not include all 9 essential amino acids (with the exception of soy).

In fact, many plant-based protein sources may have a large degree of variability among their amino acid profiles. One amino acid in particular, leucine, is incredibly important to consume in order to initiate protein synthesis.

Leucine is one of the three branched-chain amino acids (BCAAs) and is by far more effective at stimulating MPS than the remaining BCAAs isoleucine and valine. Research suggests approximately 2.5g of leucine is enough to stimulate protein synthesis through the mTOR signaling pathway which regulates most anabolic functions in your body. ^[1]

Therefore, if your diet mainly consists of incomplete proteins (plant-based), it is generally recommended to adjust total protein intake and consume protein from a wide variety of plant sources to ensure adequate levels of essential amino acids, especially leucine, to promote hypertrophy.

Complete protein sources:

• eggs
• fish
• red meat (beef, pork, lamb)
• dairy (milk, cheese, whey)
• soy

 

Incomplete protein sources:

• lentils
• chickpeas
• quinoa
• nuts
• beans

 

 

Aids in weight loss

 

At 4 calories per gram, protein has a unique ability to increase satiety among people who consume it. This means, unlike carbohydrates or fats, protein by far reduces hunger and increases the feeling of being full. One way this works is by influencing ghrelin and leptin, also known as the “hunger” hormones.

Despite its many functions, ghrelin is mainly known for its ability to stimulate appetite and increase fat storage. Consuming protein can actually induce prolonged suppression of ghrelin, meaning your appetite will decrease as you become more satiated. ^[2] It’s important to note ghrelin shortly drops after a meal but will increase again before your next meal and while fasting so by no means will one high-protein meal permanently suppress ghrelin.

Additionally, protein is also responsible for increased leptin sensitivity. Leptin is a long-term energy regulating hormone responsible for suppressing further food intake leading to weight loss. ^{[3] [4]} This peptide hormone is secreted by adipose cells and is directly proportional to total body fat mass. This means, the more overall fat you have, the greater the secretion of leptin will be.  After eating, leptin is responsible for decreasing food intake, while increasing metabolic rate, temperature and activity level. Influence on leptin levels is not immediate after a single meal but rather its measurement indicates your fed state after many days.

In your day-to-day life, increased protein intake may help reduce late-night and daytime snack cravings. Naturally, it would make sense to increase protein intake to limit the frequency of meals and serving size ultimately resulting in you getting closer to your weight loss goals.

 

 

Strength & Hypertrophy

 

Contrary to popular belief, your muscles don’t grow at the gym. Your muscles grow during their reparation process. Let’s dive a little deeper into what that means.

Obviously, your muscles won’t grow by simply walking into a gym. You must provide enough of a training stimulus to your muscles to give them a reason to grow in size and strength, but even then this isn’t the exact moment when muscles grow. The training stimulus is only meant to stimulate muscle protein synthesis following resistance training. Actual muscle growth occurs when your body is resting and repairing itself, and what does the body need to do that?

You guessed it – protein!

Whether or not you build muscle is determined by your net protein balance (NPB). Your NPB is determined when you subtract muscle protein breakdown (MPB) from muscle protein synthesis (MPS). In other words:

NPB = MPS – MPB

Muscle protein breakdown (MPB) is exactly what it sounds like. It is a naturally occurring and ongoing process where muscle protein is broken down in response to a combination of resistance training and the absence of food, particularly protein. Unfortunately, MPB is a process that places us in a negative NPB (catabolic state).

On the other hand, muscle protein synthesis (MPS) is also a naturally occurring and ongoing process that is greatly driven by resistance training and adequate protein feedings. MPS places us in a positive NPB (anabolic state).

Without the appropriate nutrition, your muscles cannot keep up with your training routine placing you in a catabolic state. You can lift as many weights as you want, but if you are not consuming adequate amounts of protein to maintain a positive balance tipped in the favor of MPS you will not stimulate hypertrophy and actually lose muscle mass.

