How Common Is Protein Deficiency?

A lamb lettuce salad topped with eggs and nuts.
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Protein deficiency is pretty rare in healthy adults, according to the Centers for Disease Control and Prevention, or CDC. In fact, it states most Americans consume more protein than their body needs. It can be unhealthy to consume too much or too little protein. Protein deficiency is most prevalent in vegetarians or in those who don't consume enough calories to satisfy the body's nutritional needs. By monitoring your daily intake of protein, you can be sure you're getting enough of the nutrient.

The CDC says adult women and men should consume about 46 g and 56 g of protein per day, respectively. Physically active adults may need more than this amount. In the American diet, it's tough not to reach this amount of protein over the course of a day. For example, you can get over 50 g of protein by eating two eggs for breakfast, a turkey and cheese sandwich for lunch and a 3-oz. portion of meat with veggies at dinner.


Vegetarians and Vegans

Vegetarians and vegans may be at an increased risk of consuming too little protein. This is because most sources of complete proteins – protein that contains all of the essential amino acids you need – are eliminated from a vegetarian or vegan diet. This could include meat, cheese, dairy and eggs. However, vegetarians and vegans can consume soy protein, which is the only plant-based source of complete proteins. Soy protein is used in a variety of vegetarian foods, such as tofu and soy milk.


Diets that are not well-planned out can put you at risk of becoming protein deficient. Although protein deficiency as a whole is extremely rare in the U.S., the University of California Los Angeles states that people on a weight-loss plan may exclude protein from their diets to avoid the calories and fat. This can lead to loss of muscle, called atrophy, and other potential health problems. You should never start a diet plan without first consulting your doctor or dietitian.



When you don't eat enough protein, your body begins breaking down muscle and other tissue to get the amino acids it needs. Additionally, you may notice symptoms of lowered immune system function, so you can get sick much easier. It also can affect injury and wound healing, as protein plays a major role in this bodily function. Protein also helps promote satiety, or a feeling of being full, and lack of the nutrient may cause you to crave foods high in carbohydrates and sugar. Overall, protein-deficient individuals have low energy levels, poor immunity and unhealthy body composition. It's a potentially deadly situation that must be addressed immediately by visiting your doctor.