High urine protein, also called proteinuria, is a red flag for chronic kidney disease. Often this goes on for years, until picked up during a routine physical or life insurance exam. In some instances, it can be controlled by diet. However, before you swear off meat and high protein foods, consult your nephrologist to see if dietary changes are really needed.
The glomeruli, or filters of healthy kidneys, clean over 200 gallons of blood a day. Waste products from muscular activity, such as creatinine and urea, are removed from the blood and filtered into the urine. Proteins, however, remain in the blood. Inflamed kidneys are less able to perform this function. For reasons that remain unclear, proteins pass through the inflamed glomeruli into the urine.
Nephrologists try to control severe proteinuria because it can damage the kidneys independently from any underlying disease and accelerate the progression of kidney disease. Most people consume far more protein than they actually need. The National Kidney Foundation guidelines suggest that patients with stage 1 through stage 4 kidney disease limit their daily protein intake to 0.8 g per kilogram body weight. This is identical to the protein requirement set by the U.S. Department of Agriculture.
Recommended Protein Intake
The National Kidney Foundation guideline means that a 120 lb. person should consume 44 g of protein per day. A 140 lb. person should consume 51 g of protein per day. A 160 lb. person needs 58 g of protein. Protein can easily creep into your diet without you being aware of it. For example, two slices of wheat bread have 5.46 g of protein.
Nephrologists do not recommend low protein diets for everyone. For example, they are never recommended for children, patients on hemodialysis or patients approaching transplant. Moreover, newly diagnosed patients are often so enthusiastic about dietary changes, they often take matters to extremes and do not get enough protein. Before embarking on a low-protein diet, consult your nephrologist about how much protein you should consume.
- National Kidney Foundation: How Your Kidneys Work
- National Kidney Foundation: NKF KDOQI Guidelines
- USDA: Bread, Wheat
- National Institute for Diabetes and Digestive and Kidney Diseases: Proteinuria
- USDA; Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids - Chapter 10; 2005