 

 

How much protein should I consume?

 

This question has come to the attention of many lifters looking to build and maintain muscle mass.

Currently, the World Health Organization (WHO) has the Recommended Dietary Allowance (RDA) at 0.8g/kg or 0.36g/lb of protein per day. This recommendation may seem ridiculously low since many intermediate and experienced lifters are most likely already consuming 2-4x that amount. The reason why the RDA of protein per day seems so low is because the recommendation isn’t meant to build muscle for the average adult, it’s simply put in place to prevent protein deficiency.

To better address the question of how much protein you should consume, we must cover both frequency and quantity.

 

 

Frequency

 

Protein consumption stimulates muscle protein synthesis. For this reason, many lifters recommend eating protein as frequently as possible. Although not inherently bad advice, research does demonstrate there is a “refractory” period between protein consumption that will not re-stimulate protein synthesis which typically lasts 3-4 hours.^[5]

The findings of this study, and many others, suggest that it’d be in your favor to split protein consumption among multiple meals throughout the day, typically 3-5 meals. This may help achieve the highest number of MPS spikes in a single given day.

As straightforward as this sounds, there are some studies that don’t necessarily support this style of feeding being the most optimal. Studies such as those published in 2019 by Tinsley et al. highlight similar body composition results in female participants who underwent intermittent fasting in the form of time-restricted feeding compared to a control diet while consuming similar amounts of protein throughout the day.^[6]

The question then still remains whether or not the timing of protein feeding impacts muscle growth differently. Fortunately, a new study published in 2020 helps shed some light on the topic.

This study measured strength and lean mass in 26 young healthy men (ages 18-26) following a 12-week resistance training regimen in addition to two different diets. Participants were either assigned to the high protein breakfast group which consisted of 23g of protein for breakfast and 32g of protein for dinner resulting in a more even distribution or a low protein breakfast group where participants were allowed 8g of protein for breakfast but a significantly higher 55g of protein for dinner placing them in the uneven protein distribution group. ^[7]

Despite both groups making gains in strength and lean mass, the high protein breakfast group had slightly greater increases in lean body mass and strength across all five exercises tested making somewhat of a case for distributing protein consumption throughout the day.

The results of this study don’t necessarily mean you shouldn’t eat all of your protein in a single meal or two, but rather, consuming your protein in a more balanced manner throughout the day may simply be a slightly better option if your goal is maximizing strength and hypertrophy.

Keeping this in mind there is overwhelming literature showing time and time again that total daily protein intake is more important than the timing, however, if you can manage both of these variables you may be putting yourself in a more favorable position for muscle and strength gains.

 

 

Quantity

 

Previously in the article where we discussed the differences between animal and plant protein I made the recommendation for protein intake to be anywhere from 1.2 – 2.0 g/kg of body weight. Although this is not necessarily incorrect and may very well work for many people, I realize the explanation for the recommendation is greatly limited and wish to expand on why I’m recommending certain protein ranges.

Although the previous recommendation still stands, I want to break down how much protein is needed for those who are already going to the gym 3-5x a week and are still struggling with how much protein they should be ingesting and why.

How to determine protein intake?

There are various ways to help you determine how much protein you need to consume in order to stimulate hypertrophy. We will discuss 4 different recommendations and discuss why their specific ranges may best work for you.

 

 

Body Weight

 

The most commonly used form of calculating protein intake is through the individual’s body weight. In addition to body weight, we must also make the distinction between an untrained (beginner) and trained (experienced) lifter.

 

 

Untrained: 1.6 g/kg or 0.7g/lb

 

One meta-analysis published in 2017 that reviewed 49 studies with a total of 1863 participants, suggested a protein intake of 1.6g/kg or 0.7g/lb being optimal for hypertrophy. ^[8]

As straightforward as this sounds, the majority of participants were untrained individuals that were on a caloric surplus. This is particularly noteworthy since generally less trained individuals are able to progress further with less protein compared to trained and more experienced lifters. Additionally, all of the participants were on a caloric surplus and did not have to account for limiting caloric intake which is not the case for more advanced lifters looking to cut.

