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Protein isn’t just for gym bros. Yes, the macronutrient has a direct effect on muscle growth, but it also has a ton of other health benefits, from keeping you full to supporting your immune system. 

Proteins are made up of amino acids. When you eat dietary protein, your body breaks it down into these amino acids, and then uses them to rebuild new proteins that carry out various functions and support your body in different ways. Enzymes, antibodies, hormones, and neurotransmitters are all proteins. Every cell in your body contains protein and without it, you would literally fall apart (it holds up your muscles and bones, too).

In this guide, we’ll dig deeper in each of the specific benefits of protein and answer some commonly asked questions about the nutrient.

Medical disclaimer: This article is intended for educational and informational purposes only. It is not intended as a substitute for medical advice. For health advice, contact a licensed healthcare provider.

1. Helps With Muscle Growth

Muscle growth is probably one of the most well-known benefits of protein. You’ll often see bodybuilders and people trying to change their body composition eat high-protein diets for this reason. Muscle growth is officially called “muscle hypertrophy.” 

And according to a December 2019 review published in the International Journal of Environmental Research and Public Health1, muscle hypertrophy relies on the right mix of resistance training and protein consumption. Basically, the formation of new muscle protein has to exceed muscle protein breakdown. It’s only in this net positive state that you can build muscle. And, adequate dietary protein intake helps keep you net positive.

Man pressing Eleiko dumbbells

If you don’t take in enough protein, you run the risk of the reverse: muscle protein breakdown exceeding the formation of new muscle protein. If this happens, it can result in muscle loss.

Timing of that protein may matter, too. Another study published in Nestle Nutrition Institute Workshop Series2 showed that consuming protein 24 hours before or after resistance training could maximize muscle protein synthesis (or the formation of new muscle). This study also called out that 20 to 25 grams of protein in this window seemed to be the sweet spot.

2. Can Help You Get Stronger

Because protein can help you build muscle, it may also make you stronger when combined with proper training. A report published in Sports Medicine3 in 2015 called out that when combined with the right frequency, volume, and duration of resistance training, an adequate (and consistent) protein intake could increase muscle strength. This applied to both trained and untrained people.

3. May Assist With Muscle Recovery

The science isn’t totally settled on whether or not protein can help with muscle recovery and delayed-onset muscle soreness (DOMS), but there’s some research4 that shows it might. 

In one study published in Applied Physiology, Nutrition and Metabolism5 in 2018, researchers instructed 20 active females to consume either a whey protein supplement or an isoenergetic carbohydrate for four days after a workout. 

An image of NOW Sports organic whey protein powder

They measured muscle soreness, muscle function, flexibility, and levels of creatine kinase (an indicator of muscle damage) at 24, 48 and 72 hours post-exercise. The protein group experienced faster recovery in all of the areas.

4. Can Keep Appetite Down

Protein promotes satiety6 more than the other macronutrients. In other words, when your meal contains the right amount of protein, you feel full longer after eating it. That’s because protein decreases ghrelin7, a gut hormone that controls your appetite. When ghrelin levels are high, you feel hungry. When ghrelin levels drop, you feel full. 

Ghrelin production is partly controlled by the amount of food in your stomach, but the macronutrient balance matters, too. Studies8 show that a high-protein breakfast can decrease ghrelin more significantly than a high-carbohydrate one.

This effect on ghrelin can help you balance overall food (and calorie) intake and promote weight loss and/or maintenance.

5. May Help With Weight Loss

Because protein is so filling, it can also indirectly help you lose weight. Let’s be clear: Adding extra protein to your plate in the name of weight loss isn’t going to do the trick. The point is that when you’re meeting your daily needs, you’re less likely to overeat. 

For this reason, research9 shows that high-protein diets can help you lose weight (or manage your body weight) and reduce overall fat mass, specifically. There’s also some evidence that spreading that protein out—consuming around 25 to 30 grams per meal—is extra beneficial. 

And as an added bonus, a high-protein diet may improve various heart disease risk factors, like triglycerides, cholesterol, blood pressure, and waist circumference, too. For the record, a high-protein diet in this case is defined as one that contains 1.2 to 1.6 grams of protein per kilogram of body weight. 

6. Good for Bone Health 

Calcium is often hailed as the reigning nutrient for bone health, but protein contains key nutrients that increase bone mineral density and reduce your risk of osteoporosis. In fact, some researchers10 say that it’s just as essential as calcium and vitamin D for bone health.

According to a 2011 report in the International Journal for Vitamin and Nutrition Research11, a low protein intake, which they define as less than 0.8 grams per kilogram of body weight per day, is often seen in people who are hospitalized with hip fractures. The researchers go on to say that even consuming 0.8 grams per kilogram of body per day (which is the current recommended amount) may be too low for older adults.

