The Importance of Amino Acids With Protein Deficiency


Verywell / Alexandra Shytsman

We live in a society where eating protein for weight loss, bodybuilding, and health is highly marketed and abundant. Consuming meats, fish, and plant foods can easily supply your daily requirements. Many active adults and athletes believe more is better and further supplement by drinking protein shakes and eating nutrient-filled bars.

With protein everywhere and in almost everything, it’s hard to believe protein deficiency would be a concern. In fact, there continues to be a false prevailing notion that getting enough protein is difficult, according to David. L. Katz, MD, MPH, FACPM, FACP, Founder, and Director of the True Health Initiative.

Maybe it’s just a matter of understanding the meaning of protein deficiency.

What Is Protein Deficiency?

Genuine protein deficiency is effectively non-existent in the United States and other developed countries, says Dr. Katz. It does exist in underdeveloped countries, especially in Africa and Asia.

Protein deficiency is also known as protein-energy malnutrition (PEM). When PEM is caused primarily by protein malnutrition, it’s called kwashiorkor. When significant protein deficiency is coupled with marked caloric restriction, it’s referred to as marasmic kwashiorkor, the most extreme form of malnutrition.

One of the adverse effects of kwashiorkor is edema or fluid buildup in the tissues. The bloated belly seen on severely malnourished children in famished countries is characteristic of kwashiorkor.

There are a few rare cases of true protein deficiency in the United States. Hospitalized patients who are gravely ill make up the majority. A very small percentage of the elderly, and individuals following extremely restrictive diets not realizing they were causing a severe nutrient deficiency.

Since America is far from starving, true protein deficiency is almost impossible. However, not getting enough protein in your diet can become a problem over time. When protein deficiency is marginal it can start having a negative impact on your health.

This is why adequate protein intake is essential for you to maintain proper body function. Going a step further, understanding the role of protein and taking personal responsibility for adequate intake is important.

Protein and Amino Acids

Protein is a macronutrient that works within every cell of your body. It is required for muscle development and regulating body tissues and organs. It’s made from a chain of amino acids considered the building blocks of protein. There are 20 total amino acids comprised of nine essential amino acids and 11 non-essential amino acids.

According to Caroline Passerrello, MS, RDN, LDN, Spokesperson for the Academy of Nutrition and Dietetics, there are nine essential amino acids that we must consume in order to meet protein requirements because we cannot make them within the body. Protein in muscles and body tissue is in constant turnover, therefore, protein is required daily to maintain a steady state in the body.

Low Dietary Protein and Requirements

According to a study published in the Annals of the New York Academy of Sciences, approximately one billion people worldwide have inadequate protein intake. This would mean we are eating less protein than your body needs, according to nutrition expert Caroline Passerrello. Since your body requires a sufficient amount of protein, not consuming enough can potentially lead to poor health.

The recommendation is approximately 10-20 percent of your total calories come from protein or about .8-1g of protein per kg of body weight each day. For example, a person weighing 150 pounds who needs 1800 calories per day would intake 55-68 grams of protein daily to meet a 15 percent daily protein requirement, says Passerrello.


Protein deficiency can occur when you’re not eating enough protein to maintain normal body function. Approximately one-third of adults over age 50 are failing to meet the recommended daily allowance (RDA) for protein intake according to research.

Individuals following a restrictive diet can also be at risk of becoming protein deficient. Some athletes in weight class sports like boxing, wrestling, and bodybuilding may use self-starvation methods to lean up leaving them nutrient deficient.

When protein is lacking in your diet, especially for long periods of time, it can cause you to be deficient and potentially lead to adverse effects. Caroline Passerrello, MS, RDN, LDN, indicates inadequate protein can lead to the following:

  • Muscle Wasting – Protein is essential for muscle growth, strength, and repair. Insufficient protein in your diet reduces lean body mass, muscle strength, and function. Not consuming enough protein can also cause muscle cramping, weakness, and soreness. Your body will take protein from muscle tissue and use it as energy to support other vital body functions when protein is low. This eventually causes muscle wasting or atrophy as a direct result of chronic, low dietary protein.
  • Poor Wound Healing – Wound healing is dependent on good nutrition, including protein intake. Protein deficiency has shown to contribute to low wound healing rates and reduced collagen formation, according to research. Without adequate protein, the wound healing process is said to be greatly compromised.
  • Infections – Your immune system functions best with adequate protein intake. Protein deficiency is indicated to impair your immune system. Without a healthy immune system, your risk of infection is increased and the ability to fight off infection is decreased. 

How Can I Include More Protein?

In order to maintain a healthy body, adequate protein intake is essential. This doesn’t mean more is better, nor does it mean eating extra protein can only build muscle, not body fat, according to Dr. Katz.

What is recommended is eating enough protein to support your body cells, structure, and function. This requirement will be different for each person.

There are instances where low dietary protein may be a concern. This is especially true for some elderly and for those restricting their diet too much. In these instances, protein intake is easily increased and a simple process.

Protein is included in a wide variety of animal and plant foods. Choosing nutritious protein sources is also recommended for optimal health and fitness. Nutrition expert, Caroline Passerrello recommends the following:

  • Aim for meals to have approximately 20 grams and snacks to have about 10 grams of protein (3 ounces of cooked chicken breast has about 21 grams of protein).
  • Eat higher protein grains like quinoa.
  • Select bean-based noodles instead of wheat-based pasta.

6 Tips for Getting More Protein in Your Diet

Plant-Based Diet

Eating plant-based is a popular trend. Several studies have indicated plant-based diets provide numerous health benefits. One of the most common myths of vegetarian or plant-based eating is that you’re unable to get enough protein in your diet.

Another myth claims you have to pair plant proteins to get all the amino acids to make a complete protein. Current research indicates you can get enough protein when eating a variety of plant foods over the course of the day and combining is not necessary.

According to the Academy of Nutrition and Dietetics, plant-based or vegetarian diets can be nutritionally sound and adequate for all individuals, including athletes. The following is a great list of plant-based protein sources to include in your diet:

  • Lentils
  • Quinoa
  • Tofu
  • Black beans
  • Pumpkin seeds
  • Almonds
  • Oats

Other Protein Selection Tips

According to the United States Department of Agriculture (USDA), protein intake depends on age, gender, and physical activity level. They also suggest that most Americans eat enough protein but need to make leaner and more varied selections of these foods.

The following protein selection tips from the USDA will be helpful:

  • Choose lean or low-fat meat and poultry.
  • Select seafood high in omega 3 fatty acids including salmon, trout, sardines, and anchovies.
  • Avoid fresh chicken, turkey, and pork that have been enhanced with a salt-containing solution.
  • Choose unsalted nuts and seeds to keep sodium intake low.

In general, 1 ounce of meat, poultry or fish, ¼ cup cooked beans, 1 egg, 1 tablespoon of peanut butter, or ½ ounce of nuts or seeds can be considered as 1 ounce-equivalent from the Protein Foods Group.

A Word From Verywell

True protein deficiency is rare in the United States but exists for some at marginal levels. Protein is essential for all cells and body tissue and when in short supply can impair body function.

Adding protein to your diet is a simple process and achieved by incorporating a wide variety of foods from either plant or animal sources. Recommended protein requirements vary per person depending on age, gender, and physical activity levels. Getting enough protein can be achieved by eating a plant-based (vegan) diet or diet that includes both plant and animal protein sources. 

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Article Sources
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