For beginners, the recommendation of 1.6 g/kg or 0.7g/lb of protein is appropriate for stimulating hypertrophy while on a caloric surplus. The study also concluded that consuming protein beyond this recommended amount did not demonstrate any added benefit to fat-free mass.

 

 

Trained: 1.6-2.4 g/kg or 0.7-1.1g/lb

 

This recommendation comes from the same meta-analysis by Morton et al. which puts the daily protein goal of untrained individuals on the lower end of the spectrum and runs up to 2.4kg or 1.1g/lb. ^[9]

As previously stated, individuals who are more experienced and have higher amounts of lean body mass simply require more protein to help maintain and build muscle mass.

One advantage to this recommendation is that it allows you to increase protein content without having to sacrifice other macros such as carbohydrates and fats if you are in a caloric deficit. Additionally, with a recommendation of this range, you don’t have to worry whether or not you’re consuming enough protein to support hypertrophy.

 

 

The 1 gram per pound rule

 

1.0g/lb or 2.2g/kg

For many people consuming 1.0g/lb or 2.2g/kg would be enough for muscle growth and strength progression. The benefit to this rule lies in its simplicity to remember – 1 gram of protein per pound of bodyweight.

Although this rule is simple to remember and certainly an appropriate amount for hypertrophy, one drawback of this rule occurs when dealing with much higher body-fat percentages. For example, an individual weighing 250lb at a 35% body fat would essentially have to consume 250g of protein per day according to the 1 gram per pound rule. This is a large amount of protein to consume in a single day and for most, it is difficult to achieve on a day-to-day basis.

If you’re someone with a higher body-fat percentage you do have the option to calculate your necessary protein intake based on lean body mass alone.

 

Lean Body Mass

 

Lean Body Mass: 2.3 – 3.1g/kg FFM (fat free mass) or 1.0 – 1.4g/lb FFM

This recommended range comes from a 2014 systematic review whose participants were lean and trained individuals.^[10] This approach helps solve the issue of consuming too much protein relative to a high body fat percentage and helps establish a guideline for trained individuals who are undergoing energy-restricted resistance training as the need for more protein increases the leaner you are.

In order to calculate your protein intake, you must first determine your body fat percentage and subtract it from your total body weight to give you your total lean body mass (LBM).

Total Body Fat % – Total Body Weight = LBM

A simple way to calculate your body fat percentage, without having to do a DEXA scan, is by simply looking up images of body fat percentage examples in men or women and being honest with yourself to determine which category you fall into. You don’t necessarily have to be spot on with your body fat percentage but it must be within a reasonable range in order to get an accurate daily protein goal.

Based on the sample population in this study, calculating your daily protein intake using your LBM is one of the best ways to help those looking to lose weight and build muscle at the same time. Building muscle while losing fat is known as body recomposition.

 

 

 

20-25g for max muscle protein synthesis?

 

One frequently cited study published in 2013 by Areta et al. supports the hypothesis of 20-25g of high-quality protein being the max dose of protein every 3 hours to elicit an optimal muscle protein synthetic response. ^[11]

You may notice that 4 separate meals at 20g of protein each amount to only 80g of protein per day. As Dr. Brad Schoenfeld and Dr. Alan Aragon point out this is not enough protein to build or maintain muscle mass. Additionally, this study only used whey protein which has a quick absorption time of 20g in ~2hr.^[12]

Moore et al demonstrated no additional benefit for muscle growth above 20g of protein while Macnaughton et al. suggest a larger dose of up to 40g of protein adds roughly a 20% greater myofibrillar FSR. The reason for the difference in results is that participants in the first study only trained lower body whereas participants in the second study underwent full-body resistance training. This suggests higher doses of protein may be beneficial when more muscle undergoes resistance training.

