Chronic Kidney Disease #2: Nutritional Management and Sarcopenia

Doctor's Insight.

Hello and welcome to Doctor's Insight.

The most basic method for managing chronic kidney disease or CKD is to follow a suitable eating plan.

The foods to watch out for are meat, fish, dairy products, eggs and beans.

Many of us eat these foods on a daily basis.

They contain protein which is essential for our body.

However, for people with kidney disease called CKD, it is fundamental to restrict protein intake.

If you like meat or cheese, this restriction would not be easy.

Plus, protein is the source of building muscle.

Is it safe to restrict your protein intake?

For CKD patients, especially in older adults, protein intake restriction can often cause a major problem.

It is called sarcopenia, a condition of a great loss of muscle mass.

Today, we will focus on the nutritional management for CKD and sarcopenia.

Today's expert is Dr. Masaomi Nangaku, President of the International Society of Nephrology.

He is a world-renowned nephrologist who has spent decades conducting research on the cause and the treatment of kidney disease.

Dr. Nangaku, we're happy to have you on our show again.

Happy to be here.

Today, we're going to talk about a kidney-friendly eating plan for people with CKD, which basically is to limit protein intake.

But this can lead to sarcopenia, a condition of significant muscle loss.

Dr. Nangaku, do many CKD patients suffer from sarcopenia?

There are multiple diagnostic criteria for sarcopenia and they are not standardized, so the worldwide figures are unknown.

I see.

We physicians generally feel that among elderly patients, those with CKD are 2 to 3 times more likely to suffer from sarcopenia compared to those without CKD.

What happens when you have both chronic kidney disease and sarcopenia?

This increases your risk of complications.

They are more likely to suffer from a heart attack or a stroke, which increases the risk of death.

So, what should elderly CKD patients do to lower their risk?

Particularly for elderly patients, it is important to ask a physician to determine whether to restrict your protein intake or somewhat reduce your intake while assessing your overall muscle mass.

How is sarcopenia diagnosed in CKD patients?

The doctor looks to see if the patient is underweight, moves slowly, or has difficulty getting up from a chair.

Based on these observations, the doctor may conclude that the patient has sarcopenia or is at high risk of developing it.

How do you restrict protein if you are considered to be at high risk for sarcopenia?

Restricting protein and reversing sarcopenia are two contradicting concepts, so patients cannot do both at the same time.

That's why it is up to the doctor to decide which to prioritize.

It is important to have regular kidney tests in order to monitor the speed of CKD progression.

If the results of your regular exam indicate that the risk of sarcopenia is greater than the risk of CKD progression, the doctor will prioritize sarcopenia treatment and ease the restriction on protein intake.

On the other hand, if the risk of CKD progression is greater than the risk of sarcopenia, you will continue restricting protein in your diet.

However, if you start dialysis, the treatment will replace the functions of your kidneys, and you no longer have to be concerned about the declining kidney function.

As a result, you will be able to ease the restriction on protein intake.

Everyone, even healthy people without CKD, lose muscle mass as we get older.

If the restriction is eased, it's important to take in an adequate amount of protein in preparation for the future.

Now, how about in the case where the risk of CKD progression outweighs sarcopenia?

Why is it necessary to restrict protein intake?

What exactly is happening inside the kidneys?

Let's look at the relationship between the kidneys and protein intake.

When you eat, kidneys remove waste products of protein metabolism in the form of urine.

That's why when you take in too much protein, it results in more waste products.

This does not pose any problems for healthy people, but for those with CKD, this puts a strain on the kidneys and can lead to the progression of the disease.

That's why, for patients with CKD, protein restriction is fundamental except in the early stages.

So what is the recommended amount of protein intake for people who require restriction?

0.6~1.0 grams per day per 1 kilogram of body weight.

For example, a person that is 175 cm tall can consume 40 to 67 grams of protein per day.

For instance, if we're talking about lean beef, the person could consume 180 to 300 grams.

We just saw some meat.

But when we add other dishes on the side, even a small amount of fish, eggs or dairy product, it exceeds the recommended amount.

What does this amount mean for a CKD patient?

Well, the patient will need to be creative in order to feel satisfied.

The first step is to increase the amount of low protein foods.

This way, you will get enough to eat and avoid becoming malnourished.

Dr. Nangaku, if we can't take in much meat, fish, beans or dairy products, what are we supposed to eat?

The three major nutrients in food are protein, carbohydrates and fat.

By deliberately increasing the amount of carbs and fat, you can compensate for the protein reduction.

Good sources of carbohydrates are rice, bread, noodles, pasta, potatoes, fruit and sugar.

However, it's important to note that foods that are high in carbohydrates often contain a small amount of protein.

In some regions, low-protein products such as bread, pasta and rice are available, making it easy to use as a part of your diet.

Large amounts of lipids are found in fat and oil.

It's recommended to use plant oil, such as olive oil and sesame oil.

I've heard of some low-protein carb foods.

The amount of protein is reduced by as much as 25 times the original amount in some rice or bread.

That would be easy to eat.

However, depending on where you live, it may be difficult to buy low-protein carb foods.

In such cases, potatoes, fruits and sugar can be used because they are low in protein.

Please remember that people with diabetes or obesity should always follow the advice they get from their doctor or dietician especially regarding the intake of sweet and fatty foods.

What else should CKD patients consider in their diet?

For patients who are on protein restriction, if their energy intake is low, the body will break down more and more muscle mass and convert it to energy.

In other words, the risk of sarcopenia further increases.

That's why they need to consume enough energy every day.

Again, it's important to compensate their protein reduction with carbohyates and fat.

It is also essential to continue daily exercise to the extent they are comfortable with, in order to maintain their muscle mass.

Thank you for those tips.

I think people would crave the foods they are restricted from eating.

Can patients actually follow this diet plan?

It is very difficult.

But recently, new drugs that suppress the decline of kidney function have been developed and are now available for many patients.

We hope that these new medications will help make it more feasible for patients to continue their restrictive diet plans.

We'll discuss more on chronic kidney disease medications in our next episode.

Dr. Nangaku, thank you so much for your time today.

It was my pleasure. Thank you.