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Glomerular filtration rate (GFR) is a measure your doctor can take of how well your kidneys are working. You can improve your GFR and your kidney function by looking at your lifestyle, diet, and medications, and making certain changes.

Your kidneys are your body’s filtration system. They pull the water and nutrients you need from your blood, and send waste products, toxins, and extra fluid to the bladder to be released as urine. Your kidneys play a crucial role in regulating your body’s fluid and electrolyte balance, which can impact things like your heart rate and blood pressure.

When this filter isn’t working well, or if you’ve been diagnosed with kidney disease, you need to monitor your kidney health carefully. That’s because any imbalance in this system can affect the entire body. Keep reading to learn what you can do to improve your GFR and protect, or restore, your kidney health.

The glomerular filtration rate measurement comes from the name of the filtering units inside your kidneys, called the glomeruli.

Glomeruli are complex structures made of tiny blood vessels called capillaries, along with protein mesh and layers of tissue that continuously filter your plasma. Each glomerulus is housed within a structure called a Bowman’s capsule. Based on 2020 research, between your 2 kidneys, you have about 2 million glomeruli.

A number of formulas are used by groups like the National Kidney Foundation to calculate GFR. But the measurement essentially takes into consideration your gender, age, body size, and your blood creatinine level.

Creatinine is a waste product that your body creates as muscle breaks down. Everyone has some creatinine in their blood. Average levels range from:

  • 0.9 to 1.3 milligrams per deciliter in adult men
  • 0.6 to 1.1 milligrams per deciliter in adult women

These levels can vary. For example, in a 2009 research review, creatinine levels fell by an average of 0.4 milligrams per deciliter in pregnant women.

Because they can change with age and size, creatinine levels alone are not good indicators of kidney health. The GFR takes these other elements into account.

Most GFR results simply provide you with a measurement of 60 or higher, since you can have stage 1 or 2 kidney disease, but still have normal kidney function. This changes when your GFR drops below 60. Under 60, you begin to have some loss in function.

GFR and kidney disease stages

The National Kidney Foundation lists the following GFR scores and kidney disease stages, and what to expect in each:

GFRStageFunction
45– 59stage 3amild to moderate damage
30–44stage 3bmoderate to severe damage
15–29stage 4severe damage
under 15stage 5kidney failure

As you advance through the stages of kidney disease, you will notice more and more symptoms, and your treatments may need to become more intense.

Hemodialysis is a treatment where an artificial kidney filters and circulates your blood when your kidneys can no longer do their job. It’s a common method for managing end-stage kidney disease and kidney failure. However, with early diagnosis and careful management, you may be able to at least slow down the progression of your kidney disease.

In most cases, kidney disease is a chronic and gradually progressing disease. While it’s possible to improve your GFR, you’re more likely to do so with acute kidney injuries rather than with chronic kidney disease. For most people with chronic disease, positive lifestyle changes may help slow the loss of kidney function.

Some studies have shown that GFR may increase over time in people at all stages of kidney disease by:

  • Controlling blood pressure. You can manage high blood pressure through exercise, diet, stress reduction, and limiting alcohol, among other lifestyle choices.
  • Making sure you’re not deficient in vitamin D. Vitamin D deficiency is very common, and many people aren’t aware that they’re deficient. If you think you have a deficiency, talk with your doctor and get your blood levels tested. To increase your vitamin D levels, you can spend more time in the sun or add more vitamin D-rich foods to your diet.
  • Resolving other metabolic conditions. Metabolic disorders are complex and can present in many forms. Work with your doctor to find a treatment plan that addresses the root cause.

Here are other things you can do to help reduce further damage to your kidneys.

Eat well

A balanced diet can go a long way in protecting your kidneys. Some foods put more strain on the kidneys and are best avoided, especially if you have known kidney damage. These include foods high in potassium, phosphorous, and sodium, like:

  • avocados
  • bananas
  • canned foods
  • sodas
  • whole wheat bread
  • oranges and orange juice
  • brown rice
  • pickled foods
  • processed meats
  • starches
  • tomatoes
  • packaged meals
  • dried fruits
  • leafy green vegetables

Keep your heart healthy

Getting regular exercise and keeping your blood pressure in check can help protect your kidneys. High blood pressure can damage the delicate structures in your kidneys.

Watch your blood sugar

Controlling your blood sugar is key to avoiding kidney damage. This is especially true if you have diabetes. People with kidney disease who have diabetes are more likely to have severe complications or a quicker decline in kidney health than those with kidney disease who don’t have diabetes.

Drink enough water

Drinking enough water is good advice for anyone, but it can also help your kidney health. Staying hydrated can improve your kidney’s ability to filter toxins. Kidney experts recommend that you drink enough water to make around 2 liters of urine per day. If you’re wondering how much water that is, it’ll vary from person to person.

Dehydration concentrates your urine, which can cause damage. Exactly how much water you should drink is up for debate, and clinical studies are still investigating just how much water it would take to help your kidneys. They have shown that any benefit is only seen with plain water, not sweetened drinks.

There are other cases where you may need to limit how much water you drink. If you have severe kidney disease, your doctor may place you on a fluid restriction. This is because your kidneys are less effective at removing extra water from your body. The extra fluid can lead to swelling and edema, and may need to be removed by other means, like hemodialysis.

Ask your doctor about the medications you take

If your kidneys aren’t working well, or if you’ve been diagnosed with kidney disease, it’s important to talk with your doctor about any medications you’re taking. A number of medications can impair or cause damage to the kidneys. Your doctor can determine the best course of action in terms of stopping these medications or replacing them with a different kind of medication.

Medications that can cause problems with your kidneys — called nephrotoxins — include:

  • acetaminophen
  • aspirin
  • nonsteroidal anti-inflammatory drugs
  • lithium
  • diphenhydramine
  • benzodiazepines
  • several classes of antibiotics
  • contrast dye
  • chemotherapy drugs
  • some blood pressure medications
  • diuretics
  • some herbal remedies

People with kidney disease should also avoid using drugs including:

  • alcohol
  • cigarettes
  • cocaine
  • heroin
  • ketamine
  • methadone
  • methamphetamine

As for natural supplements, talk with your doctor before taking any herbal remedies or vitamins.

Kidney disease can develop slowly over time, but some symptoms may be a sign that something is wrong. These include:

  • itching
  • frequent or infrequent urination
  • fatigue
  • puffiness or swelling

Talk with your doctor about your risks for kidney disease, or any family history of kidney problems. Many times, people are diagnosed with kidney disease when routine lab work is done for another reason.

If you’ve been diagnosed with kidney disease, you can also talk with your doctor about any medications or supplements you’re currently taking, as well as your diet. Your doctor may ask you to make some changes to support your kidney health.

While few medications can help treat kidney disease, managing conditions like high blood pressure and diabetes can go a long way in extending the life of your kidneys.

Improving your GFR isn’t easy, but it can happen. To increase your GFR and your kidney function, talk with your doctor about changes you can make to your lifestyle and diet. You can also discuss any new medications or supplements you’re taking to increase kidney function.

The best thing you can do to protect your kidneys is to try to avoid damaging them in the first place. Avoid medications that are toxic to your kidneys, eat well, stay hydrated, and keep your blood sugar and blood pressure in control.