Approximately 16 % of the human body is made of protein. Without protein, our bodies would be unable to heal from injury, stop bleeding or fight infection. That‘s why eating protein is so important in order to stay healthy.
Proteins consist of the amino acids.Your body needs the right amount of protein and amino acids, respectively, with your diet, because they are used for the:
- Repair of tissue
- Building of hormones
- Building of antibodies and enzymes
- Help of balance acid/base, fluid and electrolytes
- Provision of some of the body's energy
Calories / Energy
The intake of a sufficient amount of energy is very important for your health and well-being. Eating insufficient calories will lead to the breakdown of body protein (especially muscles) – this means that you will feel weak and will lose weight.
Your need for energy depends on your age and physical activity. In general, your dietary energy intake should be:1
- 35 kcal/kg body weight/day if you are younger than 60 years
- at least 30 kcal/kg body weight/day if you are 60 years or older
This applies to patients with chronic kidney disease in the predialysis stage as well as to patients on dialysis.
Next to calcium, phosphate is the second abundant essential mineral in your body. Phosphate is found in every cell of your body, but more than 80 % are present in your bones and teeth.
Phosphate is an important element for many essential processes in your body:
- Formation of bones and teeth
- Utilization of fat, carbohydrate and protein for maintenance, growth and repair of cells
- Energy production
- Utilization of many B-vitamins
Calcium is the most abundant mineral in your body. Almost all of your calcium is found within the bones and teeth, where it is responsible for their strength and stability. Beside this, a small quantity of calcium is always in your bloodstream and has many important functions:
- Formation of bones and teeth
- Coagulation of blood
- Contraction of muscles (including your heart)
- Transfer of chemical messages from the cell membrane into the cell
Sodium is an essential mineral. In your body, sodium is the most predominant ion in your extracellular fluid and is subject to a tight regulation. Sodium consort with potassium (the main cation within the cells) to maintain a proper body water distribution and blood pressure. This means, the body needs a small amount of sodium:
- To regulate blood volume and blood pressure
- To regulate acid/base balance
- To maintain a normal function of muscles and nerves
Potassium is the third most abundant mineral in your body. Potassium is mainly located within the cells and is considered as the ionic counterpart to sodium and chloride. A proper balance between these minerals is necessary for many body functions. Potassium is essential for the proper function of all cells, tissues, and organs – including your heart.
Potassium is involved in:
- Muscle contraction
- Maintaining the electrolyte and fluid balance within the cells
- Conduct nerve impulses
When your kidney function slows down, your kidneys will produce less urine. The less urine your kidneys make, the less fluid you can drink. The daily amount of fluid you are allowed to drink depends on the amount of urine you produce.
Fluid intake in predialysis2
In early stages of your disease (stage 1-4), you do not need to limit your fluid intake as long as your urine output is normal.
As your kidneys become worse (stage 5) and you recognise a swelling of your ankles and feet or weight gain, you have to restrict your fluid intake.
- D'Alessandro C, Piccoli GB et al. "Dietaly": practical issues for the nutritional management of CKD patients in Italy. BMC Nephrol 2016; 17(1): 10
- Cano NJ, Fiaccadori E et al. ESPEN Guidelines on Enteral Nutrition: Adult Renal Failure. Clin Nutr 2006; 25(2): 295–310