When we think about protein, we often associate it with muscle recovery, athletic performance, and satiety. However, emerging research suggests that protein intake may also affect our sleep. From improving sleep quality to reducing sleep disturbances, consuming adequate protein may be a valuable tool for those seeking better rest.
If you're not sure how much sleep you should be getting, and whether you're getting enough, read our article Are you getting enough sleep?
Protein and sleep: what's the connection?
A high-protein diet and sleep patterns appear to have a positive correlation. Protein provides essential amino acids that play a role in neurotransmitter production, helping to regulate mood and relaxation. One amino acid in particular - tryptophan - is a key player in sleep regulation.
Tryptophan and sleep
Tryptophan is a precursor to serotonin, a neurotransmitter that helps produce melatonin, the hormone responsible for regulating our sleep-wake cycle. Consuming protein-rich foods that contain tryptophan may enhance melatonin production, ultimately improving sleep and protein intake balance [1].
Here are some examples of tryptophan-rich foods:
Poultry, meat, and fish
- Turkey & Chicken - ~350-400 mg per 100g
- Beef & Pork - ~250 mg per 100g
- Fish & Seafood
- Salmon & Tuna - ~250-300 mg per 100g
- Other fatty fish (Mackerel, Sardines, Cod) - 200-250 mg per 100g
Dairy and eggs
- Cheese (Cheddar, Parmesan, Mozzarella) - 500-600 mg per 100g
- Milk & greek yoghurt - 50-100 mg per 100g
- Eggs - 150-200 mg per large egg
Plant-based proteins
- Soy products (Tofu, Tempeh, Edamame) - 250-300 mg per 100g
- Legumes (Lentils, Chickpeas, Black Beans) - 100-150 mg per 100g
- Nuts, Seeds & Whole Grains
- Pumpkin Seeds & Sunflower Seeds - 500 mg per 100g
- Sesame Seeds & Tahini - 250-300 mg per 100g
- Almonds, Walnuts, Cashews, Peanuts - 150-250 mg per 100g
- Oats & Whole Grains (Quinoa, Brown Rice, Whole Wheat) - 50-100 mg per 100g
- Dark Chocolate (85%+ Cocoa) - 200 mg per 100g
How much tryptophan do you need for sleep?
The recommended daily intake (RDI) for tryptophan is 250-425 mg per day for an average adult. Some of the best sources can provide this amount in a single serving, for example:
- 100g of turkey = 350 mg
- 30g of pumpkin seeds = 150 mg
- 50g of Parmesan cheese = 300 mg
Blood sugar and sleep
Another area of health where protein intake might potentially affect sleep and sleep quality concerns blood sugar regulation. Blood sugar fluctuations can significantly impact sleep quality: large spikes and crashes in blood glucose levels - often caused by high-carb, low-protein meals - can lead to sleep disturbances, restlessness, and even night-time waking [2].
Protein intake and blood sugar control
One of the key ways that protein and sleep quality are linked is through blood sugar stabilisation. Here's how protein can help regulate blood sugar and improve sleep:
- Prevents blood sugar spikes & crashes
When consumed with carbohydrates, protein slows digestion and the release of glucose into the bloodstream, reducing sharp spikes in blood sugar [3,4]. This helps prevent the night-time blood sugar crashes that can wake you up or cause restless sleep.
- Supports sustained energy release
Pairing protein intake and sleep with balanced macronutrient meals - especially before bed - ensures a slow and steady release of energy, preventing overnight hunger or glucose dips that can lead to night wakings [5].
- Improves insulin sensitivity
A high-protein diet and sleep benefits may also be linked to improved insulin sensitivity, which means better blood sugar regulation throughout the day and night [6].
If you think you might be eating too much sugar, read our blog for some guidance and tips to easily reduce your intake: Are you eating too much sugar?
Protein timing for better sleep
Does it matter when you consume protein to better aid sleep? Let's look at a couple of reasons why meal timing might be significant:
- Protein before bed
Consuming protein powder and sleep-supporting foods before bed may benefit muscle recovery and sleep. Whey protein and sleep benefits have been studied in athletes, with some findings suggesting improved overnight muscle protein synthesis and better recovery [7]. Additionally, there is a lot of interest in casein protein for sleep. It is a slow-digesting protein, so casein protein before bed may help provide a steady release of amino acids throughout the night, reducing muscle breakdown and promoting deeper sleep [8].