The amount of protein you do use for muscle-building purposes also has to do with the size of the individual. Generally, a person with more muscle mass may need a slightly larger protein feeding to help maximize MPS. In order to account for differences in size, one study proposed a protein intake of 0.4 g/kg or 0.18g/lb per meal to sufficiently stimulate MPS. Anything beyond this has been proposed to result in no further stimulation of MPS. ^[13] Using this recommendation split into 4-5 meals per day you would see it results in 1.6 – 2.0 g/kg of body weight which matches closely to our trained individual bodyweight recommendation.

As with most things, aging is a process that seems to stack the odds against us. As we age we experience what is known as anabolic resistance. Anabolic resistance is when MPS is reduced to a given dose of protein.^[14] The effects of 160g of protein per day in your 20s may not give the individual the same benefits compared to when they are in their 50s or 60s. If you are more advanced in age additional protein beyond this recommendation may be better from a hypertrophy standpoint.

 

 

How much protein can my body absorb?

 

Here’s one you may have already heard.

“Your body can only absorb 20-25g of protein per meal.”

Now that we’ve discussed how much protein you should be consuming, the next concern stems from a common nutritional myth.

According to a paper published in 2009 on digestion and absorption, healthy individuals absent of any gut disorder can actually absorb all ingested protein.^[15] From a nutritional standpoint, absorption means nutrients that go through the gut and enter the circulatory system. This means you can technically eat 5x as much protein than the suggested amount in one sitting and still absorb it all.

If we are able to absorb all ingested protein, then the next question has to do with whether or not the amino acids from the surplus protein will provide you with any further muscle-building benefit, and the truth is it hardly does.

If you consume 60g of protein for each meal rather than the 20-25g recommendation this doesn’t necessarily mean you’ll get three times the intensity or duration of muscle protein synthesis. Despite the 20-25g of protein recommendation your MPS response may be improved to a minimal degree if you double or even triple that recommendation.

The theory that explains this MPS ceiling even after consuming larger quantities of protein is termed the “muscle full effect.” ^[16] Unfortunately, many of the studies that do not show further improvement in MPS are acute studies that lack the evidence to show if higher doses over a longer period of time have a different outcome.

So what happens with the rest of the protein?

The rest of the protein will still be used. Rates of amino acid oxidation and urea production increase while other amino acids will be used for making hormones, enzymes and other cellular structures.^[17]

In short, yes your body can and will digest higher quantities of protein but it may not all be used for muscle-building purposes, rather your body will still use it to keep you alive.

 

 

Are high protein diets bad?

 

Contrary to widespread skepticism, high protein diets (HPDs) are not dangerous to your health. This claim comes from the suspicion that high amounts of protein can “overload” your kidneys causing them to fail or that it decreases bone density.

According to one research paper that assessed HPDs in 14 males for a period of one year the participants did not show any signs of kidney failure. Do keep in mind however this study was done in participants who overall had well-functioning kidneys. Therefore, it is not safe to assume long-term HPDs are safe for individuals who already have pre-existing kidney health concerns.

Likewise, a separate review from the National Osteoporosis Foundation did not find any negative impacts in bone health when undergoing high protein diets.

As always, I advise talking to your primary care provider if you have additional questions or concerns.

 

 

Can I get big on protein alone?

 

As previously stated protein consumption does stimulate MPS, however, this stimulus does not compare to the one achieved through resistance training. You can eat 300g of protein per day (a bit excessive) and still not get the results you are looking for if you do not train hard enough or at all.

All sets don’t necessarily need to go to failure but must be taken close enough to give your muscles a reason to grow. You won’t get big on protein alone but you also won’t get big if you’re not consuming enough.

 

 

Differences between protein powders

 

Whey

Cow’s milk is made up of two proteins known as whey (20%) and casein (80%).

