“Don’t eat before going to bed. It will make you fat!”
I’m sure we’ve all heard this statement once or twice from less than credible sources, but this statement couldn’t be further from the truth. It completely ignores the principles of meal composition, meal timing, and daily caloric intake. In this article, we will discuss how pre-bedtime meals, specifically those high in protein, can aid in maximizing your progress in the gym.
Muscle Protein Synthesis and Protein Timing
Before diving into pre-bedtime nutrition, it is important to discuss muscle protein synthesis and protein timing. Studies indicate that 30-40 grams of high quality protein is sufficient to maximally stimulate muscle protein synthesis. Muscle protein synthesis is the anabolic process by which our bodies use amino acids to make new proteins, allowing us to build bigger muscles.
Ideally, we want to have elevated levels of muscle protein synthesis for as long as possible throughout the day in order to remain in an anabolic state. Consuming more than the aforementioned amounts of protein in one sitting doesn’t necessarily mean more muscle protein synthesis. If you consume about 1g of protein per pound of body weight and you weigh 200lb, muscle protein synthesis will be elevated longer throughout the day if you consume 5-6 meals containing 30-40g of protein each rather than consuming two meals with 100g of protein each.
A study conducted by Areta et al. illustrated this exact point. This group of scientists wanted to analyze the levels of muscle protein synthesis throughout a 12-hour period following a bout of resistance exercise. Three groups were studied; bolus which consumed 2x40g of protein every six hours, intermediate which consumed 4x20g of protein every three hours, and pulse which consumed 8x10g of protein every hour. The results showed that the intermediate group had significantly higher muscle protein synthesis throughout the 12 hours when compared to the other two groups.  These results reinforce that protein timing and distribution is crucial.
A question that may arise is that if more frequent protein intake is superior, then why did the intermediate group have elevated protein synthesis when compared to the pulse group who consumed 10g protein hourly? Research is indicating that there may be a minimum threshold needed to stimulate adequate muscle protein synthesis. Thus, the 10g consumed hourly by the pulse group may not be sufficient protein to optimally stimulate muscle protein synthesis.
Next, let us discuss what happens when we sleep. Sleep is a form of recovery. Our bodies are in a completely parasympathetic state where we are resting and recovering from our daily activity. This includes muscular rest and recovery as well. On average, sleep takes up about a third of our day, which is a long time to go without any food. Some people even stop eating two to three hours prior to going to bed, which is an even longer period of time without proper nutrition leading to a state of catabolism. Typically, the lack of circulating amino acids in the blood limits the body’s ability to repair and build muscle while at sleep. Thus, it is essential to provide our body with sufficient nutrients prior to sleep in order to repair and recover our muscles from previous exercise.
Meals high in protein prior to sleep can help elevate muscle protein synthesis for prolonged periods of time when compared to no protein consumption prior to sleep. A question that must be answered first is whether or not the body absorbs and uses protein efficiently during sleep similarly as it would during the day.
A study by Kouw et al. answered this question. They wanted to see whether consuming protein prior to bedtime would elevate muscle protein synthesis in older men. It is known that muscle protein synthesis is blunted with aging as a response to both blunted signaling, and decreased protein absorption. Four groups were established in the study; 40g casein prior to sleep, 20g casein prior to sleep, 20g casein + 1.5g leucine, and a placebo group who did not receive any protein prior to sleep. The results from the study showed that the group consuming 40g of casein was the only group that significantly increased levels of protein synthesis compared to the placebo group. This may be due to the fact that older males require a higher protein intake to stimulate protein synthesis to the same degree as younger males, which may be why the groups consuming 20g protein did not see significant increases in muscle protein synthesis.
It would be interesting to see the same study design on younger adults to see if the 20g of protein is effective in this population. Nonetheless, the study was able to effectively illustrate that protein consumed prior to bedtime is effectively absorbed and used by our bodies similarly as it would be during the day-time, and elevates levels of muscle protein synthesis.
Now that we know that protein is effectively used by the body during sleep, another important factor to consider is what should you actually consume prior to bedtime. Many sports performance labs have evaluated the effects of various meal compositions and their effects on various performance related outcomes. Overall, the conclusions we can draw from these studies are that protein consumption on its own is anabolic, but protein plus carbohydrate consumption is superior.  Most of the studies evaluating the effects of mixed meal compositions on muscle protein synthesis have not been conducted pre-bedtime and more so after exercise.
There are a lack of studies evaluating the effects of mixed meal composition prior to bedtime. This might be due to the fact that carbohydrate ingestion prior to sleep will not greatly aid in recovery in the same manner it would directly after a bout of exercise. However, it would be interesting to see if there is some sort of benefit to carbohydrate consumption with protein before bed.
Another factor to consider is what type of protein you should consume. Most importantly, you need to be consuming a complete protein. A complete protein is one that contains all nine essential amino acids. We won’t get into much detail about this, but pretty much any animal sourced protein will be a complete protein, as well as some plant sourced proteins such as soy and pea proteins (although, in my opinion, plant sourced protein tastes horrible).
Next, we need to consider what kind of complete protein to consume. This is being extremely nitpicky, and it is important to say that there are minor differences at best between sources of complete protein, but some of us want to make the best possible efforts to assure that our time in the gym is supported with optimal nutrition. It is best to choose a slow digesting protein such as casein over something like whey. There is scientific evidence to show that casein protein has positive effects on morning satiety levels when consumed pre-bedtime when compared to whey protein.  Slower digestion also means there will be protein available for your body to use for a longer period of time compared to a faster digesting protein such as whey.
- Protein timing and distribution is important to optimize levels of muscle protein synthesis.
- Protein is effectively digested and absorbed during sleep.
- Consuming food before bed will not make you fat! It can actually help with satiety, recovery, and performance.
- The composition of your meal is important, carbohydrate with protein may have beneficial effects although not conclusive.
- Go knock back some protein shakes before bed and make optimal gains!
- Kouw, Imre Wk, et al. “Protein Ingestion before Sleep Increases Overnight Muscle Protein Synthesis Rates in Healthy Older Men: A Randomized Controlled Trial.” The Journal of Nutrition, vol. 147, no. 12, 2017, pp. 2252–2261., doi:10.3945/jn.117.254532.
- Areta, José L., et al. “Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis.” The Journal of Physiology, vol. 591, no. 9, May 2013, pp. 2319–2331., doi:10.1113/jphysiol.2012.244897.
- Ormsbee, Michael J., et al. “The influence of nighttime feeding of carbohydrate or protein combined with exercise training on appetite and cardiometabolic risk in young obese women.” Applied Physiology, Nutrition, and Metabolism, vol. 40, no. 1, 2015, pp. 37–45., doi:10.1139/apnm-2014-0256.
- Wang, Wanyi, et al. “Co-Ingestion of carbohydrate and whey protein increases fasted rates of muscle protein synthesis immediately after resistance exercise in rats.” Plos One, vol. 12, no. 3, 2017, doi:10.1371/journal.pone.0173809.