Raising your GFR (glomerular filtration rate) comes down to protecting the kidney function you still have and, in some cases, reversing temporary drops caused by dehydration, uncontrolled blood pressure, or poorly managed blood sugar. A normal eGFR for adults is above 90, though it naturally declines with age. The average for someone in their 60s is around 85, and for those over 70, it’s about 75. If your number has dropped below what’s expected for your age, there are concrete steps that can slow further decline and sometimes push it back up.
What Your eGFR Number Actually Means
Your eGFR estimates how well your kidneys filter waste from your blood, measured in milliliters per minute. It’s calculated from a simple blood test that measures creatinine, a waste product from muscle metabolism, then adjusts for your age and sex. The current standard formula, adopted in 2021, no longer includes a race variable.
The stages of kidney disease are defined by eGFR ranges. An eGFR of 60 to 89 suggests early-stage kidney disease. Between 45 and 59 is mild to moderate loss. Between 30 and 44 is moderate to severe. Below 15 is kidney failure. Knowing your stage matters because the strategies that help at stage 2 are different from those at stage 4, and some interventions work better the earlier you start.
Rule Out a Temporary Drop First
Before assuming your kidneys are damaged, consider whether dehydration skewed your result. When you’re underhydrated, your blood becomes more concentrated, creatinine levels rise, and your eGFR reads lower than your actual kidney function. In one study of 102 adults, people who drank less than 1.5 liters of water per day had average creatinine levels of 1.05 mg/dL, while those drinking more than 2.5 liters averaged 0.85 mg/dL. That difference is enough to shift an eGFR result by several points.
If you were dehydrated, hadn’t eaten in a while, or had an unusually intense workout before your blood draw, ask for a retest after a few days of steady hydration. Drinking around 2 liters of water daily is a reasonable baseline for most people, though your needs may vary with body size, climate, and activity level. Don’t overdo it either: excessive water intake can dilute electrolytes and stress the kidneys in its own way.
Control Blood Pressure Aggressively
High blood pressure is one of the top two causes of kidney disease, and it’s also the most modifiable factor once kidney function has started to decline. Uncontrolled blood pressure damages the tiny blood vessels inside the kidneys, gradually reducing their filtering capacity. Current guidelines for people with chronic kidney disease recommend targeting a systolic blood pressure (the top number) of 120 mmHg or lower when tolerable. If that causes dizziness or other side effects, aiming below 130 is the next best target.
For many people, this means taking blood pressure medication consistently, not just when they remember. It also means reducing sodium intake, which directly affects fluid balance and blood pressure. Cutting processed foods, canned soups, and restaurant meals can meaningfully lower sodium consumption without counting every milligram.
Manage Blood Sugar if You Have Diabetes
Diabetes is the other leading cause of kidney decline. Chronically elevated blood sugar damages the kidney’s filtering units over years, and the relationship between blood sugar control and kidney outcomes is well established. For people who already have both diabetes and kidney disease, an HbA1c between 6% and 7% appears to be the target that minimizes the risk of diabetes-related death. A large observational study of over 6,000 patients found that risk increases significantly as HbA1c moves above 7.5%.
Interestingly, pushing blood sugar too low is also dangerous when you have reduced kidney function. Damaged kidneys are less efficient at clearing insulin and certain diabetes medications from the blood, which makes episodes of dangerously low blood sugar more likely. This is why the “sweet spot” matters: tight enough control to protect your kidneys, but not so aggressive that you risk hypoglycemia.
Adjust Your Protein Intake
Your kidneys have to work harder to process protein. When kidney function is already reduced, a high-protein diet accelerates the decline by forcing the remaining healthy tissue to overperform. Current guidelines for people with kidney disease generally recommend limiting protein to about 0.8 grams per kilogram of body weight per day. For a 170-pound person, that’s roughly 62 grams of protein daily, which is less than many people eat without thinking about it.
This doesn’t mean avoiding protein entirely. It means being intentional: choosing quality sources, spreading intake across meals, and cutting back on the large portions of meat or protein shakes that are common in Western diets. A dietitian who specializes in kidney disease can help you find the right balance, especially if you’re also managing diabetes and need to coordinate carbohydrate and protein targets simultaneously.
Understand How Certain Medications Help
Two classes of medication play a major role in protecting kidney function. The first group, which lowers blood pressure by relaxing the blood vessels leading into the kidneys, reduces the pressure inside the kidney’s filtering units. This slows the damage caused by hyperfiltration (when remaining kidney tissue is forced to work too hard). These medications often cause a small, temporary dip in eGFR when you first start taking them, which can be alarming. That initial drop is actually a sign the drug is working: it’s reducing the harmful pressure inside the kidneys, trading a small short-term number decrease for long-term preservation of function.
A newer class of medications, originally developed for diabetes, has shown striking kidney benefits. These drugs were approved by the FDA between 2020 and 2023 specifically to reduce the risk of sustained eGFR decline, kidney failure, and cardiovascular death in adults with chronic kidney disease, even in people who don’t have diabetes. If your eGFR is declining and you aren’t already on one of these medications, it’s worth discussing with your doctor.
Stop Smoking
Smoking accelerates kidney damage through several pathways: it raises blood pressure, reduces blood flow to the kidneys, and promotes inflammation in blood vessel walls. Research shows that the harmful effects of smoking on kidney filtration appear to be reversible after quitting. While the age-related decline in kidney function happens at a similar pace regardless of smoking status, the additional damage layered on top by active smoking can be removed from the equation by stopping.
Avoid Supplements That Harm Kidneys
Many herbal supplements and high-dose vitamins are directly toxic to the kidneys. The list of supplements linked to kidney injury in published case reports includes St. John’s wort, thundergod vine, tribulus, wormwood, creatine, chromium, glucosamine, and high doses of vitamins A, C, and D. Star fruit is specifically dangerous for anyone who already has kidney disease.
The challenge is that supplement labels often don’t warn about kidney risks, and many people assume “natural” means safe. If your eGFR is low, review every supplement you take with someone who understands kidney function. Some products contain unlisted ingredients or contaminants that compound the problem.
What Realistic Improvement Looks Like
If your low eGFR was caused by dehydration, a medication side effect, or an acute illness, you may see a rebound of 10 or more points once the cause is addressed. If you have established chronic kidney disease, the goal shifts from dramatic improvement to stabilization and slowing the decline. A stable eGFR over two to three years is a genuine success in CKD management.
Some people do see modest increases of a few points after getting blood pressure and blood sugar under control, losing excess weight, or starting kidney-protective medications. But the gains tend to be gradual, measured over months rather than weeks. Repeated testing matters: a single eGFR result is a snapshot, and your doctor will look at the trend across multiple blood draws before drawing conclusions about whether your kidney function is improving, stable, or declining.