Protein deficiency occurs when the body does not receive enough protein, which is uncommon in developed countries like the United States, where food is readily available.
However, certain groups are more vulnerable, including the elderly, children who have faced neglect or abuse, and individuals with health conditions that hinder protein absorption or metabolism.
Read Also: 6 Signs Showing You Could Be Eating Too Much Protein
Protein plays a critical role in many bodily functions, such as the formation of muscles, bones, skin, hair, and nails.
It also aids in immune system function and brain activity.
As a result, a lack of protein can lead to a variety of symptoms like brittle hair and nails, mood swings, muscle weakness, and a higher frequency of illness.
- Weakness and Fatigue
Protein is a key energy source. Deficiency can lead to both mental and physical fatigue, impacting a person’s quality of life and physical abilities. In severe cases, such as prolonged fasting or starvation, muscle wasting (cachexia) may occur, which is also linked to health issues like heart failure, kidney disease, COPD, cancer, and AIDS. - Skin, Hair, and Nail Issues
Protein deficiency often manifests through dry, thinning hair and brittle nails. In more extreme cases, hair may lose its color or curly hair might straighten. Skin may become fragile, peeling, and flaky. Individuals with eating disorders like anorexia or bulimia may develop soft, fine hair on their face and body. - Mood Changes
Amino acids from protein are essential for producing neurotransmitters like serotonin and norepinephrine, which regulate mood. A lack of protein can lower these neurotransmitters, leading to mood disorders such as depression. Symptoms of depression include persistent sadness, irritability, loss of interest in activities, changes in appetite or sleep, hopelessness, and difficulty concentrating. Anxiety, particularly in teenagers, has also been linked to protein deficiency. - Swelling
Swelling, especially in the feet, ankles, and abdomen, is a significant symptom of kwashiorkor, a severe protein deficiency. This condition, often seen in children in areas with limited food, results from low albumin levels, which cause fluid to leak from blood vessels. Additional symptoms of kwashiorkor include stunted growth, thinning hair, dry skin, and lack of energy. Swelling can also occur in conditions like nephrotic syndrome, a kidney disease that leads to significant protein loss through urine. - Reduced Immunity
A lack of protein weakens the immune system, making the body more vulnerable to infections such as urinary tract infections, pneumonia, ear infections, and gastroenteritis. This happens because the body struggles to produce antibodies and cytokines, essential for immune function and healing wounds. - Bone Health
Low protein intake can worsen the natural decline in bone mineral density (BMD), which is crucial for bone strength. A decrease in BMD increases the risk of osteoporosis, where bones become brittle and more prone to fractures. Other factors that contribute to osteoporosis include low calcium and vitamin D intake, hormonal changes, and inactivity. - Stunted Growth in Children
Children who do not get enough protein may experience stunted growth, which is when their height is below the 2.5th percentile for their age. This is often seen in children with kwashiorkor or marasmus, a severe protein and calorie deficiency. Children with marasmus experience extreme weight loss, muscle wasting, and a very thin appearance. Insufficient protein during childhood disrupts the metabolic processes needed for proper development, leading to stunted growth. - Fatty Liver
Fatty liver occurs when triglycerides build up in liver cells. While obesity and alcohol consumption are common causes, protein deficiency can also play a role. This happens when the liver cannot produce enough proteins to move triglycerides out of the liver. Although the symptoms are usually mild or nonexistent, fatty liver may cause discomfort in the stomach or fatigue. - Weight Fluctuations
In response to severe protein deficiency, the body reduces its metabolic rate and breaks down fat for energy. If fat stores are depleted, the body starts breaking down muscle and organ tissues, leading to significant weight loss. In cases of starvation, where both protein and other nutrients are lacking, weight loss may exceed 50%. Protein deficiency can also lead to weight gain, particularly in conditions like nephrotic syndrome, due to fluid retention. Some studies suggest that individuals on lower-protein diets may experience increased hunger, contributing to weight gain.
