The kidneys play a very important role in regulating water and nutrients in the body. One of the primary functions of the kidney is to filter water and waste from the blood. When the kidneys are damaged, their ability to protect the body is compromised. Most people who suffer from kidney damage rely on dialysis to replace the filtration function of the kidneys. Because dialysis cannot fully compensate for the loss in kidney function, patients are required to adopt a stricter diet plan than what they are used to.
All dialysis facilities employ renal dietitians whose job it is to help patients develop a diet plan that will prevent excess fluid and waste buildup between treatments. Dietitians understand that patients prefer to enjoy their meals and they work very hard to make sure that the diet plan includes renal diet recipes that the patient can enjoy. Since meal time often involves the entire family, the dietitian will take time to discuss with the patient’s family the importance of the diet plan and the actions that can be taken to help the patient remain compliant. It is often important for family members to encourage patients to stick to the diet and not be persuaded to eat foods that might compromise the effectiveness of the dialysis treatment.
The Importance of Diet and Nutrition
The reason that nutrition is so important in dialysis therapy is because the wastes that accumulate in the body are mostly by-products of the metabolic process that occurs when we digest food. Healthy kidneys are capable of filtering excess particles such as urea, creatinine, potassium, sodium, phosphorous, and water from the blood. While our bodies do depend on these particles for survival, excess accumulations often cause damage to vital organ systems. Dialysis patients tend to accumulate waste particles in their bodies between treatment sessions. This occurs because they do not have a filtration mechanism that is constantly working to remove wastes from the blood. Nutrition and renal diet recipes are one of the most important methods for controlling the amount of waste that is allowed to accumulate.
Primary Food Groups
Renal dietitians often focus on a few key food groups when helping patients develop a plan for their overall nutrition and the renal diet recipes that they will consume. These food groups include protein, dairy, bread/starches, fruits and vegetables, fats, and compact sources of calories. Protein can be found in most foods, but the type of food will determine how valuable a source of protein is. Dietitians use the term high biological value to describe protein that is found in meat, fish, chicken, soy, and dairy products. Sources of low biological value protein include bread, grains, vegetables, beans, and fruits. The process of dialysis usually removes more protein from the body than would normally be filtered by a healthy pair of kidneys. For this reason, dialysis patients usually need to incorporate renal diet recipes that contain 50% more protein than is found in a normal diet. Dialysis facilities will monitor the BUN and creatinine in a patient’s blood in order to assess the level of protein in the body.
While protein is a critical component of the renal diet, it is not the only nutrient that patients need to keep track of. Particles that are common such as sodium, potassium, calcium, phosphorous, and vitamins all play an important role in maintaining a healthy nutritional balance. Sodium is one major component of salt and can be found in just about every type of food available. One of the most important roles of sodium in the body is to regulate fluid balance within the blood vessels and body compartments.
In general, water will cross membranes if there is a high concentration of sodium on the opposite side. In dialysis patients, high levels of sodium often lead to fluid retention which causes high blood pressure, swelling, and fluid weight gain. In order to avoid these unpleasant symptoms, dialysis patients must restrict their sodium intake to less than 1,500 mg per day. This means that most renal diet recipes cannot contain sodium-rich foods such as canned foods, pickled foods, cold cuts, sausages, or hot dogs. Dialysis patients should also be careful to avoid spices and seasonings.
Potassium can be an especially troublesome nutrient because it is contained in many types of commonly consumed foods such as avocados, mangos, bananas, oranges, dried fruit, melons, orange juice, beans, potatoes, and coffees. Like other particles, excess potassium can accumulate in the body between dialysis treatments if patients are not extremely careful about the foods they consume. The reason that potassium is so important is because it functions to maintain the electrical charge that exists inside and outside of cells. One of the most profound examples of this physiological mechanism is the electrical charge that allows the heart to continue beating. If too much potassium builds up in the body it can cause the heart to stop beating and may result in sudden death. Individuals who are suffering from dangerously high levels of potassium in the body may experience muscle weakness, trouble walking, abnormal heart rhythms, and cardiac arrest. Strict renal diet recipes often exclude salt substitutes and foods that are labeled ‘low salt’ because they often contain high concentrations of potassium.
Calcium and Phosphorous
Calcium and phosphorous are important nutritional elements because of their role in bone formation and metabolism. A healthy pair of kidneys not only filters waste from the blood but also transforms Vitamin D to its active form so that calcium and phosphorous can be kept in balance. Since dialysis patients do not have a system that can transform Vitamin D to its active form, they must remain diligent in restricting their calcium and phosphorous intake. This can be a challenge because these nutrients are found in many foods including dairy, chocolate, pizza, soda, beans, grains, and nuts. Healthy renal diet recipes do not include large amounts of these food items. Patients should also make sure that they are avoiding foods that contain phosphate and phosphoric acid. Another method for reducing the affects of excess calcium and phosphorous is to take medications that bind these nutrients in the digestive tract.
Vitamins and Calories
There are many restrictions that are placed on dialysis patients when it comes to nutrition and renal diet recipes. Individuals who have healthy kidneys are not generally concerned about the type and amount of food that they consume because they have a system that will filter excess water and waste from the body without them even thinking about it. While there are many challenging dietary changes that must be adopted when managing kidney failure, there are also many common sense practices that everyone can benefit from regardless of the status of their kidneys.
Like individuals with health kidneys, dialysis patients need to supplement their diets with a combination of different Vitamins including A, B, C, D, E, and K. The process of dialysis treatment can remove these vitamins from the body and they need to be restored through supplementation. Also like healthy individuals, dialysis patients must make sure that they are consuming enough calories to maintain a healthy body weight and avoid the negative consequences of malnutrition.
The final important aspect of nutrition and renal diet recipes involves proper fluid consumption. Unlike healthy individuals, dialysis patients are often unable to produce urine and are entirely dependent on dialysis to remove excess fluid from the body. In general, the dialysis treatment team will attempt to assess how much fluid must be removed at treatment sessions based on the amount of fluid consumption that occurred between sessions and whether or not the patient is able to produce any urine.
Patients who produce little or no urine are often restricted to four cups of fluid or less each day. When calculating overall fluid consumption, it is important to remember that things like Jello, ice cream, and popsicles are considered fluid because they are liquid at room temperature. Removing the appropriate amount of fluid can be a challenging process that can result in some very uncomfortable side effects when not performed properly. For this reason, it is important for dialysis patients to keep track of their fluid consumption and adhere to the nutrition guidelines and renal diet recipes that have been provided by the dietitian. Understanding your fluid restrictions and honestly communicating your level of compliance to dialysis personnel can go a long way in ensuring the most positive health outcomes possible.
Renal Diet Recipe Resources:
- Hemodialysis Technician
- Kidney Detox