Renal diet: The right food for chronic kidney disease patients
Chronic kidney disease (CKD) is an important issue that is more widespread than you might think: An estimated 35 million American adults (approximately 15 percent of the U.S. population) suffer from it today. Unfortunately, 90 percent of those affected do not even know that they are sick and should be taking steps to counteract the fast progression of their ailment. And even more frighteningly, CKD has become the ninth most common cause of death in the United States.
When diagnosed with chronic kidney disease, patients tend to become overwhelmed by their dietary restrictions. They often feel like these limitations determine their whole lives: It can be frustrating to say “no” to barbecues, snacking with colleagues or family dinner due to fear of the disease growing worse. Even a quick meal can turn into an absolute ordeal if ingredients are not selected and prepared carefully in advance.
With this article, we will help you to bring back normality to your restricted life. We will inform you about chronic kidney disease and how a renal diet will improve your health and help slow down the progression of your illness.
Small organs with a big impact
Our two bean-shaped kidneys are about 4–5 inches (approx. 13 cm) long. Their main job is to filter nutrients from the bloodstream and to eliminate waste materials. Kidneys maintain our fluid balance and therefore have a substantial effect on blood pressure control.
So, where are the kidneys located? These small organs sit opposite each other on the left and right side of a region of the trunk called flank and are situated towards the back.
There are two kidneys located in the left and right side of your trunk
Once you have suffered from kidney pain, you will have no doubts about the exact position of your kidneys. But if you have not had this experience yourself, you might be wondering: What does kidney pain actually feel like? It is a constant dull ache occurring in the left, right or both flanks. These areas are sensitive to the touch: The pain gets worse when you tap against the affected kidney.
When your kidneys hurt, you should pay immediate attention to this signal. Both kidneys are surrounded by muscles and bones that can also be responsible for pain. But especially if additional symptoms like bloody urine, fever or nausea appear, visiting a doctor becomes a must.
What causes kidney disease?
Over time, different health problems can harm our kidneys bit by bit, which accumulates kidney stress and might lead to chronic kidney disease.
In the United States, diabetes type 2 and high blood pressure are the main causes for kidney stress. Other problems like autoimmune diseases, inherited diseases as well as nephrotic syndrome causing abdominal swelling and urine enriched in protein (proteinuria) may also induce kidney failure.
“Diabetes type 2 and high blood pressure are the main causes for kidney stress.”
The first signs of chronic kidney disease
Kidney pain is actually not the first sign that something is wrong. If your kidneys start hurting, you may have missed other warning signals beforehand. The first signs of chronic kidney disease are:
- you feel less energized and you are always tired
- you cannot concentrate
- you suffer from sleeping problems and muscle cramps during the night
- you experience abdominal swelling
- your skin becomes dry and itchy
- your frequency of urination has increased and you need to visit the bathroom during the night
Every disease comes in stages
Chronic kidney disease does not appear overnight, it develops over the span of years.
Ultimately, CKD will always lead to kidney failure, as the disease cannot be cured. However, its progression can be slowed down in order to delay dialysis significantly.
CKD is subdivided into five stages to help classify the progression of the disease. But before we dive into the clinical stages of CKD, we need to understand how it is diagnosed.
To measure the function of kidneys, doctors determine the glomerular filtration rate (GFR) through testing. The GFR describes how well kidneys filter the blood. In case of a suspected issue in this regard, your doctor will order blood tests that measure your serum creatinine.
The glomerular filtration rate determines the disease stage
Creatinine is a waste product that is built up after muscle activity. Well-functioning kidneys completely remove creatinine from the bloodstream, while slowed-down kidney function will raise blood creatinine levels.
In the classification of CKD mentioned above, there are five stages representing the severity of this disease. Each stage has its own recommendations for specific treatment and food selection:
- Stage 1 with normal or high GFR (GFR > 90 ml/min): At this stage, the kidneys are doing a decent job but do not function at 100 percent of their capacity. Most people do not experience symptoms at this point. This early stage of the disease can be stabilized with a healthy and nutrition-rich diet.
- Stage 2 with mild reduction (GFR = 60–89 ml/min): This stage is similar to the first one. Mostly, patients in this category are diagnosed through diabetes or hypertension screening. Patients at this stage have to make sure that they are both consuming a well-balanced diet and keeping their blood pressure in a healthy range.
