For many healthy adults, about 0.8 grams of protein per kilogram of body weight each day is the basic recommended amount, but people who exercise regularly or lift weights may need more to help maintain muscle. Sports-nutrition guidance commonly suggests 1.4–2.0 g/kg daily for exercising adults. The right target depends on activity, age, total food intake, and health, so more protein is not automatically better.
Protein helps your body repair muscle tissue and maintain strength. Getting enough protein becomes particularly important when you exercise regularly, grow older, or try to preserve muscle while losing weight. However, protein is only one part of muscle maintenance. Resistance exercise, enough overall food, and a balanced diet also matter.
How much protein should you eat each day?
The amount you need depends partly on how active you are and what you want to achieve. For a generally healthy, sedentary adult, the recommended dietary allowance is approximately 0.8 grams of protein per kilogram of body weight daily. This is intended to meet the basic needs of most healthy adults, rather than represent an ideal muscle-maintenance target for everyone who trains.
According to Mayo Clinic, people who exercise regularly may need more protein than sedentary adults, with requirements varying according to their activity. People who regularly lift weights or undertake endurance training may benefit from a higher intake than the basic adult recommendation.
The International Society of Sports Nutrition recommends approximately 1.4–2.0 grams of protein per kilogram of body weight per day for most healthy exercising individuals. This range is intended to support muscle building and maintenance in people who exercise. It is not a requirement for every adult, and the most appropriate amount depends on training demands, overall nutrition, and individual circumstances.
How can you calculate your daily protein target?
You can estimate your daily protein intake by multiplying your weight in kilograms by the protein amount appropriate for your activity level. For example, a generally healthy, sedentary adult weighing 70 kg would calculate the basic recommended amount as 70 × 0.8, or 56 grams per day. For an exercising adult of the same weight, the 1.4–2.0 g/kg range corresponds to approximately 98–140 grams daily.
These calculations illustrate how recommendations translate into daily amounts; they are not individualized prescriptions. Someone whose weight is substantially affected by excess body fat may need a different approach to calculating protein requirements. A registered dietitian can help determine an appropriate target based on body composition, physical activity, dietary intake, and health needs.
Does your activity level change how much protein you need?
Muscle tissue is continually broken down and repaired. Physical activity, particularly resistance exercise, stimulates the processes involved in maintaining and developing muscle. Protein supplies amino acids, the building blocks your body uses to repair and maintain that tissue. When training demands increase, adequate protein and overall food intake become more important for supporting recovery and preserving muscle.
People who do little structured exercise may be able to meet their needs with the standard adult recommendation. Those who regularly lift weights, participate in demanding sports, or perform frequent strenuous exercise may need more. However, eating extra protein without an appropriate exercise stimulus does not automatically preserve or increase muscle. Training, food intake, and recovery must work together.
The Centers for Disease Control and Prevention (CDC) recommends that adults include muscle-strengthening activities at least two days per week. These activities can include weight training, resistance-band exercises, or other movements that challenge the major muscle groups. The appropriate exercises and intensity should match your current ability and health.
Is it better to spread protein throughout the day?
Eating protein across several meals is a practical way to reach your daily target without relying on one unusually large serving. You might include a protein-rich food at breakfast, lunch, and dinner, then add a snack when needed. Some sports-nutrition guidance suggests approximately 20–40 grams per meal for many exercising adults, depending on body size, age, and training. This is a general guide rather than a strict limit.
For most people, meeting the overall daily requirement is a more useful starting point than trying to follow an exact eating schedule. Your daily intake does not have to be divided into perfectly equal portions. Choose a pattern that fits your appetite, routine, and dietary needs, and aim to consume adequate protein consistently.
Which foods help you get enough protein?
You can meet your protein needs through a variety of ordinary foods. Animal foods and plant foods can both supply the amino acids needed for muscle maintenance. Including different protein sources also helps you obtain other nutrients that support overall health.
MedlinePlus, a service of the U.S. National Library of Medicine, identifies several sources of dietary protein, including meat, fish, eggs, milk, beans, lentils, nuts, and soy products. Suitable choices depend on your food preferences, budget, allergies, and any dietary restrictions.
