Protein & dialysis: the basics
Protein -- the building material for your body
Proteins are the building materials of our body. An optimal protein intake is important in order not to deplete your body's reserves. Among other things, we need them to build and maintain muscles, for immune defense and as a component of the blood. Protein is found in animal and plant foods.
Because protein is lost during dialysis, the recommended daily protein intake for dialysis patients is increased by about 40% compared to people not on dialysis. Especially if you dialyze through your peritoneum (=peritoneal dialysis or PD), the blood cleansing process washes out a lot of the proteins. In order to still get enough protein, you need to increase the amount of protein in your daily diet.
What exactly are proteins?
Proteins consist of several building blocks, the so-called amino acids. You can think of them as Lego bricks. Our body cannot produce some of the building blocks itself. Therefore, it needs a certain amount every day in order not to have to break down its own muscle mass for the daily required amount of protein. Since there are many different lego building blocks, it is best to vary your diet as much as possible. This way you ensure that you are consuming a high number of different amino acids.
What contains a lot of proteins?
As mentioned, you can control your protein level primarily through your diet. Basically, you can say that all animal foods (e.g. fish, meat, sausage) or animal products (cheese, eggs) contain a relatively high amount of high-quality protein. Plant-based foods such as cereals, bread, pasta or rice also contain protein. Fruits and vegetables, as well as fats and sugar contain little or no protein.
How much protein should I eat?
People on dialysis are recommended to have a protein intake of about 1.1 g per kg of target weight per day. For example: with a body weight of 70 kg, this corresponds to a daily protein intake of 77 g. But how much is that? In many countries, a daily protein intake of 0.8 g per kg is recommended for the general population. As you can see, your protein requirement as a dialysis patient is higher than for people who do not dialyze. Please consider this calculation as an approximate guideline. The exact amount of protein you need requires an individual recommendation from your nephrologist and nutritionist specialized on dialysis.
What happens in case of under- and oversupply?
Older people with kidney disease in particular often consume too little protein. There are estimates that 40-70% of people on dialysis are malnourished. This is not good, because people who are undersupplied lose muscle mass particularly quickly. It in turn leads to physical weakness. As a result, malnutrition can lead to health problems.
With an over-supply of protein, you basically gain body weight. In principle, however, this is a rather rare problem to have, when you are a dialysis patient.
Do I feel that I am taking too little protein?
You can notice malnutrition when you feel tired and physically weak. Your doctor will medically diagnose malnutrition based on a set of parameters. Signs can be a weight loss of more than 5% in 3-6 months, a BMI below 20, or a serum albumin below 35 g/l. You don't need to know this - it's just in case you really wanted to know the details.
What do I have to consider when eating a high-protein diet as a dialysis patient?
The key challenge with a high-protein diet and dialysis is that, unfortunately, protein-rich foods are usually also high in phosphorus. Since many dialysis patients are often advised to adhere to a phosphate-reduced diet to avoid dangerous cardiovascular problems, this usually presents a difficult conundrum for some at first: "How am I supposed to eat a diet high in protein but low in phosphate?"
To make things easier for you, you can find the phosphorus-protein-quotient (PEQ) of foods in the Miku app. This tells you how many milligrams of phosphorus per gram of protein something contains. The lower this number, the better it is for you as a dialysis patient. You can also filter recipes and foods according to search criteria such as "high protein" and "low phosphate" in the food section of the app.
What does this mean for my diet now?
You should make sure that you are getting enough protein in your diet. However, you should also always keep an eye on the phosphate in protein-rich products. In the Miku app you will find many practical nutrition tips, examples and tricks.
Dialysis (especially PD) filters some of the protein back out of your body, which is why you should eat more protein than usual as a dialysis patient
Especially older people with renal failure do not consume enough protein, which often leads to malnutrition
Make sure you keep your protein and phosphate in balance by trying to favour foods that are low in phosphate but high in protein
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