7. Supports Neurological Health 

Your central nervous system12, AKA your brain and spinal cord, needs amino acids. Tryptophan, tyrosine, histidine, and arginine, specifically, are used to make neurotransmitters and other neuromodulators, like dopamine, serotonin, acetylcholine, histamine, norepinephrine, and nitric oxide. These compounds play varying roles in your body, but they control everything from your mood to your blood pressure. 

Protein also keeps your brain sharp. In one review published in the American Journal of Clinical Nutrition13 in January 2022, researchers compared rates of cognitive decline in men and women from the Nurses’ Health Study. They found that higher protein intake was connected to lower rates of cognitive decline when compared to taking in the same amount of calories from carbohydrates. 

There’s an important callout here though: The protein has to be from healthy food sources. Higher intakes of beans/legumes, fish, and lean poultry can keep your brain sharp, but relying on hot dogs and other processed protein foods can have the opposite effect. 

RXBAR Protein Bars

This also isn’t to say that you should completely avoid carbs. It just means to make sure you’re including enough high-quality protein-rich foods in your diet and not letting carbs dominate your calorie intake.

8. Supports Hormone Health 

Proteins (and amino acids) are the building blocks of hormones. Making sure you’re getting enough protein is vital to keeping your thyroid working as it should14. Protein also helps your body maintain insulin growth factor 1 (IGF-1) levels15, which is a key component of both the anabolic and catabolic pathways that support muscle growth16.

RELATED: No Cow protein bar review

9. Helps With Healing And Immunity

Your body needs protein to repair muscle, skin, and other body tissues—and it’s essential during wound healing17. Collagen, which is the most abundant protein in your body, regulates the different stages of wound healing18. And scar tissue19 is made primarily of collagen.

Proteins are also essential for your immune system. You need adequate amounts of protein to heal from an illness and/or fight one off. Amino acids regulate T-cells, B-cells, natural killer cells, and macrophages—all white blood cells that fight off infection. They also play a role in the production of antibodies and cytokines, which neutralize viruses and bacteria and can help fight off cancer20 and other diseases.

On the flip side, inadequate protein intake can impair immune function and increase your risk of getting sick.

Benefits of Protein: Final Thoughts 

Yes, protein helps you build muscle, but it does so much more than that, too. Getting enough protein can help you manage your appetite and support weight loss. Protein—and the essential amino acids you get from it—is also critical for brain function, hormone health, and your immune system. When it comes to upping your daily protein, healthy food sources are your best bet, but protein powders can supplement your diet to help you meet your needs.

Benefits of Protein: Q&A

How Much Protein Do You Need A Day?

It depends on your activity level. The current dietary guideline for sedentary folks is 0.8 grams of protein for every kilogram of body weight. That means if you weigh 180 pounds, you’ll need a minimum of 65 grams of protein per day. If you’re active, your protein needs go up from there. The Mayo Clinic21 recommends that people who exercise regularly get 1.1 to 1.5 grams per kilogram. Avid weightlifters and bodybuilders need 1.2 to 1.7 grams per kilogram.

Your needs go up as you age, too. After the age of 30, you risk losing about 3% to 8%22 of your muscle mass per decade. That number increases even more after the age of 60. Because of this, protein needs increase to 1 to 1.2 grams per kilogram at a minimum.

How Do You Know If Your Protein Is Too Low?

Tracking macros is the best way to know if your protein is too low. You don’t necessarily need to follow a specific macro diet. Instead, you can log your food intake to make sure you’re hitting your minimum daily protein goals. If you don’t know how much protein you should be getting, work with a personal trainer, qualified nutritionist, or dietitian to come up with a baseline for you.

You may also be able to tell if your protein is too low by the way you feel. Maybe you’re always hungry or tired. You might be getting sick a lot or have slow-healing injuries. Just keep in mind that while all of these symptoms are connected to low protein, that might not be the actual cause. If you’re having persistent symptoms, check in with your doctor.

Which Foods Have A Lot Of Protein?

Animal-based foods like chicken breast, steak, turkey, eggs, and Greek yogurt, are the most bioavailable23 sources of protein. You can also get protein from plant-based sources, like legumes (beans, peas, lentils, chickpeas and peanuts/peanut butter), seeds, and quinoa. However, research suggests that they may not have the same therapeutic properties as more bioavailable sources.

Whey protein supplements have a lot of protein, too, but as the name suggests, protein shakes should be used to supplement healthy eating—not take the place of it.