Useful options include:
- Dairy products: Milk, yogurt, Greek yogurt, and cottage cheese.
- Eggs and lean meats: Eggs, chicken, turkey, and lean cuts of meat.
- Fish and seafood: Fish, shellfish, and other seafood you enjoy.
- Legumes: Lentils, chickpeas, kidney beans, black beans, and peas.
- Soy foods: Tofu, tempeh, and fortified soy beverages.
- Nuts and seeds: Peanuts, almonds, pumpkin seeds, and other varieties.
A plant-based diet can provide adequate protein when meals include enough protein-rich foods and a suitable variety of sources. You do not need to eat meat or use a supplement to meet your daily needs. Combining different plant foods over the course of the day can help provide the amino acids your body requires.
Are protein shakes necessary to maintain muscle?
Protein powder and ready-to-drink protein shakes can be convenient, especially when your schedule makes it difficult to prepare meals or when your appetite is limited. However, they are not essential for most people. If your regular diet provides enough protein and energy, adding a shake may not offer an additional muscle-maintenance benefit.
Whole foods can provide protein alongside other nutrients, such as vitamins, minerals, fiber, and healthy fats. Before choosing a supplement, check the amount of protein per serving, added sugars, and other ingredients. A supplement should help fill a nutritional gap rather than replace a varied diet.
People with food allergies, dietary restrictions, or medical conditions may need to be more selective about their protein sources. A dietitian can help identify practical options that meet your needs without adding unnecessary products or expense.
How does age affect protein needs for muscle maintenance?
Maintaining muscle becomes increasingly important with age because muscle mass and strength can decline over time. Older adults may benefit from paying closer attention to the amount and distribution of protein in their diet, especially if they eat small meals or have a reduced appetite. Adequate energy intake and regular physical activity are important parts of the same effort.
The National Institute on Aging recommends including protein-rich foods such as seafood, dairy products, fortified soy products, beans, peas, and lentils in meals to help older adults maintain muscle. An older adult's ideal intake can depend on activity, nutritional status, and medical conditions, so the standard adult recommendation should not automatically be treated as the best individual target.
Children and teenagers have different protein requirements because they are growing. Pregnant or breastfeeding people may also have different needs. Adults who are older, undernourished, recovering from an illness, or experiencing unintended weight or muscle loss may benefit from individualized dietary advice rather than relying on a general formula alone.
What else helps prevent muscle loss?
Protein cannot replace the other factors needed to preserve muscle. Regular resistance exercise gives muscles a reason to remain strong, while adequate total food intake supplies energy for daily activity and recovery. If you regularly eat too little, especially during intentional weight loss, it may be harder to maintain lean body mass even when you pay attention to protein.
To support muscle maintenance, build your routine around a few practical habits:
- Include strength-building activities that suit your ability and experience.
- Eat enough total food to support your daily activity and nutritional needs.
- Include a protein-rich food in regular meals and snacks when appropriate.
- Allow time for recovery between demanding exercise sessions.
- Avoid extreme or unnecessarily restrictive diets that make it difficult to meet nutritional needs.
If you are losing muscle or strength without intending to, have difficulty eating enough, or notice a persistent decline in physical function, discuss it with a healthcare professional. These changes can have several possible explanations, and increasing protein alone may not address the underlying issue.
When should you seek advice about protein intake?
Most healthy adults can obtain enough protein from a balanced diet. However, some medical conditions change how the body handles protein or require particular dietary limits. For example, people with chronic kidney disease may need an individualized protein plan depending on their kidney function, nutritional status, and treatment. A high-protein diet should not be assumed to be suitable for everyone.
Seek guidance from your healthcare professional or a registered dietitian if you have kidney disease or another condition that affects your diet, are recovering from a major illness, follow a highly restrictive eating pattern, or are concerned about unexplained weight or muscle loss. They can help you determine an appropriate daily target and whether your current meals provide enough protein and energy.