Kidney Health Vectors by Vecteezy

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Q: I keep hearing we should sit less. But what’s the evidence that it makes a difference, and how should you go about doing it?

A: That’s an important question because whenever you make any type of lifestyle change, it’s helpful to know not just what you’re adding but also what you’re subtracting. For example, when people eat more fruit, they may eat fewer cookies, and both shifts are beneficial. Likewise, people are better off when they move more and sit less.

A study published in the European Heart Journal in November 2023 provided estimates about the potential advantages of choosing different activities — including sleeping — in place of sitting. The article included data from more than 15,000 people. Their average age was 54, nearly 55% were women, and most (88%) rated their health as good or better.

Researchers assessed the participants’ heart health based on their BMI (a measurement that incorporates both weight and height), waist circumference, cholesterol and triglyceride levels, and HbA1c (a measure of blood sugar used to assess diabetes risk). About a third were taking medication to control cholesterol, high blood pressure or diabetes, and about 10% had been diagnosed with heart disease.

Participants wore special activity monitors that attach to the front of the thigh. These monitors are more accurate than those worn on the hip or the wrist for discerning between sitting and standing.

Based on a week’s worth of data, the average participant’s day consisted of 7.7 hours sleeping, 10.4 hours sitting, 3.1 hours standing, 1.5 hours doing light physical activity, and 1.3 hours doing moderate-to-vigorous physical activity.

Not surprisingly, researchers found that moderate-to-vigorous activity proved most beneficial for heart health, while sitting was the worst. Next, they created statistical models to estimate what would happen if a person swapped one behavior for another.

Replacing even just five minutes of sitting with moderate-to-vigorous activity (such as brisk walking, running or cycling) could have a tangible effect on heart health, they reported.

While adding longer, more intense bouts of exercise can reap greater rewards, even small, modest changes can make a difference. For instance, replacing sitting with standing led to positive changes across all the health parameters.

While the researchers’ model suggests that even sleeping is better than sitting when it comes to heart health, it’s not quite that simple. For example, indirect factors that lead to weight gain (for example, snacking while watching television) may explain why sitting appears worse than sleeping.

Your smartphone, a fitness band or smart watch can help you keep tabs on your daily activity. Some models include default reminders to stand up at least once an hour for at least 12 hours per day.

Q: My blood test showed a slightly high blood creatinine level. What are some natural ways I can help keep my kidneys healthy?

A: Doctors use a blood creatinine level to assess kidney function. Creatinine is released from muscle cells into the bloodstream. Creatinine is one of the things that the kidneys filter from the blood. If the kidneys start to lose some function, blood creatinine level rises.

This minor reduction in kidney function may be temporary. But even if it is permanent, there’s a lot you can do now to slow and even prevent future damage.

Keep blood pressure well controlled. High blood pressure is a major contributor to kidney disease progression and can damage the kidney’s filters and small blood vessels.

Control blood sugar levels. Slightly elevated blood sugar levels often mean a person has prediabetes, a precursor for Type 2 diabetes. Diabetes is the top cause of chronic kidney disease because persistent excess sugar exposure damages tiny blood vessels in the kidney.

Reduce salt. The sodium in salt can cause your body to retain fluid, and excess sodium raises blood pressure in many people. The Dietary Guidelines for Americans recommend limiting sodium intake to less than 2,300 milligrams per day.

Limit alcohol intake. Don’t have more than one drink per day. Regular excessive alcohol drinking increases the risk for high blood pressure, contributes to weight gain and makes the kidneys work harder.

Lose weight if you need to. Obesity makes the kidneys work harder than they need to. This can ultimately cause the kidney filters to break down.

Stop smoking. Smoking damages blood vessels, including those providing oxygen and nutrients to the kidneys.

Exercise regularly. Aerobic exercise — the kind that makes your heart and lungs work hard, like brisk walking — helps blood vessels stay healthy, flexible and able to expand and contract well.

Stay hydrated. Getting enough fluids each day — from water or watery foods like fruit and soup — helps the kidneys flush out toxins from the body.

Limit painkillers. High doses of nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil, Motrin) and naproxen (Aleve), can cause kidney damage and worsen existing kidney disease. Follow the dosing directions carefully.

Watch your protein intake. Too much protein forces the kidneys to work overtime. Whether a high-protein diet actually causes kidney damage is hotly debated. Still, it’s safest to stick closer to a standard protein intake of about 0.36 grams per pound of body weight.

Howard LeWine, M.D., is an internist at Brigham and Women’s Hospital in Boston and assistant professor at Harvard Medical School. For additional consumer health information, please visit health.harvard.edu.

© 2025 Harvard University. Distributed by Tribune Content Agency, LLC.