In this article:
- Protein foods list defined for general health and sport performance
- Protein sources for vegans, vegetarians
- Comparing protein source foods
- Best protein sources and amount, and protein sources to limit in diet
What exactly is the definition of protein? Ever wonder why it is so important to athletic fueling and recovery? How much should you be consuming per day? What’s the best source, should you be supplementing with protein alternatives, and how can you be sure you are avoiding protein deficiency?
What is protein?
In elite athlete circles, it is common to hear talk about protein. You often see it advertised on foods in grocery stores and on commercials, but what exactly is it?
Three macronutrients, fat, carbohydrates, and of course, protein, provide you with calories, i.e. energy that you need each day to support your metabolism and activate your muscles. Each macronutrient has its own special role in the body, and protein’s role is essential for building, repairing, and maintaining body tissues like muscles, tendons, bones, and skin. Protein even helps fortify your immune system and assists with hormonal production.3
Every day, your body must replace old, dysfunctional proteins in the body with new, functional proteins. This process, called protein turnover, is the balance between making proteins (synthesis) and breaking proteins down (degradation). To optimize performance, repair, and post-training recovery, you need to ensure that your body has food-derived proteins full of essential amino acids available to build proteins (1).
Amino acids are the building blocks of proteins. Think of a protein as being a candy necklace and each individual piece of candy is an amino acid. After eating and digesting, the necklace is broken and each candy is used in your body to make the specific proteins you need to refuel, repair, and recover. Essential amino acids cannot be made by the body; therefore, we can only obtain them from the foods we eat.
How much protein does an athlete or active adult need?
Many of you have seen various recommendations for protein, most commonly the RDA (recommended dietary allowance), which is 0.8 grams of protein per kilogram of body weight (g/kg). This number refers to the minimum grams of protein needed to achieve a balance of protein synthesis vs. protein breakdown in an average individual.
For health and performance with athletes and active individuals, you should instead consider relying on the ODA (optimal dietary allowance) (1). You may ask, “Why are my needs so much higher?” The reason is… exercise! Exercise sensitizes the muscles to the protein we eat, and you need those important amino acids to support the intensity of the physical work you’re doing. When you use your muscles during training, the aftermath causes anabolic signaling (growth!) which triggers muscle protein synthesis, allowing your body to adapt and have future improvements in function, strength, and performance.
- Get your ODA of protein every day (1).
For general health and weight maintenance (non-athletes) – 1.6 grams/kg
For athletes – 2.0 to 2.4 grams/kg (never exceeding 35% of your total calorie intake)
- Eat protein at all meals and snacks (1). Aim for 20-40g/meal
Where should your protein come from?
You may have heard of caloric density, or foods that have very high caloric values (think peanut butter), or maybe nutrient density (think spinach, which has many vitamins and minerals). However, for protein, you can instead consider essential amino acid (EAA) density (think an egg, which has a high percentage of EAAs). Remember protein synthesis from earlier? Protein synthesis is limited by the EAAs you have available to use from the foods you eat. Also, some amino acids are even more important, like leucine, which triggers muscle protein synthesis.
Animal food sources provide a higher percentage of EAAs and can make it easier to meet your daily EAA needs for improved growth, repair, and recovery. The table below highlights the number of calories and volume required to eat 25 grams of protein from different sources.
Animal proteins are more easily assimilated than plant proteins and more effective at fueling the needs of the muscles. But vegetarians and plant lovers, no need to fear! At higher doses, 30-50 grams of protein, similar muscle gain was seen in a 12-week study comparing plant vs. animal sourced foods (4). Despite a decreased muscle protein synthesis response to plant sourced foods with lower EAAs, the increased protein and sheer number of amino acids available helped the vegan and vegetarian diets achieve similar muscle growth. And for the meat lovers out there, don’t just ignore the plant-based sources of protein. Animal and plant-based proteins contain different levels of different types of amino acids, so eating a combination of plant and animal protein sources can create balance. Animal proteins are high in zinc, iron, vitamin B12, creatine, and essential omega 3 fatty acids. Plant sourced foods are high in fiber, folate, magnesium, vitamin E and antioxidant components (1). Take note that in order to achieve adequate levels of protein solely from plant sources, you may exceed the amount of carbohydrates you require for your activity level.
Did you notice that we have been talking about real, whole foods? Supplementation of protein can have its benefits, but protein from whole food sources should be prioritized. Food is more than just the sum of its components, it’s a complex matrix that we don’t even fully understand. A recent study compared whole eggs to egg whites and measured muscle protein synthesis (5). Both whole eggs and egg whites had the exact same amino acid profile, and whole eggs contained fat that would actually slow digestion and the time it takes for amino acids to reach the muscle. What do you think the result was? The whole eggs created more muscle protein synthesis! It’s not just about the protein or the amino acids, it’s about the food matrix and all the bioactive compounds in real, whole foods (5).
- Eat real, whole foods that are connected to nature. 100% grass fed beef, bison, lamb, wild fish, pastured eggs, and poultry
- Get all your EAAs. Vegetarians, make sure you are favoring amino acids methionine, lysine & leucine4 (sources include oats, seeds, quinoa, buckwheat, lentils, beans)
How can you get optimal protein?
The first thing you can do to guarantee you are meeting your protein requirements is to determine your daily needs based on weight from above. Next, divide that number by the number of meals and snacks you have in a day to give you the average amount of protein you need whenever you eat. Now, how do you determine the amount of protein on your plate?
For quick estimates, use this formula: 1 large egg or 1 oz. of meat, fish, or poultry ≈ 7 grams of protein.
Please reach out to us if you’d like more help on elevating your recovery and repair through protein and diet. With us, you can learn more about specific foods, timing, and straightforward recipes to help you reach your goals.
1. Van Vilet S., Rodriquez N., (2021 October 5. Refeul, Repair, Recover: Can Protein Quality Change the Game? [Webinar]. College and Professional Sports Dietitians Association. https://cpsda.mclms.net/en/package/7450/course/14389/view
2. Cintineo, H. P., Arent, M. A., Antonio, J., & Arent, S. M. (2018). Effects of Protein Supplementation on Performance and Recovery in Resistance and Endurance Training. Frontiers in nutrition, 5, 83. https://doi.org/10.3389/fnut.2018.00083
3. Kleiner, S.M., & Greenwood-Robinson, M. (2019). The New Power Eating. Human Kinetics.
4. van Vliet, S., Burd, N. A., & van Loon, L. J. (2015). The Skeletal Muscle Anabolic Response to Plant- versus Animal-Based Protein Consumption. The Journal of nutrition, 145(9), 1981–1991. https://doi.org/10.3945/jn.114.204305
5. Vliet, S. V., Beals, J. W., Martinez, I. G., Skinner, S. K., & Burd, N. A. (2018). Achieving Optimal Post-Exercise Muscle Protein Remodeling in Physically Active Adults through Whole Food Consumption. Nutrients, 10(2), 224. https://doi.org/10.3390/nu10020224
About the Author
Daniel Dittmer is a SportFuel Intern who recently completed his masters in nutrition from the University of Illinois at Chicago. He is interested in rock climbing and cooking. His favorite meals include skirt steak tacos, grilled shrimp skewers, and crispy skin salmon with chimichurri.
About the Editor
Alex Cotie is SportFuel’s Senior dietitian, who has trained alongside Julie Burns for 10 years. She is dedicated to finding new integrative and individualized methods to help her clients reach their fullest potential. She loves rock climbing, dogs, and spending time outdoors. Alex is currently training for a half marathon. Follow @sportfuelchi on Instagram to hear her weekly updates!