References

1. Krzysztofik, M, Wilk, M, Wojdała, G, Gołaś, A. Maximizing muscle hypertrophy: a systematic review of advanced resistance training techniques and methods. Int J Environ Res Public Health. 2019;16(24):4897. doi:10.3390/ijerph16244897

2. Tipton, KD, Phillips, SM. Dietary protein for muscle hypertrophy. Nestle Nutr Inst Workshop Ser. 2013;76:73-84. doi:10.1159/000350259

3. Pasiakos, SM, McLellan, TM, Lieberman, HR. The effects of protein supplements on muscle mass, strength, and aerobic and anaerobic power in healthy adults: a systematic review. Sports Med. 2015;45(1):111-131. doi:10.1007/s40279-014-0242-2

4. Etheridge, T, Philp, A, Watt, PW. A single protein meal increases recovery of muscle function following an acute eccentric exercise bout. Appl Physiol Nutr Metab. 2008;33(3):483-488. doi:10.1139/H08-028

5. Brown, MA, Stevenson, EJ, Howatson, G. Whey protein hydrolysate supplementation accelerates recovery from exercise-induced muscle damage in females. Appl Physiol Nutr Metab. 2018;43(4):324-330. doi:10.1139/apnm-2017-0412

6. Morell, P, Fiszman, S. Revisiting the role of protein-induced satiation and satiety. Food Hydrocoll. 2017;68:199-210. doi:10.1016/j.foodhyd.2016.08.003

7. Kohanmoo, A, Faghih, S, Akhlaghi, M. Effect of short- and long-term protein consumption on appetite and appetite-regulating gastrointestinal hormones, a systematic review and meta-analysis of randomized controlled trials. Physiol Behav. 2020;226:113123. doi:10.1016/j.physbeh.2020.113123

8. Blom, WA, Lluch, A, Stafleu, A, et al. Effect of a high-protein breakfast on the postprandial ghrelin response. Am J Clin Nutr. 2006;83(2):211-220. doi:10.1093/ajcn/83.2.211

9. Leidy, HJ, Clifton, PM, Astrup, A, et al. The role of protein in weight loss and maintenance. Am J Clin Nutr. 2015;101(6):1320S-1329S. doi:10.3945/ajcn.114.084038

10. Bonjour, JP. Dietary protein: an essential nutrient for bone health. J Am Coll Nutr. 2005;24(6 Suppl):526S-36S. doi:10.1080/07315724.2005.10719501

11. Bonjour, JP. Protein intake and bone health. Int J Vitam Nutr Res. 2011;81(2-3):134-142. doi:10.1024/0300-9831/a000063

12. Institute of Medicine (US) Committee on Military Nutrition Research; National Academies Press (US). The role of protein and amino acids in sustaining and enhancing performance. 1999. 

13. Yeh, TS, Yuan, C, Ascherio, A, Rosner, BA, Blacker, D, Willett, WC. Long-term dietary protein intake and subjective cognitive decline in US men and women. Am J Clin Nutr. 2022;115(1):199-210. doi:10.1093/ajcn/nqab236

14. Pałkowska-Goździk, E, Lachowicz, K, Rosołowska-Huszcz, D. Effects of dietary protein on thyroid axis activity. Nutrients. 2017;10(1):5. Published 2017 Dec 22. doi:10.3390/nu10010005

15. Nishi, H, Uchida, K, Saito, M, et al. Essential amino acid intake is required for sustaining serum insulin-like growth factor-I levels but is not necessarily needed for body growth. Cells. 2022;11(9):1523. Published 2022 May 2. doi:10.3390/cells11091523

16. Yoshida, T, Delafontaine, P. Mechanisms of IGF-1-mediated regulation of skeletal muscle hypertrophy and atrophy. Cells. 2020;9(9):1970. Published 2020 Aug 26. doi:10.3390/cells9091970

17. Wang, X, Yu, Z, Zhou, S, Shen, S, Chen, W. The effect of a compound protein on wound healing and nutritional status. Evid Based Complement Alternat Med. 2022;2022:4231516. doi:10.1155/2022/4231516

18. Mathew-Steiner, SS, Roy, S, Sen, CK. Collagen in wound healing. Bioengineering (Basel). 2021;8(5):63. doi:10.3390/bioengineering8050063

19. Cleveland Clinic. Scars. 2021.

20. National Cancer Institute. Cytokine

21. Mayo Clinic Health System. Are you getting too much protein? 2022.

22. Volpi, E, Nazemi, R, Fujita, S. Muscle tissue changes with aging. Curr Opin Clin Nutr Metab Care. 2004;7(4):405-410. doi:10.1097/01.mco.0000134362.76653.b2

23. Reid-McCann, R.J., Brennan, S.F., McKinley, M.C. et al. The effect of animal versus plant protein on muscle mass, muscle strength, physical performance and sarcopenia in adults: protocol for a systematic review. Syst Rev. 2022;11:64 (2022). https://doi.org/10.1186/s13643-022-01951-2

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