The early stages of chronic kidney disease (CKD) cause no symptoms. In fact, 90% of people with the condition don’t know they have it. But even if your kidneys are still healthy—so far—you could be doing things that harm them without realizing it. 

Kidneys are critical to the health of the whole body. They filter waste, balance body fluids, maintain blood pressure, control the production of red blood cells and regulate electrolytes and minerals, such as potassium, sodium and magnesium. When kidney health declines, waste builds up and causes health issues—including high blood pressure, anemia and metabolic bone disease (such as osteoporosis). The final stage is kidney failure and the need for regular dialysis or a kidney transplant.

The Greatest Danger

More than 10% of Americans—30 million adults—have CKD, which is the ninth-leading cause of death in the US, according to the CDC. One factor that drives the prevalence of this disease is that people who are at risk often don’t realize it…so they’re less likely to get tested…take necessary precautions to protect their kidneys from further damage…and/or take steps to reverse early stages of damage. 

People with diabetes and high blood pressure are at especially high risk. Together, these two conditions are responsible for two-thirds of CKD. Other risk factors include age (being 60 or older)…having a family history of kidney failure…being of non-Caucasian descent (African-American, Hispanic, Asian, Pacific Islander and/or Native American)…obesity…lupus…and cancer.

If you have risk factors for CKD, you should be tested with a Kidney Profile annually. The profile combines a urine albumin-to-creatinine ratio (ACR) test and an estimated glomerular filtration rate (eGFR) blood test. 

The Threat from the Drugstore

Healthy kidneys are able to filter out medications and supplements without harm to the kidneys themselves. However, drugs and supplements can cause kidney damage or other side effects. If you take any of these worst offenders, check with your clinician and be sure to get an annual Kidney Profile…

• Nonsteroidal anti-inflammatory drugs (NSAIDs). The kidney danger from long-term use of NSAIDs, such as ibuprofen (Advil, Motrin) and naproxen (Aleve), is well-known, but few people realize how easy it is to do harm. A recent large study published in JAMA Network Open that looked at nearly 800,000 active young and middle-aged adults found that using eight or more doses a month put them at a 20% higher risk for kidney damage compared with not taking any NSAIDs. 

• Proton pump inhibitors (PPIs). Heartburn/reflux/GERD drugs such as omeprazole (Prilosec), esomeprazole (Nexium) and lansoprazole (Prevacid) pose a risk to the kidneys if taken long-term. A recent study published in Scientific Reports found that compared with people who took other antacids, those who took PPIs (including over-the-counter versions) were 28.4% more likely to develop CKD.

• Herbal and dietary supplements. Since supplements are not regulated in the US, there is no guarantee that ingredients and amounts listed on a supplement label are what is actually in the bottle. Even if the label is accurate, “natural” herbs and supplements can be toxic to the kidneys, especially in large amounts. 

For instance, kidney injuries have been reported from using the herbs Chinese yew extract, St. John’s wort and wormwood. Talk to your doctor about the health risks of any herbal and/or dietary supplements you take—ideally, before you use them. 

• Prescription medications. Patients who know they have CKD with decreased kidney function should make sure all their doctors are aware of this. Dosages for some drugs may need to be adjusted for these patients—and some medications, such as metformin (Glucophage), used to treat diabetes, and the muscle relaxant baclofen (Lioresal), may need to be avoided. But people who don’t know that they have CKD are in danger of getting harmful dosages of certain drugs, including beta-blockers used to treat high blood pressure…antimicrobials…antifungals…and insulin. 

Kidney-Compromising Lifestyle

Lifestyle factors also can damage kidneys…

• Insomnia. Chronic insomnia has been associated with kidney damage. One study of more than one million veterans found that insomniacs were 2.4 times more likely to develop kidney failure than those who slept normally. Poor sleep is linked to high blood pressure and vascular disease, which may in turn lead to kidney disease. People who already have CKD also are at higher risk for sleep disorders, such as sleep apnea and restless legs syndrome.

• Too much protein. Low-carb diets that emphasize fat and protein, such as Keto or Paleo, may jeopardize the health of people at risk for CKD—particularly if they heavily consume processed red meats. White meat, fish and dairy protein do not seem to carry the same risk. Vegetable proteins may actually be protective. The research as to whether excessive amounts of protein also are harmful for people who aren’t at increased risk for CKD is not conclusive. 

• Processed foods and phosphorus. Our bodies need some phosphorus for strong bones, and healthy kidneys are able to remove any excess so that toxic amounts don’t build up in the body. However, not all phosphorus is the same. 

Organic phosphorus occurs naturally in many protein-rich animal and plant foods and is only up to 60% absorbed by the body. There is little danger of consuming too much plant-based phosphorus, as long as the kidneys are healthy. Inorganic phosphorus is an additive used to improve the shelf life and/or color of processed foods, such as processed cheese and sodas. Inorganic phosphorus is more than 90% absorbed…and too much can easily accumulate in the body. Excessive phosphorus throws off the body’s delicate calcium balance. It can lead to calcium being drawn from the bones and dangerous deposits of calcium accumulating in blood vessels, the lungs, the eyes and the heart. Because our diet is so heavily processed, most of us get up to twice the recommended dietary allowance of 700 mg/day for adults. Check the ingredients list before buying packaged foods—phosphorus additives have “phos” in the name. Or better yet, stick to whole, fresh foods. 

• Air pollution. A major study of almost 2.5 million veterans published in Journal of the American Society of Nephrology estimated that air pollution causes nearly 45,000 new cases of CKD in the US each year. Other research compared county levels of air pollution with the incidence of CKD among one million Medicare patients. The researchers found that diagnoses of CKD were highest in counties that had the highest levels of air pollution. Air pollution as a cause of CKD is being studied further. But for the time being, it makes sense to avoid or limit exposure as much as possible. 

Should You Worry About Antiperspirants?

You may have noticed an FDA warning for people with kidney disease on labels of antiperspirants. Antiperspirants contain small amounts of aluminum, which temporarily plug sweat ducts to reduce perspiration. Excessive amounts of aluminum can be toxic. However, the amount of aluminum that is absorbed by the skin from anti­perspirants is tiny—­especially compared with the amount of aluminum people are exposed to naturally from water and soil. Recommended: If you have kidney disease, ask your doctor if you should stick with plain deodorants that don’t contain aluminum.