When it comes to your body, protein intake depends on many factors, including your activity level, age, muscle mass, and more. However, there are some general guidelines you can follow.
The DRI is a set of Dietary Reference Intakes set by the National Academy of Sciences (NAS) Food and Nutrition Board. These are composed of four different guidelines RDA (recommended daily allowance), EAR (estimated average requirement), AI (adequate intake), and UL (tolerable upper limit). For protein, the RDA is used to establish general intake goals.
Let's take a look at all things protein, including how much you need, the best sources, and when to eat it.
What is protein?
If you're new to the world of health, food, and fitness, you might be wondering, "What is protein?" Protein is a macronutrient, which means it's one of the three main nutrients that your body needs in large amounts to function properly. Along with carbohydrates and fat, protein plays an important role in your overall health, including energy, muscle growth, repair, and maintenance.
Protein is made up of amino acids, which are the building blocks of muscle tissue. When you eat protein-rich foods, your body breaks down the amino acids and uses them to repair and grow muscle tissue. There are 20 different amino acids, 9 of which are considered essential, meaning your body can't produce them on its own, and you must get them from your diet.
When you exercise, your muscles are broken down and need protein to repair and grow back stronger. That's why protein is often referred to as the "building block of muscle." The more you exercise, the more protein your body needs to support muscle growth and repair. Plus, protein helps you feel fuller after eating, so it can be helpful if you're trying to lose weight or maintain a healthy weight.
Why is protein important for your health?
Protein is an important nutrient for your health. It plays a role in many of your body's functions, including muscle growth, repair, and maintenance. Protein is also necessary for proper immune function, fluid balance, and hormone production.
Protein is responsible for:
- Building and repairing muscle tissue
- Producing enzymes and hormones
- Boosting immune function
- Regulating fluid balance
- Maintaining a healthy weight
Plus, protein is a key nutrient for satiety or the feeling of fullness after eating. This is because protein takes longer to digest than carbohydrates and fat, so it keeps you feeling fuller for longer. This can be helpful if you're trying to lose weight or maintain a healthy weight.
How much protein should you eat in a day?
As a general rule, most people need 0.36 grams of protein per pound of body weight per day. So, if you weigh 150 pounds, you should aim for 54 grams of protein each day. However, there are many factors that can affect your protein needs, including your activity level, age, muscle mass, and more. Let’s take a look at everything to consider when calculating your daily protein intake.
Calculate your protein intake goal
Age and Weight
The recommended dietary allowance (RDA) for protein increases with age. This is because as you age, your muscle mass starts to decline. To help offset this muscle loss, your body needs more protein. The RDA for protein is:
- 0.36 grams per pound of body weight for adults over 18
- 0.45 grams per pound of body weight for adults over 50
While this is the RDA, studies have shown that higher intakes are associated with better bone health, preventing fractures, and higher bone mineral density (2).
There is such a thing as too much of a good thing, so eating too much protein can result in not getting enough of other nutrients, constipation, and other unfavorable side effects.
If you have an active lifestyle, you need more protein than someone who is sedentary. This is because protein helps repair and build muscle tissue. The more muscle tissue you have, the more calories you burn at rest. When working out, your body also breaks down muscle tissue. To help repair this muscle tissue, you need protein. The RDA for protein is:
- 1-1.4 grams of protein per kilogram of body weight- or .45-.64 g/lb of body weight for sedentary to mildly active people
- 1.4-2 grams of protein per kilogram of body weight - or .64-.9 g/ lb of body weight for athletes and highly active people
If you’re pregnant, you need more protein to support the growth of the baby. The RDA for pregnancy is between .88-1.1 g/kg of body weight, while one study found that needs may be closer to 1.2-1.52 g/kg (3).
Ask your doctor specifically for protein recommendations during pregnancy and breastfeeding. You may be surprised to know that nutrition needs are often higher in breastfeeding than they are during pregnancy.
Chronic kidney disease
CKD is one of the rare cases where protein may be slightly limited. This is because your kidneys may not be able to process all the protein you eat. If you have end-stage kidney disease of CKD5 and you're on dialysis, your protein needs may be higher. Ask your doctor or nephrology dietitian how much protein you should eat if you have chronic kidney disease.
Best protein sources
Did you know that you can get all the protein you need from plant-based sources? For years it was thought that you had to combine plant-based proteins in a single meal to form a complete protein. It is now known that the overall amino acid profile throughout the day should be sufficient to create complete proteins when consuming a variety of plant-based sources.
But if you're not vegan or vegetarian, there are plenty of healthy, high-protein foods we typically think of when we say protein to choose from.
Choosing a variety of plant-based and protein sources is a great way to ensure you're getting a variety of different nutrients.
Animal-Based Protein Sources
- Eggs: One large egg has about 6 grams of protein, and they're also a good source of healthy fats, vitamins, and minerals.
- Meat: beef, pork, and lamb are all excellent sources of protein. Choose leaner cuts of meat to reduce your intake of saturated fats.
- Seafood: Fish, shellfish, crustaceans, and mollusks are great sources of protein
- Poultry: Poultry is a lean source of protein that's also low in calories.
- Dairy: Dairy products like milk, cheese, and yogurt are rich in protein and calcium. Choose low-fat or fat-free dairy products most of the time to limit your intake of saturated fat.
Plant-Based Protein Sources
- Beans: Beans are a great source of fiber, protein, and carbohydrates. They can be used in a variety of dishes, from salads to soups to burritos.
- Peas: Peas are a good source of protein, fiber, and vitamins. They can be eaten on their own or added to other dishes.
- Lentils: Lentils are another type of legume that's high in protein and fiber. They can be used in soups, salads, or as a side dish.
- Tofu: Tofu is made from processed soybean that's high in protein and comes in different levels of firmness. It can be used in a variety of dishes, from stir-fries to sauces.
- Tempeh: Tempeh is a type of soybean that's fermented and has a chewy texture. It's often used as a meat substitute in dishes like sandwiches and burgers.
- Edamame: Edamame is immature soybeans that are high in protein. They can be eaten as a snack or added to salads or other dishes.
- Nuts: Nuts are a good source of protein, fiber, and healthy fats. They can be eaten on their own or added to other dishes.
- Seeds: Seeds are a good source of protein, fiber, and healthy fats. They can be eaten on their own or added to other dishes.
Both animal and plant-based proteins are quality protein sources. Consuming a variety is recommended as part of a healthy diet.
Overall consumption is most important, but timing can play a role. Why? Because the timing of your protein intake can influence your level of satiety, muscle growth, protein synthesis, and recovery. When it comes to muscle building and recovery, the timing of your protein intake is important. Research has shown that consuming protein around your workout can have a positive impact on muscle growth, protein synthesis, and recovery.
In fact, eating protein before exercise can help to enhance your workout performance, and eating it afterward, ideally within 30 minutes- 1 hour, can help your muscles to recover and repair.
So, when it comes to protein timing, it’s important to consider when you are working out and how that fits in with your overall daily protein intake. If you are working out first thing in the morning, you may want to consider having a small protein-rich snack before your workout. If you are working out later in the day, you may want to make sure that you are getting enough protein at your meals leading up to your workout.
And after your workout, consume protein within 45 minutes to help jumpstart the muscle-building and repair process. A simple way to do this is to have a protein-rich snack, meal, or shake after your workout.
Again, timing can be helpful with protein intake, especially with high-volume training, but it is a range and something to strive for most of the time—not something to stress about.