Protein is an important part of every diet, especially in increasing or maintaining muscle mass. In general, it’s recommended that most adults get at least 10% to 35% of their daily calories from protein. For men, this may be about 56 grams (g) of protein a day, and for women, this may be about 46 g a day.

There are different protein needs for people who are older, are athletes, have kidney disease, or are pregnant. 

This article will discuss the protein needs for healthy children and adults and the potential effects of a high-protein diet. 

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Daily Recommended Protein Chart 

As with other nutrients, there is a government-recommended amount of protein that people should eat in a day. The Recommended Dietary Allowance (RDA) for protein is considered the baseline for how much protein people should eat in a day. Some people may also need more protein than recommended based on their age, weight, height, and activity level.

The U.S. Department of Agriculture (USDA) publishes guidelines about protein goals. They recommend that most adults try to get between 10% and 35% of their daily calories from protein sources. For a 2,000-calorie diet, this would be between 200 and 700 calories from protein. Another way of looking at it is to aim for about 7 g of protein per 20 pounds of body weight.

The daily recommended intake of protein by sex and age is:

  • Infants: 10 g
  • Children: 19 to 35 g
  • Teenage females: 52 g
  • Teenage males: 76 g
  • Adult females: 46 g
  • Adult males: 56 g
  • Pregnant people: 70 g

The terms male and female are those used in the cited source.

Higher Protein Foods

Some examples of foods that provide about 7 g of protein include:

  • Lean meats, poultry, or seafood: 1 ounce
  • Eggs: 1 egg
  • Cooked beans or tofu: 2 ounces
  • Nut or seed butter: 1 tablespoon
  • Nuts or seeds: 4 ounces

Factors That Influence How Much Protein to Eat Daily

Dietary needs change in pregnancy, and the amount of recommended protein increases. In pregnancy, it may be recommended that people eat at least 60 g of protein a day. This could mean 20% to 25% of daily calories coming from protein sources.

One way of understanding protein needs in pregnancy is to calculate the grams of protein needed per kilogram (kg) of body weight (g/kg). The recommended amount is between 0.88 g/kg and 1.1 g/kg of protein. For example, a 68 kg (150-pound) pregnant person should aim for 60 to 75 g of protein daily.

More physically active people may also need more daily protein. Protein is important for creating and maintaining muscle mass.

One study recommends that activity level be considered in calculating protein needs. The authors of this study recommend people who exercise regularly or are athletes base their protein consumption on activity levels and body weight, as follows:

  • Minimal activity levels: 1.0 g/kg (68 g for 150 pounds)
  • Moderate activity levels: 1.3 g/kg (88 g for 150 pounds)
  • Intense activity levels: 1.6 g/kg (109 g for 150 pounds)

For older adults, it’s important to slow down the loss of muscle mass. One study suggests increased protein levels may help older adults prevent muscle loss and other common health problems. The recommended amount of protein in adults (over age 65) in this study was 1.2 g/kg per day (82 g for 150 pounds).

A higher protein diet may help in losing or maintaining weight. However, after weight loss, some people can’t maintain a high-protein diet for the long term. Weight might be gained back after about a year. The authors of one study advise people changing their diet for weight loss or maintenance take their whole lifestyle into account when choosing an eating plan.

Effects of Too Much Protein

There is not a lot of good data on the health effects of very high-protein diets. Some cultures eat diets higher in protein than others. However, even in these cases, protein is still usually only about 40% of caloric intake.

For healthy people who are not athletes, eating a diet that includes 2 g/kg (136 g for 150 pounds) wasn’t found to have any negative effects. However, eating more than that could lead to some signs and symptoms such as:

Some people who live with chronic kidney disease may be advised to follow a lower-protein diet. One study looked at a diet of less than 0.8 g/kg per day for people with kidney disease. This daily lower protein intake might slow down kidney damage.

People with low kidney function should work with their healthcare team to understand the right balance of protein. The recommendations vary significantly depending on several factors, including whether a person is on dialysis.

A higher-protein diet has not been shown to have a negative effect on the heart. However, increasing plant protein intake was shown to lower the risks of death from heart disease or cancer in one study.