- Stage 3A with mild-moderate reduction (GFR = 45–59 ml/min) and Stage 3B with moderate-severe CKD (GFR = 30–44 ml/min): At this point, symptoms such as tiredness or abdominal swelling become more obvious. Patients should be following a healthy diet that is high in plant-based foods and lower in protein, sodium, and saturated fat. Sodium restriction is important for controlling blood pressure. For stages 3A and 3B, doctors will most likely prescribe medicine to control blood pressure.
- Stage 4 with severe reduction (GFR = 15–29 ml/min): Patients at this stage usually need dialysis or kidney transplantation because the kidney damage is severe. At this point the symptoms grow more drastic: Nausea and vomiting can appear, kidneys will start hurting and urea buildup in the blood leads to bad breath. At stage 4, patients have to visit a specialist (nephrologist) every three months. People affected should reduce protein consumption to limit protein waste, avoid smoking and exercise regularly to help prolong kidney function.
- Stage 5 with kidney failure (GFR <15 ml/min): At this point, it is likely that the patient’s kidneys have given up their function completely. The kidneys are no longer able to remove toxins and fluids, which consequently accumulate in the body, causing an overall feeling of sickness. Dialysis and kidney transplantation are necessary for survival.
Is chronic kidney disease the end?
When a patient is diagnosed with chronic kidney disease and confronted with the scope of all the restrictions and treatments that now become necessary, they probably will feel like their ailment is the end of the world. And it is true that you can die from this disease if you do not take thorough care of yourself.
But in all of this dramatic news, there is still hope: By changing your lifestyle, you are most likely able to slow down the progression of your disease significantly.
“With changing your lifestyle, you are most likely to slow CKD progression.”
Can CKD improve?
Although chronic kidney disease is considered incurable, cohort studies have found that some patients with CKD actually show improved kidney function over time. In the studies at hand, the rate of patients experiencing an improvement amounted to 15 percent, of which 24 percent were patients with stage 4 and 5 CKD. The actual mechanisms of the improvement are still mostly unknown, but they appear to be associated with tissue recovery.
Medications to avoid with CKD
If your kidneys are chronically damaged, it is crucial to have your doctor approve any medication you take. Patients will want to avoid pain relievers with nonsteroidal anti-inflammatory functions like Aspirin, Ibuprofen, Naproxen and Celecoxib.
These drugs, also referred to as NSAIDs, affect renal blood flow and glomerular filtration, which can induce side effects in CKD patients. Furthermore, heavy use of NSAIDs has been shown to cause chronic kidney injury.
CKD patients should consult their doctor before taking medication
Proton pump inhibitors (PPI) to treat gastric acid-related diseases have been linked to a higher risk for CKD. Patients definitely want to avoid these kinds of drugs and, instead of treating the symptoms, should aim for the cause by reducing stress or changing their eating habits.
Any kind of drug that has to be processed by kidneys should be avoided or replaced with “kidney-friendly” medication. This includes antimicrobial medications (for example anti-fungal, antibiotic and antiviral) or diabetes drugs.
Stop kidney disease from progressing with renal diet
Nutrition is key for any kind of disease. Patients with kidney disease or chronic abnormalities in their kidney function benefit greatly from the right eating habits. For CKD, the clearly defined form of nutrition is called renal diet.
What is a renal diet?
When you are diagnosed with compromised kidney function, your main goal is to avoid waste material in your blood, which naturally occurs as a product of food digestion, liquid consumption or drug treatment.
Compromised kidneys cannot properly filter out waste of the body. If residues remain inside the body, this can cause electrolyte imbalances and substantially even more stress to your kidneys.
Keep sodium and phosphorus levels low
A renal diet is low in sodium, phosphorus and protein. Sodium is one of the three electrolytes that controls our fluid balance. Hydration is critical for maintaining our blood pressure and acid-base balance as well as our nerve and muscle function on a healthy level.
Chronic kidney disease patients should limit their sodium intake because their kidneys are unable to clear the excess sodium from their blood. Otherwise, this may cause fluid retention, high blood pressure and heart failure because an increase of fluid in the bloodstream means considerably more work for their heart.
“A renal diet is low in sodium, phosphorus and protein”
Extra phosphorus induces the release of calcium, which makes our bones weaker. The remaining calcium accumulates in our blood vessels and heart, leading to arterial calcification, which in turn increases the risk for cardiovascular diseases.
Consume more high quality proteins
Protein consumption is a tricky thing for damaged kidneys. The right amount is determined by the stage of the disease. However, protein is necessary for tissue maintenance and repair. When protein is consumed, make sure it comes from high-quality sources like eggs.
