Does Eating Protein Before Bed Have Health Benefits?

One common question I get from individuals looking to eat healthier and gain muscle is whether they should be eating protein before bed. 

Let’s discuss it!

Importance of protein and muscle mass

Protein is an important nutrient that has numerous roles in the body, including building lean body mass – a.k.a muscle. 

What you might not realize is that our muscle proteins are constantly being broken down and synthesized (built back up). And this balance between the rate of breakdown and building is important as it determines how much muscle mass and strength we have. 

Both getting adequate protein in our diets and doing resistance workouts are needed to support muscle growth and repair.

And they become especially important as we age, as our bodies begin to break down muscle more quickly and become less efficient at synthesizing muscle protein.

This is why, despite calorie needs going down, our protein needs actually increase when we’re older. 

Now, even if you aren’t looking to become a competitive bodybuilder, increasing your lean body mass has many advantages: 

• Burns more calories at rest, helping to maintain a healthy body weight. 
• May help prevent insulin resistance. 
• Helps prevent injury and protects bone mass.
• Improves athletic performance.
• Can help you look more toned. 

Plus, as we get older, having adequate muscle stores can help us live independently for longer and improve recovery time should we get sick or injured. 

So while it’s clear that having adequate muscle mass is important, why do some claim that eating protein soon before bed has particular advantages when it comes to supporting muscle growth?

Why eating protein before bed is thought to be beneficial 

Some of the proposed benefits of eating protein before bed include: 

• Increased muscle repair and growth. 
• Slowed down muscle loss, especially in older adults. 
• Improved performance at the gym by increasing muscle endurance and strength.
• Reduced appetite in the morning. 
• Increased resting energy expenditure (the number of calories you burn while at rest). 

While all these sound great, you may wonder if nighttime protein results in all these benefits.

Research on eating protein before you go to sleep 

Before we get into the research, the major takeaways on whether eating protein before bed is beneficial depend on a few variables: 

• Age
• Amount of protein consumed
• Working out at night
• Desired benefit

This last point refers to what benefit you’re hoping to get from nighttime protein, as — spoiler — research hasn’t found consuming protein before bed to have all the benefits listed earlier. 

It’s also important to note that most of the research on protein before bed uses casein supplements. Casein is a type of protein found in milk that’s more slowly absorbed than whey (the other main protein in milk).

For more on different types of proteins, check out our previous article.

Okay, with all this in mind, let’s look at each group of potential benefits. 

Does eating protein before bed reduce appetite or increase calorie burning? 

Some studies have found a reduction in appetite the following morning after eating protein before bed. However, the research overall has not found a before-bed protein snack to result in a significant reduction in appetite at breakfast.

As for increases in resting energy expenditure, the research is mixed.

While some studies have found an increase in resting metabolic rate the next morning, other studies have found no significant differences. 

Overall, if you’re trying to lose weight, I wouldn’t count on your nighttime protein snack helping to burn more calories or make you less hungry in the morning.

Instead, make sure to account for the calories from your protein snack in your daily eating plan to avoid going over your calorie goals.

Does it improve protein synthesis? 

The simple answer is yes: consuming protein about 30 minutes before bed has been shown to increase muscle protein synthesis overnight. 

However, the amount of protein you eat or drink and whether resistance exercise is done that same night both play a role in how effective consuming protein before bed actually is. 

Studies suggest that if you don’t work out in the evening, individuals, on average, need to consume about 40 grams of slowly digesting protein to notice a significant increase in protein building overnight (1, 2). 

Now keep in mind that many of these studies are smaller in size and are often in men, so it’s hard to say if 40 grams is also the most effective amount for women. 

Still, 40 grams of protein is a lot, especially at night and for older adults who may be noticing a decline in appetite as they age.

The good news is that while 40 grams is the amount to increase protein synthesis, 30 grams has still been shown to at least help prevent muscle breakdown overnight.

Additionally, one study found that doing a resistance workout in the evening and then having a protein supplement before bed increased how efficiently the body was able to use the ingested protein overnight. 

While more research is needed, this suggests that if you work out in the evening, you may be able to have muscle-boosting results with a lower dose of protein.

But what does all this mean for actual muscle growth? And as most of the studies mentioned above were short in duration, what happens when protein is consumed at night for a longer period of time? Let’s keep going!

What about muscle growth and athletic performance at the gym? 

In one study 40 men in their 20’s were assigned to a 12-week resistance program. One group was given a supplement containing 27 grams of protein every night before bed, and the other was given a calorie-free placebo. 

While both groups experienced improvements in muscle strength and size, those given the protein supplement noticed significantly greater gains. 

Now, before you go and start drinking protein shakes every night, a similar 12-week study was done but in men in their 70s.

At the end of this study, both groups increased their muscle mass and strength. However, there was no difference between those given the protein supplement before bed and those given the placebo. 

One thing to note is the protein drink for this study contained only 21 grams of protein, which based on the research we discussed earlier, may have not been enough to cause a significant difference. 

Still, while 30 grams of protein before bed and a regular resistance workout may help increase muscle size and strength in younger adults, more research is needed overall in different age groups and in women. 

The big question: is it the timing or the additional protein that really makes a difference? 

Another difficulty with these studies is that many don’t account for overall protein intake during the day. 

As I talked about in our article on protein pacing, spreading your protein intake evenly throughout the day — rather than eating most of it at dinner — has been shown to be effective for losing weight and improving lean body mass. 

So, when it comes to consuming protein at night, the big question remains: is it the timing of consuming protein at night that matters? Or is overall protein intake spaced evenly throughout the day what’s most important? 

One small study examined this question.

In the study, 13 men participated in a 10-week exercise program in which they all consumed 1.8 grams of protein per kilogram of body weight. They were also given 35 grams of additional casein before bed or earlier in the day. 

At the end of the study, both groups experienced significant improvements in lean body mass, muscle size, and muscle strength, with no significant difference between groups. 

While more research is needed, this study suggests that the benefits of having protein before bed may simply be due to increasing and spreading your protein during the day.

The bottom line

Consuming 30 to 40 grams of slow-digesting protein, like casein, before bed has been shown to support protein synthesis.

It may also help increase muscle growth and strength when combined with an exercise routine that regularly includes resistance training.

Still, until we know more, the most important thing is getting adequate protein throughout the day and spacing your protein intake evenly between meals and snacks. 

If you want to try adding a protein supplement or high-protein snack before bed, account for the extra calories during the day if you’re also trying to lose weight. 

Unsure of how much protein you consume during the day? Be sure to use your Lose It! App to help make sure that you’re getting adequate protein at each meal and snack! 

Curious to learn more about protein needs and protein pacing? Check out our previous articles next: 

• Protein — How Much Do We Actually Need? 
• What is the Protein Pacing Diet?