From the Guidelines
Low protein levels in the blood, known as hypoproteinemia, can be caused by several factors, including poor dietary intake of protein, malabsorption disorders, liver disease, kidney disease, severe burns or skin conditions, and chronic inflammatory conditions. The most common causes of low protein levels include:
- Poor dietary intake of protein
- Malabsorption disorders like celiac disease or inflammatory bowel disease
- Liver disease that impairs protein synthesis
- Kidney disease that leads to protein loss in urine (proteinuria)
- Severe burns or skin conditions that cause protein loss
- Chronic inflammatory conditions Malnutrition, whether from inadequate food intake or eating disorders, directly reduces available protein 1. Digestive issues prevent proper absorption of dietary protein. Liver dysfunction impairs albumin production, the main blood protein. Kidney problems allow proteins to leak into urine instead of remaining in blood. Additionally, conditions like sepsis, major surgery, or cancer can increase protein requirements or cause protein breakdown. Reducing the amount of dietary protein below the recommended daily allowance of 0.8 g/kg is not recommended because it does not alter glycemic measures, cardiovascular risk measures, or the rate at which glomerular filtration rate declines and may increase risk for malnutrition 1. Treatment depends on identifying and addressing the underlying cause, which may include dietary changes, medication adjustments, or specific therapies for the primary condition. Maintaining adequate protein levels is essential for proper immune function, fluid balance, and overall health. According to the most recent study 1, there is no evidence that adjusting the daily level of protein intake will improve health, and research is inconclusive regarding the ideal amount of dietary protein to optimize either glycemic management or CVD risk. However, strong evidence suggests higher plant protein intake and replacement of animal protein with plant protein is associated with lower risk of all-cause and cardiovascular mortality 1.
From the Research
Causes of Low Protein Levels
- Decreased dietary intake is a principal cause of protein deficiency, often associated with liver disease 2
- Deficiencies in digestion and absorption, common in alcoholics, contribute to protein deficiency in alcoholic liver disease 2
- Dietary protein insufficiency has been linked to excessive TAG storage and non-alcoholic fatty liver disease (NAFLD) in developing countries 3
- High levels of animal protein intake may significantly increase the risk of premature mortality from all causes, including cardiovascular diseases, cancer, and type 2 diabetes 4
- Protein-energy wasting, a syndrome characterized by loss of lean body mass and underutilization of fat mass, is common in patients on dialysis with low serum albumin levels 5
Related Factors
- Vitamin deficiencies, common in liver disease, contribute to abnormalities of protein metabolism 2
- Hepatic regeneration following hepatic resection or injury is adversely affected by protein and vitamin deficiencies and by alcohol ingestion 2
- Inflammation drives losses of body protein and fuel reserves, making correction of the underlying inflammatory disorder crucial for addressing protein-energy wasting 5
- High-protein intake may lead to increased intraglomerular pressure and glomerular hyperfiltration, causing damage to glomerular structure and leading to or aggravating chronic kidney disease (CKD) 6