Keep an eye on potassium level
Some CKD patients experience hyperkalemia, an increase of the potassium level in their blood serum. Potassium is important for heart function and muscle activity. However, if it accumulates in the blood due to failed extraction, the muscle cells of the heart start to beat irregularly, which can cause heart attacks and death. In cases of hyperkalemia, potassium intake should thus be reduced.
Developing your renal diet
It is important that your ideal diet is adjusted step by step because everybody is different. We recommend working with a renal dietitian. It is also essential to control fluid consumption because neglecting it adds extra pressure on your body system. The right fluid intake, including fluids used for cooking, is calculated by a specialist and correlates with the urine output.
In the following, we have summarized the types of food you should focus on and those you should avoid if you are diagnosed with chronic kidney disease. Keep in mind that the right nutrition depends on the stage of your disease and should be discussed with your kidney specialist.
What can you eat on a renal diet?
Your main goal is to provide your body with high-quality nutrients that it can use up completely without producing waste:
- Give priority to fresh fruits and vegetables,
- Choose unsalted frozen food if you cannot prepare fresh food,
- Use egg whites as a protein source instead of egg yolk or meat, which come with a lot of phosphorus,
- Choose olive oil as source of anti-inflammatory fatty acids.
Always choose fresh fruits and vegetables for your renal diet
What can you not eat on a renal diet?
Anything that is high in phosphorus, potassium, and sodium puts additional pressure on your kidneys. Therefore, you may need to:
- Reduce portions of foods high in potassium such as avocado, banana, fish and potatoes,
- Reduce foods high in phosphorus such as fast food, meat, seeds and cola,
- Cut back on milk and dairy products,
- Avoid salt,
- Avoid marinated food with an excess of sodium, phosphorus or potassium,
- Cut down on food high in protein,
- Avoid processed food, as it contains lots of additives and chemicals that might not be cleared by your kidneys and may accumulate in your body.
What foods should you avoid with stage 3 kidney disease?
At stage three of chronic kidney disease, your kidneys can still clear potassium from your blood and remove excess fluids. Patients greatly benefit from a renal diet and with its help can manage their blood pressure, glucose and body weight.
Stage-three-patients should avoid unhealthy saturated fats as well as trans-fats and replace them with sources of unsaturated fatty acids like olive oil. Potassium intake does not have to be restricted, but patients should not consume more than 800 mg of phosphorus every day.
“At stage 3, your kidneys can still clear potassium and remove excess of fluids.”
The daily recommended protein intake is limited to 0.8 grams per kilogram of body weight. This usually means restricting the amount of meat you consume. Additionally, stage three CKD patients should reduce their sodium intake to 1,000–4,000 milligrams per day.
Finding alternatives is key
It can be frustrating to turn down a barbecue with your family and friends because you feel you cannot eat anything there. But this does not mean you should feel banned from any kind of social eating.
Instead of having heavy salted meat for your barbecue, you could put your favorite seasoning on veggies coated in olive oil and have a delicious meal that is also good for you. Finding alternatives requires a lot of research, but gives you the means to keep the disease from taking over your entire life.
How FLAVIS helps you
Flavis understands that a renal diet is very restrictive and limits your daily life. This is why we are developing food products for chronic kidney disease patients that are low in protein, phosphorus, sodium and potassium.
These products help you meet your daily limitations easily and in doing so support slowing down disease progression. In our product range you will find pasta, bread and sweet treats. This brings back that variety you love and have been missing ever since you had to restrict your choices of food.
Finding alternatives is key for your renal diet
Our products are completely safe for your friends and family to eat. It provides them with a quick healthy diet that relieves stress from their kidneys as well.
Additionally, this allows you to eat the same food as your friends and loved ones, so you feel like a part of them again. Nevertheless, we recommend reviewing our products with your dietitian or doctor that monitors the mineral intake according to your disease stage to ensure the best possible diet for you.
CKD restricts eating – but not your love of food
To slow chronic kidney disease progression you need to change your food habits, which can be very frustrating. Your daily goal is to limit your intake of potassium, sodium, phosphorus and protein according to the stage of your disease.
Treating CKD can feel like a lifelong ordeal, especially if you are a lover of meat, pasta and dairy. Finding alternatives that fit your needs is essential to not feel overwhelmed by this disease. Our CKD-friendly products take the food restrictions of renal diet into account – and out of your daily workload.
For a better quality of life.
Cover picture by Nathan Cowley, additional pictures by Romario Ien, Online Marketing, Laurynas Mereckas, Scott Warman and Cottonbro.