If you have kidney disease or kidney failure, your doctor may have prescribed a diet to lower creatinine levels.
Video of the Day
Creatinine is a byproduct of the metabolism of creatine in muscle and the breakdown of protein from the foods you eat. With normal kidney function, your kidneys filter creatinine from your blood and excrete it through your urine.
"High creatinine levels indicate that the kidneys are not flushing out toxins that should be removed from the body. It's important for patients to find out what their creatinine levels are during their yearly checkup," says David P. Selzer, MD, a nephrologist at NYU Langone Medical Associates in West Palm Beach.
Some people are at higher risk for kidney disease than others, so your doctor may recommend following a diet to lower high creatinine levels to help protect your kidney function and overall health.
What Causes High Creatinine Levels and Kidney Disease?
People who have diabetes and hypertension are at higher risk for kidney disease because these conditions put more stress on the kidneys and force them to work harder, says S. Adam Ramin, MD, urologist and medical director of Urology Cancer Specialists in Los Angeles, California. Older adults are also at risk for kidney disease because kidney function lowers with age.
"The main causes of kidney disease are high blood pressure and diabetes. Hypertensive nephropathy and diabetic nephropathy both cause injury to the kidney due to increased pressure on the kidney. This leads to an inability to filter toxins out of the body," Dr. Selzer says.
People who are diagnosed with kidney disease often don't have any symptoms until they're in the later stages of the disease. At that point, people will often have fluid retention, swelling and a decrease in urinary output, says Mariselis Rosa-Sanchez, MD, a pediatric nephrologist at KIDZ Medical Services.
That's why it's incredibly important to see your primary care doctor every year to check your creatinine levels, which are evaluated when you leave a urine and blood sample. If you have kidney damage, blood creatinine levels will go up while the amount of creatinine in your urine goes down.
Testing for Kidney Disease
If you have high creatinine levels, your doctor may order additional tests, such as a creatinine test and a kidney test called blood urea nitrogen (BUN), which measures the amount of urea nitrogen — a waste product your kidneys remove — in your blood, according to the U.S. National Library of Medicine. High BUN levels indicate that your kidneys aren't operating at their best.
But Dr. Rosa-Sanchez says that a better indicator of kidney health is your cystatin C levels, which is a protein your cells produce. Unlike your creatinine levels, which your muscle mass and diet can influence, measuring cystatin C levels in your blood helps your doctor determine how well your kidneys are functioning.
Diet for People With Kidney Disease
People with kidney disease or kidney failure should focus on following a diet low in protein. Eating too much protein, especially animal protein and processed meats, forces your kidneys to work harder to excrete creatinine, Dr. Rosa-Sanchez says.
People with poor kidney function should limit their daily protein intake to 45 grams, while those with moderate kidney function can have up to 60 grams of protein a day, Dr. Ramin says.
"Lean sources of protein, such as chicken and fish, are better than fattier cuts for people with kidney disease, but you still want to lower your overall protein intake," he says.
Dr. Rosa-Sanchez recommends choosing plant-based protein instead, such as tofu, beans, tempeh, lentils and quinoa, and loading up on vegetables and fruits, which provide antioxidants, vitamins and fiber that can help protect your kidney function and reduce your risk of other chronic diseases.
"Animal protein contains more acid (as in amino acids) whereas plant protein is more alkaline. Too much animal protein can lead to acidosis, which can tax your kidneys even more," she says. "You want to fill 50 percent of your plate with vegetables and fruits, 25 percent with protein and the rest with fiber, such as whole grains."
According to a September 2021 review in Clinical Kidney Journal, increasing fiber intake in people with chronic kidney disease can help reduce complications and improve overall health by promoting good gut bacteria and reducing inflammation and uremic toxin production.
If you have diabetes, you want to be mindful of your fruit and whole grain intake, which can raise your glucose levels, Dr. Ramin says.
Healthy fats, such as extra-virgin olive oil, are also a great addition to your meals. But nuts (which are also high in healthy fat) can be high in sodium and protein so you want to limit them as well.
People with kidney disease also need to reduce their overall sodium intake because high-sodium foods retain fluid — and you want to help your kidneys do their job of filtering creatinine from your blood and removing waste products. Too much sodium can also raise your blood pressure.
"Lowering your sodium is important because a failing kidney won't be able to filter all the salt out. Maintaining too much salt drives up your blood pressure and puts you at risk for heart attack and stroke," Dr. Ramin says.
Because your potassium levels increase when your kidney is unable to remove creatinine, people with kidney disease also want to reduce the amount of potassium in their diet, Dr. Selzer says. If your potassium levels are too high, it can lead to an irregular heartbeat or a heart attack, according to the National Kidney Foundation (NKF).
"When creatinine levels are elevated, the number one problem that patients face is high potassium. Eating a low-potassium diet is often the most needed for patients with severe kidney injury," Dr. Selzer says.
Some foods high in potassium include artichoke, broccoli, butternut squash, oranges, kiwi and mango, per the NKF.
Working closely with your nephrologist or a registered dietitian who specializes in treating kidney disease can help you come up with a meal plan to lower creatinine levels and retain kidney function.
Why Hydration Is So Important
Staying hydrated is important for people with high creatinine levels due to kidney disease because it helps your kidneys filter out the excess creatinine in your blood, Dr. Rosa-Sanchez says.
"You want to drink pure water — not alkaline water, juice or drinks with electrolytes like Gatorade," Dr. Ramin says. "People who work out more produce more creatinine so they need to hydrate more than others."
If your urine is clear to light yellow, it means you're well-hydrated. However, if your urine is dark yellow, it means you're dehydrated, Dr. Ramin says.
Supplements and Medications for Kidney Disease
The treatment for kidney disease depends on what's causing it — there aren't any medications that specifically treat kidney disease.
For example, if it's diabetes or hypertension, your doctor will treat those conditions to help you maintain kidney function, Dr. Rosa-Sanchez says. Dr. Ramin says two classes of anti-hypertensive medications that are used to lower blood pressure are ACE (angiotensin-converting enzyme) inhibitors and ARBs (angiotensin II receptor blockers). These drugs work to lower blood pressure in a way that protects your kidneys.
People with kidney disease are also often prescribed a supplement called Nephro-Vite, which contains a combination of vitamins needed for folks with kidney failure and aid in excreting creatinine from the body, Dr. Ramin says.
What to Limit or Avoid
Taking other supplements, like protein powders, antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs) can raise creatinine levels in the blood, so you want to be mindful of them if you have kidney disease, Dr. Rosa-Sanchez says.
- National Kidney Foundation: "Apples are Okay, but Bananas are not...Top 10 Dialysis Diet Tips"
- International Journal of Biological Macromolecules: "Protective Effect of sulfated Chitosan of C3 Sulfation on Glycerol-Induced Acute Renal Failure in Rat Kidney"
- HealthLinkBC: "Creatinine and Creatinine Clearance"
- NIH: "Eating Right With Kidney Failure"
- MedlinePlus: "Creatinine"
- Journal of Renal Nutrition: "Foods with Added Fiber Lower Serum Creatinine Levels in Patients With Chronic Kidney Disease"
- Better Health Channel: "Kidney Disease"
- Beaumont Hospital Kidney Center: "Dietary Advice For Kidney Patients"
- U.S. Library of Medicine: "Creatinine Test"
- Clinical Kidney Journal: "Fiber Intake and Health in People With Chronic Kidney Disease"
- National Kidney Foundation: "Potassium and Your CKD Diet"