How to Improve Kidney Function During and After Cancer Treatment

Chemotherapy, radiation therapy and other cancer treatments put stress on your body. When this happens, the kidneys are often among the first organs affected. Understanding how to improve kidney function during and after cancer treatment helps protect these important organs.

“Kidney problems hinder your body's ability to remove waste products, excess fluid and acid,” says Dr. Eric Turner, a board-certified and fellowship-trained medical oncologist with Beaufort Memorial Oncology Specialists. “This disruption can lead to complications such as low red blood cell levels and heart issues, among other health concerns. Therefore, comprehensive cancer care must consider the health of the kidneys, as their functioning is critical to overall wellness.”

Keep reading to learn about the effect of cancer treatment on your kidneys and practical ways to protect and support kidney function throughout your cancer journey.

Why Cancer Treatment Affects the Kidneys

Many common cancer treatments can lead to kidney damage. This happens in one of three ways.

• Accidental exposure — Radiation therapy uses high-energy radiation to destroy cancerous cells. If radiation is given to organs near the kidneys, the kidneys can be affected. The damage can take a year or longer to appear.
• Filtering systemic therapies — Your kidneys filter everything that passes through your body. When it filters chemotherapy, immunotherapy and other systemic cancer treatments, the medication can damage blood vessels in the kidneys and cause other kidney damage.
• Side effects — Every type of cancer treatment comes with potential side effects. In some cases, side effects can affect the kidneys.

Read More: Get a Handle on Chemotherapy Side Effects

Signs Your Kidneys May Not Be Working Well

Many people with kidney disease don’t experience early warning signs. As a result, they don’t realize they have a problem until it progresses to chronic kidney disease (CKD).

When symptoms do begin, the National Kidney Foundation states they may include:

• Bloody or foamy urine
• Difficulty sleeping or concentrating
• Dry, itchy skin
• Lack of energy
• Muscle cramps
• Puffy eyes
• Reduced appetite
• Swollen feet and ankles
• Urinating more often than usual

Read More: Kidney Infection vs. UTI: Do You Know the Difference?

Steps to Protect and Support Kidney Function

“Healthy kidneys play a major role in your quality of life,” Dr. Turner says. “Whether you have risk factors for kidney failure, are undergoing cancer treatment or just want to feel your best, you can take meaningful steps toward protecting and supporting kidney function.”

A few steps to consider include the following:

• Choose pain medication wisely — Frequent use of nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen increases your risk of kidney disease. Acetaminophen is a better choice for pain. It’s less likely to damage your kidneys.
• Drink the right amount — Your kidneys need water to remove fluid from your body. Stay hydrated and drink the recommended amount of water per day.
• Exercise regularly — Physical activity helps your kidneys function. Aim for 30 minutes of moderate-intensity exercise most days of the week.
• Know your numbers — Lab tests can help determine how well your kidneys are working. Learn what your numbers are and what they mean for your health.
• Manage other health conditions — Other health conditions, such as diabetes and high blood pressure, put your kidneys at risk, according to the American Heart Association. Work with your care team to manage chronic health conditions properly.
• Stop smoking — Smoking makes it harder to manage high blood pressure and other chronic diseases that increase your risk for kidney problems. It also damages blood vessels throughout your body, including in your kidneys.

Before making any lifestyle change, talk to your care team.

Foods That Support Healthy Kidneys

To improve kidney function, it’s important to pay attention to your diet. Though food can’t completely protect your kidneys, a kidney diet protects your kidneys and gives you energy to make it through cancer treatment.

A dietitian can help develop a custom eating plan. Most often, your plan will focus on eating whole foods, such as fruits and vegetables, and limiting foods with certain minerals.

• Phosphorus — This is found nuts, dairy and more. It helps build strong bones, but too much can weaken them. Since kidneys aren’t great at removing phosphorus, you may want to limit how much phosphorus-rich foods and drinks you consume.
• Potassium — Oranges, tomatoes and potatoes are three foods high in potassium. The mineral helps your nerves and muscles function. According to the Centers for Disease Control and Prevention, chronic kidney disease can cause potassium to build up in your blood and cause heart disease.
• Sodium — Consuming less salt or sodium helps reduce your risk of fluid buildup and swelling. To consume less salt, flavor your foods with herbs and spices and avoid prepackaged, processed foods.

Read More: Your Immune System and Cancer: What’s the Connection?

Can Kidney Function Be Restored?

In certain cases, kidney function can be restored or improved. Experts indicate that successful restoration often hinges on whether the underlying kidney problem is temporary.

“For kidney function to improve, your kidney problem must be temporary,” Dr. Turner says. “Unfortunately, if you have developed chronic kidney disease (CKD) or kidney failure, improvement in function is unlikely, as these conditions can lead to permanent damage.”

To assess kidney function, healthcare professionals use a key measurement known as the estimated glomerular filtration rate (eGFR). This rate indicates how effectively your kidneys filter waste from your blood. The higher the eGFR score, the better the health of your kidneys:

• Normal (90–120 eGFR) — You have healthy kidneys.
• Early-stage kidney disease (60–90 eGFR) — Without proper management, you may develop chronic kidney disease.
• Kidney disease (15–60 eGFR) — Chronic kidney disease may have developed.
• Kidney failure (0–15 eGFR) — You may be in the final stage of kidney disease.

When to Talk With Your Care Team

Anytime you notice blood in your urine or other symptoms of kidney disease, contact your cancer care team immediately. However, you shouldn’t wait for symptoms to raise concerns about kidney health.

“The conversation should begin before treatment even begins,” Dr. Turner says. “Ask if your treatment puts your kidneys in harm’s way. Then find out how you can minimize its effect and maintain good kidney health along your cancer journey.”

In Summary: How to Improve Kidney Function

Cancer treatment can put extra strain on the kidneys, but you can take proactive steps to protect, support and improve kidney function.

1. Kidneys are one of the first organs affected by cancer treatment. This can occur with radiation therapy, chemotherapy and other treatment options.
2. To support good kidney health, adopt a healthy lifestyle. Don’t smoke, drink plenty of water, exercise regularly and manage other health conditions, such as high blood pressure.
3. It’s rare to reverse damage caused by chronic kidney disease. You may be able to improve your kidney function if cancer treatment or other issues cause temporary problems.

Find a cancer care specialist anytime online.