Your kidneys filter about 150 quarts of blood every day, removing waste, balancing fluids, and regulating blood pressure. Keeping them healthy comes down to a handful of daily habits: staying hydrated, eating the right amounts of sodium and protein, managing blood pressure and blood sugar, being careful with certain medications, and staying physically active. Here’s how each one works and what the numbers look like.
Drink Enough Fluids, but Not Too Many
Water helps your kidneys flush waste products into urine. When you’re chronically dehydrated, the concentration of minerals and waste in your kidneys rises, which can contribute to kidney stones over time. The general target for healthy adults is about 11.5 cups (2.7 liters) to 15.5 cups (3.7 liters) of total fluid per day, and that includes water from food and other beverages, not just glasses of plain water.
If you’ve had kidney stones or urinary tract infections, you may need more than average. Climate, exercise, and body size all shift the target. A simple check: your urine should be pale yellow most of the day. Dark amber urine usually means you need more fluid.
One important caveat: people with advanced kidney disease sometimes need to restrict fluids rather than increase them, because damaged kidneys can’t remove water efficiently. If you already have a kidney condition, your fluid goals may look very different from the general guidelines above.
Keep Sodium Under Control
Excess sodium raises blood pressure, and high blood pressure is one of the two leading causes of kidney disease. The recommended ceiling for most adults is 2,300 mg of sodium per day, roughly one teaspoon of table salt. The World Health Organization sets the bar even lower at 2,000 mg. For people who are middle-aged, older, Black, or already managing hypertension, U.S. guidelines suggest dropping to 1,500 mg per day.
For people with existing kidney disease who aren’t on dialysis, the National Kidney Foundation recommends staying below 2,400 mg daily. Most of the sodium in a typical diet doesn’t come from the salt shaker. It hides in bread, processed meats, canned soups, frozen meals, and restaurant food. Reading nutrition labels and cooking more meals at home are the two most effective ways to bring sodium down without obsessing over every bite.
Watch Your Protein Intake
Protein generates waste products that your kidneys must filter out. The more protein you eat, the harder they work. For the general population, the recommended daily allowance is 0.83 grams of protein per kilogram of body weight. For a 150-pound (68 kg) person, that works out to about 56 grams per day.
Diets above 1.5 g/kg per day are generally considered high-protein, and people with only one kidney are advised to stay below 1.2 g/kg per day. If your kidneys are healthy, moderate protein intake isn’t dangerous, but consistently very high protein diets (think multiple protein shakes on top of meat-heavy meals) create a sustained workload that may matter over decades. If you have any degree of kidney impairment, keeping protein moderate becomes significantly more important.
Manage Blood Pressure
High blood pressure damages the tiny blood vessels inside your kidneys that do the actual filtering. Over years, that damage reduces kidney function quietly, often without symptoms until it’s advanced. International kidney guidelines now recommend a systolic blood pressure target below 120 mmHg for people with chronic kidney disease, if they can tolerate it. For the general population, staying below 130/80 mmHg is the widely cited goal for protecting both heart and kidneys.
Reducing sodium, maintaining a healthy weight, exercising regularly, limiting alcohol, and managing stress all lower blood pressure. For many people, these changes are enough. Others need medication as well. The key point is that blood pressure control is arguably the single most protective thing you can do for long-term kidney health.
Keep Blood Sugar in a Safe Range
Diabetes is the other leading cause of kidney disease. Chronically elevated blood sugar damages the filtering units inside the kidneys, a condition called diabetic nephropathy. Keeping your HbA1c (a three-month average of blood sugar) below 7% significantly reduces the risk of developing or worsening kidney damage. HbA1c is measured through a routine blood test your doctor can order.
Even if you aren’t diabetic, insulin resistance and prediabetes put extra stress on your kidneys over time. Regular physical activity and a diet that limits refined carbohydrates help keep blood sugar stable for everyone, not just people with a diabetes diagnosis.
Be Careful With Pain Relievers
Over-the-counter anti-inflammatory drugs like ibuprofen and naproxen can reduce blood flow to your kidneys. These medications work by blocking the production of compounds called prostaglandins, which normally keep the small arteries feeding your kidneys relaxed and open. When those compounds are suppressed, the arteries constrict, and less blood reaches the kidney’s filtering units. Occasional use in a healthy person is generally fine, but frequent or long-term use, especially combined with dehydration, can cause acute kidney injury.
Acetaminophen (Tylenol) is generally considered easier on the kidneys for routine pain relief, though it carries its own risks for the liver at high doses. If you rely on pain medication regularly, it’s worth having a conversation about which option makes sense for your situation.
Be Cautious With Supplements
Not all herbal supplements are kidney-safe. Products containing aristolochic acid, found in certain traditional herbal preparations, have been linked to progressive kidney scarring since the early 1990s. High doses of licorice root have caused muscle breakdown that led to acute kidney injury. Creatine supplements, while popular in fitness circles, add to the kidney’s filtering burden in a way that may matter if you already have reduced function.
The bigger issue is that supplements aren’t regulated the same way as prescription drugs, so purity, dosage, and ingredient accuracy can vary widely. If you take herbal products or high-dose vitamins, let your healthcare provider know so they can factor that into any kidney-related lab work.
Stay Physically Active
Regular exercise helps your kidneys indirectly by lowering blood pressure, improving blood sugar control, and maintaining a healthy weight. A study of sedentary older adults found that aerobic exercise at low, moderate, and vigorous intensities (20 minutes on a stationary bike) did not negatively affect kidney filtration rates. In other words, exercise is safe for kidney function and supports the very conditions, like hypertension and diabetes, that damage kidneys the most.
You don’t need an intense routine. Walking briskly for 30 minutes most days, cycling, swimming, or any activity that raises your heart rate provides the cardiovascular benefits that keep your kidneys well-supplied with healthy blood flow.
Know Your Numbers Early
Kidney disease is notoriously silent. Most people don’t feel symptoms until they’ve lost a significant portion of their kidney function. Two simple tests catch problems early. The first is a blood test that estimates your glomerular filtration rate (eGFR), which measures how efficiently your kidneys filter waste. The second is a urine test called the albumin-to-creatinine ratio (UACR), which checks for protein leaking into your urine. A normal UACR is less than 30 mg/g. Anything above that suggests your kidneys’ filters are letting through protein they should be keeping in your blood.
If you have diabetes, high blood pressure, a family history of kidney disease, or you’re over 60, these tests are especially worth requesting at your next routine checkup. Catching early-stage kidney disease gives you the widest range of options for slowing or stopping its progression.