When milk is processed to make yogurt or cheese, the remaining liquid, or byproduct is both whey and casein. You may have seen this when opening a cup of yogurt and seeing a white-ish liquid resting on the top.

Whey is made up of several fast-digesting proteins that are absorbed quickly at about 10g per hour and can be further processed to increase protein content per serving.

The two most common forms of whey protein are whey concentrate and whey isolate.

Whey Concentrate

When processed the liquid whey is dried to become whey concentrate powder which is made up of 70-80% protein and 20-30% carbohydrates and fats by weight.

The distribution of macronutrients per serving largely depends on the brand. This doesn’t mean whey concentrate is bad or inferior simply because it has carbohydrates and fats, on the contrary, these two macronutrients are necessary for MPS to even take place.

If the idea of less protein per serving is bothersome, you can always increase the serving size. The only downside to this is that you’ll end up finishing your protein powder a lot quicker.

As a dairy protein source, most people who are lactose intolerant or have dairy allergies may want to avoid this variation of whey.

 

Whey Isolate

Unlike whey concentrate, whey isolate requires a different set of processes to achieve a different macronutrient distribution which results in fewer carbohydrates and fats but more protein per serving. In whey isolate, up to 90% or higher of a total serving is protein.

Aside from a lower fat and carbohydrate makeup, whey isolate also offers a reduced lactose content. Reduced lactose content does not mean it is 100% absent, but rather the amount present is so low it is less likely to cause GI problems in individuals who are lactose intolerant.

Due to the higher degree of protein content, whey isolate is more expensive than whey concentrate.

 

Clear Whey Isolate

Clear whey isolate is my personal favorite protein supplement for various reasons.

Similar to whey isolate, it provides all 9 essential amino acids, maintains a high protein percentage and is low in fats and carbohydrates.

The main differences are the variety of flavors it offers compared to the more traditional chocolate, strawberry and vanilla flavors that we’ve been accustomed to.  Additionally, since clear whey isolate is only meant to be mixed with water, it goes well with almost any meal and doesn’t need to be refrigerated. It also mixes well with creatine which I personally add 5g of to all of my shakes.

 

Casein

Unlike whey protein, casein is absorbed at a slower rate. When consuming whey protein, amino acid levels are elevated for 90 minutes whereas with casein your amino acid levels are elevated for 4-5 hours. ^[18]

One positive note on casein is that despite not raising your amino acid levels as high as whey, it still slows down the rate of MPB preventing your muscles from getting smaller. This is due to casein’s slow and steady release of amino acids.

 

Vegan

As the name suggests, vegan protein powders are not derived from animal sources.

From a hypertrophy standpoint, there isn’t a greater benefit to consuming vegan protein powders as opposed to whey other than if you’re vegan of course, and would like to sustain that lifestyle.

Vegan protein powders are generally made from the derivatives of not only one but rather a combination of several plant sources. When dealing with plant-based sources there’s one benefit and drawback that should become apparent.

Since the powder is made from plants, it is generally advertised as lactose-free. This is good news for those that lack the lactase enzyme (lactose-intolerant) and struggle with whey concentrate or even whey isolate protein.

The drawback of vegan protein powders is that despite their average 20-30g of protein per serving, their amino acid composition largely depends on the plant’s sources from which they’re made. In order to compensate for this, some supplement companies may add additional amino acids so your serving contains an adequate ratio of essential amino acids. Of course, this may contribute to their generally higher prices. If you’re considering vegan protein for hypertrophy and strength gains, make sure to do your research and ensure it has all 9 essential amino acids.

 

Disclaimer: The “Price” column is solely based on average processing costs and is not intended to be a 100% accurate representation of protein supplement costs across the market. You may potentially encounter whey concentrate supplements that are more expensive than vegan protein powders. Pricing is ultimately dictated by each brand or company.

 

 

Whey during the day, casein at night?