Effects of Too Little Protein

Most people in the United States eat enough protein (including people who follow plant-based diets). However, food insecurity could lead to a lack of protein. Older adults might also be at risk for not getting enough protein because the need increases as people age. 

Some of the signs and symptoms of too little protein include:

  • Increased appetite: A lack of protein may cause some people to have a greater appetite. This could lead to eating excess calories that are less nutritious.
  • Increased risk of infections: A lack of protein could have an effect on the ability of the immune system to fight off infections. People who don’t get enough protein may be more likely to get sick.
  • Increased risk of fractures: Vitamin D, calcium, and protein are important in building healthy bones. People who don’t take in enough protein may be at risk of breaking a bone more easily.
  • Liver disease: A severe complication of a lack of protein is problems with the liver. In adults and children, fat can accumulate in the liver and lead to scarring or poor function.
  • Lack of growth: Protein is important for growth in kids. In children, a lack of protein could lead to growth restrictions.
  • Loss of lean body mass: In adults, a low protein intake could cause a loss of muscle mass.
  • Problems with hair, skin, and nails: A variety of problems with skin and nails can occur due to a lack of protein. Nails may become brittle and not grow well. Hair may be dry, start thinning, and even lose its color. Skin could be flaky, loose, and look prematurely aged.
  • Swelling: The medical term for fluid accumulating in the body is edema. A chronic lack of protein could lead to fluid buildup, which begins in the feet and can extend to other parts of the body over time. 

Sarcopenia

Sarcopenia is a condition that may occur in older people who lose too much muscle mass. It can also happen in younger people, but it is not common. Inactivity and a lack of nutrients can contribute to this problem. Preventing or treating it is important and can include increasing daily protein and calorie intake and an exercise program.

Getting Enough Protein on a Meat-Free Diet

Some people may want to include more protein in their diet from plant-based sources. Focusing on plant protein may mean eating more foods that contain soy (such as tofu), beans, peas, lentils, nuts, seeds, and whole grain products. For those who include dairy and eggs in their eating plan, those are also good sources of protein.

Some examples of plant-based protein sources that contain about 7 g of protein include:

  • 2 ounces cooked beans, peas, or lentils (such as Bayo, black, brown, fava, garbanzo, kidney, lima, mung, navy, pigeon, pink, pinto, or soy, or white beans, or black-eyed peas or split peas, and red, brown, and green lentils)
  • 1 tablespoon of peanut butter
  • 4 ounces of nuts or seeds
  • 2 ounces of tofu
  • 1 ounce cooked tempeh
  • 1 falafel patty (2.5-inch, 4 ounces)
  • 6 tablespoons hummus

How to Up Protein Intake

If you want to increase your daily protein, you can do so in many ways. The first step may be understanding which foods contain protein, especially plant-based sources. The next step may be to eat fewer foods that are low in protein and focus on foods with a higher protein content.

Tracking nutrients in meals throughout the day will also help in understanding how much protein is eaten. Keeping a food log and adding up the amount of protein and total calories can guide hitting protein goals.

Here are some ideas to increase daily protein intake:

  • Focus on adding a protein source to every meal during the day.
  • Consider adding nut butters, which could be eaten with whole grain bread, fruit, or in a smoothie.
  • Add raw nuts to yogurt, salads, or oatmeal.
  • Add protein powder to a smoothie, yogurt, dairy or nondairy milk, or vegetable or fruit juice.
  • Lean jerked meat that is low in additives can make a high-protein snack.
  • Edamame (soybeans) are high in protein and can be eaten alone or with a salad or stir-fry dish.
  • Add tuna, salmon, sardines, or other canned fish to crackers, salads, or a sandwich.
  • Choose whole grains such as quinoa, couscous, or wild rice.
  • Add more protein to breakfast with eggs, cheese, or non-dairy milks.
  • Try roasted chickpeas or dipping vegetables in hummus for a snack.

Summary 

The advice on how much protein people should eat every day varies. A person’s age, weight, and activity level are all important when considering how much protein is needed for overall health. Pregnant people, older adults, and athletes will want to focus on eating more daily protein.

Proteins from animal sources are used more easily by the body, but plant-based proteins may be beneficial in promoting overall health. Eating too much protein or too little over a long period of time could lead to some adverse effects.