- Balanced protein intake throughout the day
We're all different, with different lifestyles. Some people find that distributing protein intake evenly across meals ensures a consistent supply of amino acids, supporting neurotransmitter function and overall sleep and protein balance. Those who consume optimal protein during the day may experience fewer sleep disturbances and higher-quality rest [9].
- The right amount of protein
While protein is essential, excessive intake right before bed, particularly from heavy meals, may cause digestive discomfort, disrupting sleep rather than improving it. It's best to find a balance - consuming an appropriate amount of protein that suits your body's needs. To find out more about how much protein is right for you, read our blog: How much protein do I need?
The verdict: can protein help you sleep?
The evidence suggests that protein intake and sleep may be connected. Whether through its role in neurotransmitter production, its ability to stabilise blood sugar, or its support for muscle recovery overnight, adequate protein intake may improve sleep quality and reduce sleep disturbances. By choosing the right protein sources and timing your intake wisely, you can harness the benefits of protein for better rest and recovery.
If you don't have the time or know-how to ensure you are eating enough protein, why not subscribe to a healthy, high-protein meal prep service like Prep Kitchen? We make healthy eating effortless!
This is an article from our Protein Series. You can see some of the other articles in the series below:
What are the benefits of a high-protein diet?
Should you have protein before or after a workout
How to get enough protein as a vegetarian
Does protein help you lose weight?
Can protein help to support mental health?
References
Clarinda N Sutanto, Wen Wei Loh, Jung Eun Kim, (2022) The impact of tryptophan supplementation on sleep quality: a systematic review, meta-analysis, and meta-regression, Nutrition Reviews, 80:2, 306-316, https://doi.org/10.1093/nutrit/nuab027
Van Cauter, E., Polonsky, K.S., & Scheen, A.J. (1997). Roles of circadian rhythmicity and sleep in human glucose regulation. Endocrine Reviews, 18(5), 716-738.
Nuttall, F.Q., Gannon, M.C. (2003). Metabolic response to a high-protein, low-carbohydrate diet in men with type 2 diabetes mellitus. Metabolism, 52(3), 430-434.
Gannon MC, Nuttall FQ, Saeed A, Jordan K, Hoover H. (2003) An increase in dietary protein improves the blood glucose response in persons with type 2 diabetes. Am J Clin Nutr.Oct;78(4):734-41. doi: 10.1093/ajcn/78.4.734. PMID: 14522731.
Layman, D.K. (2003). The role of leucine in weight loss diets and glucose homeostasis. The Journal of Nutrition, 133(1), 261S-267S.
Gannon, M.C., Nuttall, F.Q., Westphal, S.A., Neil, B.J., & Seaquist, E.R. (2001). Effects of a high-protein, low-carbohydrate diet on blood glucose control in people with type 2 diabetes. Diabetes, 50(1), 113-118.
Snijders, T., Res, P.T., Smeets, J.S.J., van Vliet, S., van Kranenburg, J., Maase, K., Kies, A.K., & van Loon, L.J. C. (2015). Protein ingestion before sleep improves post-exercise overnight recovery. Medicine & Science in Sports & Exercise, 47(7), 1442-1450.
Res, P.T., Groen, B., Pennings, B., Beelen, M., Wallis, G.A., Gijsen, A.P., Senden, J.M., & van Loon, L.J.C. (2012). Protein ingestion before sleep improves overnight muscle protein synthesis rates in healthy older men: a randomized controlled trial. The Journal of Nutrition, 142(7), 1293-1299.
St-Onge, M.P., Mikic, A., & Pietrolungo, C.E. (2016). Effects of diet on sleep quality. Advances in Nutrition, 7(5), 938-949.
Sutanto CN, Loh WW, Toh DWK, Lee DPS, Kim JE. Association Between Dietary Protein Intake and Sleep Quality in Middle-Aged and Older Adults in Singapore. Front Nutr. 2022 Mar 9;9:832341. doi: 10.3389/fnut.2022.832341. PMID: 35356724; PMCID: PMC8959711.