 

One common belief among the bodybuilding community to maximize muscle building is to consume whey protein during the day and casein right before bedtime. Since casein is a slow-digesting protein it makes sense to stimulate MPS for as long as possible to prevent the possible catabolic effects of not eating while sleeping overnight.

Despite its marketing tactic to appeal to individuals looking to maximize their muscle-building potential in the early days, many acute studies show that 40g of casein before bed was effective at stimulating MPS and improving net protein balance (NPB). ^[19]

Again we are faced with a situation where we have to distinguish acute studies from longitudinal studies. Since significant muscle building happens to be something that takes months to years it’s best to find evidence from studies that best represent that timeframe. So what do longitudinal studies say?

A longitudinal study published in 2018 demonstrated there are no significant differences in body composition, hypertrophy and strength when consuming 35g of casein protein during the day or the night when total daily protein intake is equated.^[20]

It is not absolutely critical to consume protein right before bed including casein. In theory, this could be one of those small adjustable variables that could result in more gains but based on the research your best bet is still total protein intake.

I thought it was bad to eat at night.

There is some evidence pointing to protein consumption before bed having a negative impact on sleep quality and metabolism. This is mainly seen in feedings that are high in calories with the majority of their caloric composition being from fat.^[21]  A feeding that is lower in calories that mainly come from protein and carbohydrates most likely don’t negatively affect sleep quality.^[22]

In fact, some research shows some dairy products may actually improve sleep quality. Here’s where a greek yogurt that’s high in protein before bed isn’t necessarily a bad idea.

I would like to present another argument for why it may be disadvantageous to consume protein before bed. Out of all three macronutrients, protein is the one with the highest thermogenic effect. This means when digesting raises body temperature higher than when digesting fats or carbohydrates. According to the Sleep Foundation, higher temperatures while sleeping may lead to impaired sleep onset and quality.^[23]

Research suggests 30-40g of protein before bed does not negatively impair sleep.^[24]

 

 

Should I worry about the anabolic window?

 

The anabolic window refers to a 30 minute period after resistance training where protein and carbohydrates are most effective.

As previously discussed in a separate article, the anabolic window seems to lack scientific credibility. Research has demonstrated that total protein intake throughout the day is more important for muscle mass and strength progression than timing.

The only potential real-world application for the anabolic window where timing may play a significant role is if you’re training fasted. Considering you spend 8 hours sleeping and an additional 1-2 hours during your workout, it leaves your body with limited supplies to help keep you in a positive net protein balance (NPB). In the case of fasted exercise, it may benefit you to consume protein and carbohydrates sooner rather than later following resistance training exercise to prevent from being in a negative NPB for an extended period of time.

 

 

PHF on the subject

 

There is a lot to break down here so I will try my best to keep things brief.

When picking your next meal try to ensure your protein comes from a complete protein source to obtain all 9 essential amino acids. If your protein mainly comes from plant sources make sure to consume it from various sources to ensure adequate levels of amino acids especially leucine.

Total protein intake takes precedence over the timing but adjusting both may potentially serve you better than only optimizing one variable. If you do decide to equally split your protein content among 4-5 meals ensure you are following the recommendation of 0.4g/kg or 0.18g/lb of protein per meal or follow whichever protein recommendation from the ones listed that aligns with your goals. Aside from protein intake, it is important to note these adjustments will have little impact if your training stimulus is not adequate.

Although there is nothing inherently wrong with whey concentrate or casein protein powders, I personally prefer whey isolate and clear whey isolate protein since they work best with my protein-feeding strategies. If your goal is hypertrophy and you struggle with finding additional protein sources I would avoid vegan protein if at all possible. If you prefer vegan protein powders due to being vegan or because it is the only dairy-free alternative by all means do what best works for you or aligns with your beliefs since you will still be able to make the same gains in strength and hypertrophy as someone who is not following a vegan diet. Choosing this option, however. may mean more work finding protein sources with sufficient amino acid profiles.