Kidney function can be preserved and its decline slowed through a combination of lifestyle changes, dietary adjustments, and in some cases medication. True reversal of kidney damage is rare once significant scarring has occurred, but the rate of decline is highly modifiable. People who take an active approach can keep their filtration rate stable for years longer than those who don’t.
Physical Activity Slows Kidney Decline
Exercise is one of the most effective non-drug interventions for protecting kidney function. A study published in the Journal of the American Society of Nephrology tracked people with chronic kidney disease (CKD) over nearly four years and found that those who exercised more than 150 minutes per week lost filtration capacity at a rate of 6.2% per year, compared to 9.6% per year for inactive participants. Each additional 60 minutes of weekly activity was linked to a 0.5% slower annual decline.
The mechanism goes beyond general fitness. Kidney disease triggers a cascade of harmful processes: elevated inflammation, insulin resistance, oxidative stress, and blood vessel dysfunction. Aerobic exercise directly counteracts these processes, reducing the inflammatory signals and metabolic dysfunction that accelerate kidney scarring. Both walking and moderate-intensity cardio count. You don’t need intense training to see benefits.
Dietary Protein: How Much Is Too Much
Your kidneys filter the waste products of protein metabolism, so eating less protein reduces their workload. For people with moderate to advanced CKD (filtration rates below 45), guidelines recommend 0.6 to 0.8 grams of protein per kilogram of body weight per day. For a 170-pound person, that works out to roughly 46 to 62 grams daily, which is noticeably less than the typical Western diet provides.
This doesn’t mean eliminating protein entirely. The goal is a modest, individualized reduction. Protein quality matters too. Plant-based proteins tend to produce fewer of the acidic waste products that stress the kidneys compared to animal sources. A dietitian familiar with kidney disease can help you find the right target based on your stage of CKD, nutritional needs, and lab results.
Sodium, Potassium, and Phosphorus
Sodium is the mineral most people with kidney concerns need to reduce first. The general recommendation is no more than 2,300 milligrams per day, but many people with CKD need to go lower. Most excess sodium comes from processed and restaurant foods rather than the salt shaker, so reading labels and cooking at home makes a bigger difference than simply putting away the salt.
Potassium and phosphorus are trickier because the right amount depends on your kidney function and blood levels. Healthy kidneys regulate these minerals easily, but as function declines, both can build up in the blood and cause serious problems, including heart rhythm disturbances (potassium) and bone weakening (phosphorus). There’s no single milligram target that applies to everyone. Your blood work will determine whether you need to limit high-potassium foods like bananas, potatoes, and tomatoes, or cut back on phosphorus-heavy items like dairy, processed meats, and dark colas.
The Truth About Drinking More Water
The advice to “drink more water for your kidneys” is more nuanced than it sounds. For healthy people, staying well-hydrated supports normal kidney function. But for people with existing kidney disease, pushing extra fluids can actually backfire. A study of 581 CKD patients found that those with the highest daily urine volumes (above 2.85 liters) experienced faster declines in filtration rate than those producing less than 2 liters per day.
As kidneys lose function, they also lose the ability to concentrate urine efficiently, which naturally increases thirst and urine output. Forcing fluids beyond what thirst dictates can overwhelm the kidneys’ reduced capacity to dilute urine, potentially leading to dangerously low sodium levels in the blood. Current guidance for people with kidney disease: let thirst be your guide rather than aiming for a specific number of glasses per day.
Medications That Protect the Kidneys
Two classes of medication have changed the outlook for people with kidney disease in recent years. The first, known as SGLT2 inhibitors, were originally developed for diabetes but turned out to have powerful kidney-protective effects regardless of whether someone has diabetes. International guidelines now recommend them for most people with CKD and significant protein in the urine. These drugs work partly by reducing the pressure inside the kidney’s filtering units, giving them a chance to recover from overwork.
The second class, GLP-1 receptor agonists (also originally diabetes drugs), showed impressive results in the FLOW trial: a 24% reduction in the risk of severe kidney decline, kidney failure, or death from kidney or cardiovascular causes. They also reduced overall mortality by 20%. When used together, SGLT2 inhibitors and GLP-1 receptor agonists appear to have additive benefits, meaning each one contributes protection independently of the other.
For people with CKD who develop metabolic acidosis, a condition where the blood becomes too acidic because the kidneys can no longer excrete enough acid, oral bicarbonate supplements may help. A meta-analysis of 15 trials found that sodium bicarbonate slowed kidney function decline and cut the risk of reaching kidney failure by about 47%. The evidence is still considered preliminary, but it’s a low-cost intervention your doctor may consider if your blood bicarbonate levels are low.
Medications That Harm the Kidneys
One of the simplest ways to protect your kidneys is to stop taking drugs that damage them. The biggest culprits are NSAIDs: ibuprofen (Advil, Motrin), naproxen (Aleve), and similar anti-inflammatory painkillers. These drugs reduce blood flow to the kidneys, and people with a filtration rate below 60 should avoid them entirely. Even occasional use carries risk when kidney function is already compromised.
NSAIDs are also hidden in combination products like cold and flu medicines, so always check labels for the word “NSAID” before taking anything over the counter. High-dose aspirin (above 325 mg per day) acts the same way on the kidneys and carries the added risk of severe bleeding. Acetaminophen (Tylenol) is generally considered safer for kidney patients who need pain relief, though it still requires appropriate dosing.
Blood Pressure and Blood Sugar Control
High blood pressure and diabetes are the two leading causes of kidney disease, and controlling both is essential for slowing further damage. Uncontrolled blood pressure physically damages the tiny blood vessels in the kidneys over time, while high blood sugar triggers inflammation and scarring in the filtering units. Even modest improvements in either one reduce the rate of kidney decline.
For people with diabetes and kidney disease, current guidelines suggest layering kidney-protective medications (like SGLT2 inhibitors and GLP-1 receptor agonists) on top of standard blood pressure drugs. A newer class of blood pressure medication called nonsteroidal mineralocorticoid receptor antagonists may be added for people with type 2 diabetes who still have protein leaking into their urine despite standard treatment, provided their potassium levels and filtration rate are in a safe range.
Putting It Together
No single change will dramatically improve kidney function on its own. The real benefit comes from stacking multiple strategies: getting at least 150 minutes of physical activity per week, moderating protein intake, keeping sodium low, avoiding NSAIDs, managing blood pressure and blood sugar tightly, and working with your care team on medications that actively protect the kidneys. Each of these interventions shaves a small percentage off the annual rate of decline, and together they can mean the difference between stable kidney function for decades and a much faster path toward dialysis.