When protein is used by the body it creates a number of wasted products which are usually filtered and removed in the kidneys by an intricate system of nephrons. In the presence of any type of kidney disease, usually chronic kidney disease, these waste products are not filtered out and will back up and increase in numbers, eventually ending up back in the blood system. Chronic kidney disease is based on five stages of progression, typically judged by the glomerular filtration rate, which is a rating of how much blood the kidney can filter.
A healthy kidney filters roughly eighteen gallons of blood per hour and over half of the body’s fluid. The kidneys can create and excrete up to two quarts of urine every day. (Source: MacLean, 1993) Because protein is vital to good health, it cannot be eliminated entirely from the diet, however in the third and fourth stages of chronic kidney disease, the amount of protein will be greatly lowered (it will increase again in the fifth and final stage).
The glomerular filtration rate is a necessary testing that can be used to gauge the seriousness of the kidney disease, however new findings are suggesting that another test may be needed to predict the outcomes from the disease and may be more indicative of actual prognosis than the GFR is.
Proteinuria is the medical term for excessive protein in the urine and is common in a number of diseases, especially those that are related to the kidneys. A new study is showing that those who have baseline proteinuria are at increased risk for death, regardless of their glomeralur filtration rate. In the study of over one million people, the death rate was doubled with heavy proteinuria,.
Proteinuria increased the three year risk of death from heart attack and/or kidney failure. Heart attack risk went up by 50% while end stage renal disease and doubled levels of serum creatinine were up to 30% more common. Patients who had heavy proteinuria but fairly decent glomerular filtration rates had more negative outcomes than those who had worse GFR but no protein in their urine. (Source: Gever, 2010)
Protein Restrictions for the First Four Stages of Chronic Kidney Disease
For most people, protein intake of around .5 to .8 grams per kilogram is plenty. The exception to this need is those who are very active or who are recovering from burns, trauma, surgery, or certain types of illness. The average person gets about 15-20% of their calories from protein sources. In the first three stages of chronic kidney disease that number will be only slightly reduced at 12-15%. (Source: Davita.com) This amount of protein is consistent with that of the vegan diet which is around 10-12% protein. (Source: Mangels, PhD, RD)
The fourth stage, which is the last stage before the need for dialysis begins, the protein restriction is a little more severe with only ten percent of the overall daily calories coming from protein.
Stage Five CKD and the End of the Protein Restriction
While the first four stages of chronic kidney disease are marked by protein restrictions, there is a definite need to increase protein intake in stage five, after dialysis begins. The kidneys at this stage are typically only working to about ten percent of their capacity so a machine takes over the role of filtering the blood to remove the waste products from it. However, dialysis does more than take out the waste products, it also removes amino acids. The body needs amino acids for a number of functions in the body- from sleep to digestion and even our mood. At this stage the increased protein will make up for the lost amino acids and will prevent muscle loss. It also works to fight infection.
How Vegetarian Protein May Help Slow CKD Progression
Protein comes from two sources, from animals and from plants. Vegetarian protein may help the body to get the right amount of protein with less protein waste product build up, slowing the progression of chronic kidney disease. While soy is the only complete vegetable protein (it contains all of the essential amino acids that the body cannot create on its own) others can help to provide good nutrition and to help maintain the balance of sodium, potassium, and phosphorous in the body. (Source: Brookshyer RD, CSR)
It is important to eat a variety of plant based proteins, especially if you are following a vegan diet so that each of the missing amino acids can be made up for. Grains, nuts, and seeds are typically low in the amino acids isoleucine and lysine while legumes are low in tryptophan and methionine. (Source: Best)
Why Protein Supplements Can Be Beneficial
Not only is it important to get the right amount of protein in the diet to maintain the remaining kidney function and to keep the strength up for as long as possible, it is also necessary to make sure that the right kind of protein is being used. There are a number of additional nutrients that will need to be monitored in the diet, including phosphorous which can build up in the system and become toxic, particularly to the bones. Foods that are high in phosphorous include: milk, yogurt, cheese, dried beans, peas, nuts, and seeds. Salmon, sardines, and halibut are also high in phosphorous.
If you choose to use protein supplements, make sure that you read the ingredients carefully and now how they are derived. All protein supplements come from the same two sources of protein, animals or plants. There are some that are listed as vegetarian or vegan while others make no such claim. Regardless, it is important to note exactly what each supplement is made of and how the protein is derived. Remember also that some proteins can be very difficult to break down in the body and may not be as easily assimilated as others. Proteins make up the most common micro allergen group as well, so use great caution when adding a new product to your diet especially during periods of compromised health status.
Profect and Proasis from Protica are both protein supplements to consider. Both have more high quality protein per serving than any other supplement of its kind and can be used in a number of ways. Proasis is the first, all natural protein supplement and is preservative, lactose, fat, and stimulant free. It is hypoallergenic and is made without egg, yeast, wheat, or gluten and is also aspartame free.
Both Proasis and Profect are available in a number of fruit based flavors for palatability. Both are also available in a number of convenient sizes for each individual’s nutritional needs.