9 Toxins That Can Hurt Your Kidneys (+ How to Avoid Them!)
When you have chronic kidney disease, your kidneys are pretty stressed out. They're not functioning properly, and they're having a hard time keeping up with their main job of filtering water and toxins from your blood. The last thing you want to do is add to the load, but sometimes it can be hard to avoid the sneaky chemicals found in everyday products and food. No need to invest in a bubble suit, though. Our guide will show exactly where to look so you can avoid them as much as possible.
The Toxin: Polychlorinated Biphenyls (PCBs)
What are they? A man-made chemical once used in electrical equipment. It's now banned in the U.S. but is still found in the environment.
Where are they hiding? Farm-raised salmon.
How can I avoid them? Go for wild-caught varieties that have far lower levels. A study in the journal Science found that the PCB concentrations in farm-raised salmon (which are often fed PCB-contaminated fish feed) were on average eight times higher than the concentrations in wild salmon. Over-exposure to PCBs poses risks of reproductive and immunological problems for everyone, but those risks inch higher when you have CKD and your body is unable to flush the toxin from your system. When cooking fish, the Environmental Defense Fund recommends removing the skin, fat, and internal organs where toxins accumulate.
The Toxin: Phosphorus
What is it? A mineral the body uses to help filter waste and repair tissue; toxic in high doses
Where is it hiding? Carbonated drinks
How can I avoid it? With carbonated drinks, phosphoric acid is used to produce the bubbles. But all that fizz might be too much if you have CKD. Here’s why: Your kidneys may already have a hard time removing the excess phosphorus in your blood that comes from the healthy foods you eat; adding even more can lead to diarrhea, weakened bones, and hardening of organs. Instead of pop and sparkling water, experts suggest sipping on antioxidant-packed cranberry juice and flat water. Always keep in mind that anything in excess can be harmful, cranberry juice can potentially cause kidney stones if ingested regularly in large amounts.
The Toxin: Pesticides
What are they? Chemicals that control or kill insects
Where are they hiding? Fruits, vegetables, and bug sprays
How can I avoid them? Some of the produce that has the highest levels of pesticide residue includes strawberries, spinach, apples, and grapes, according to the Environmental Working Group (EWG). Going organic for your fruits and vegetables can help you limit your exposure. If you buy conventional produce, wash and dry it before eating to remove any potential pesticides, and if you have CKD consider using a produce wash for extra assurance. As for bug sprays, stick with natural spritzes and avoid those that contain DEET.
The Toxin: Cadmium
What is it? A toxic metal that is used to make batteries and is ever-present in the environment thanks to industrial dumping (thumbs down)
Where is it hiding? Cigarette smoke; leafy and root vegetables.
How can I avoid it? According to Anis Rehman, M.D., an assistant professor and endocrinologist at Southern Illinois University School of Medicine, cadmium may be found in soil from industrial areas, fuel, and fertilizers. This can, in turn, lead to it being found in leafy and root veggies (it’s absorbed through the soil and the air right into the leaves). Again, washing your produce goes a long way towards lowering cadmium intake.
The Toxin: Phthalates
What are they? Chemicals that makes plastic pliable
Where are they hiding? Plastic wrap, plastic bottles, and plastic food storage containers
How can I avoid them? Not only is buying reusable products good for the environment but, in this case, it can also help your kidneys. Phthalates can leach into the drink or food from the plastic, especially if they’re heated. Swap out your plastic bottle for a thermos or glass water bottle, and buy paper or reusable, non-plastic containers and covers (they even make ones out of beeswax now!). You’ll produce less waste while exposing your body to fewer toxins—it’s a win-win.
The Toxin: Aristolochic Acid
What is it? A family of plant acids associated with kidney problems
Where is it hiding? Asarum (wild ginger) and other herbal supplements
How can I avoid it? While herbal remedies are often thought of as natural and healthy alternatives, you have to be uber-careful when using them and confirm that they contain no aristolochic acid. It's so clearly linked to kidney cancer that the acid has been banned in Europe and Singapore. Kidney failure can occur due to aristolochic acid, causing direct damage to kidney cells as well as nonfunctional scar tissue appearing. If you use herbal remedies or homeopathic medicine, stick to products that have clear ingredients listed and look for the USP seal, which verifies the remedy has the ingredients it claims.
The Toxin: Lead
What is it? A heavy metal that becomes toxic when it builds up in the body
Where is it hiding? Old pipes and paint, gasoline, soil
how can I avoid it? Since lead most often enters the body through breathing or unintentional swallowing (with one exception: gasoline, which can travel through skin), the Mayo Clinic suggests washing hands and toys regularly, removing shoes before entering your house (to avoid tracking in soil with lead), running cold water from your pipes for a minute or so before use, and regularly cleaning dust-attracting surfaces. Houses built before 1978 may have lead-based paint so watch for peeling and crackling, which can release lead dust, according the Environmental Protection Agency.
The Toxin: Mercury
What is it? A toxic metal is found naturally throughout the environment; industrialization increased the amounts in soil and water.
Where is it hiding? Fish (again)
How can I avoid it? All fish have some mercury in them, but big-eye tuna, marlin, and king mackerel contain high levels. While mercury in large amounts is no good for anyone, one study published in the American Journal of Epidemiology found a correlation between mercury exposure and kidney-disease deaths. So, your best bet is to skip these varieties of fish. Instead, consume smaller amounts of mercury-light fish (grouper, snapper, catfish) no more than twice a week.
The Toxin: Copper
What is it? A heavy metal that your body needs—in moderation—to help build tissues
Where is it hiding? Drinking water
How can I avoid it? If your faucet has not been used for more than six hours, run it for a minute before use to remove any copper that may have built up. When you’re cooking or drinking, use cold water as it holds less copper than hot water does. An easy fix is investing in an attachable faucet filter. Just make sure it specifically states that it filters out copper. If it’s already hard for your kidneys to regulate heavy metals in your body, additional copper can be problematic, leading to symptoms of copper poisoning including chills, diarrhea, and jaundice.
- Alcohol Consumption: National Kidney Foundation. (2015). “Alcohol and Your Kidneys.” kidney.org/atoz/content/alcohol
- PCBs in Fish: Environmental Defense Fund. (2013). “PCBs in Fish and Shellfish.” seafood.edf.org/pcbs-fish-and-shellfish
- Tuna Talk: Environmental Defense Fund. (n.d). “Mercury Alert: Is Canned Tuna Safe?.” edf.org/oceans/mercury-alert-canned-tuna-safe
- Medicine with Kidney Disease: Arthritis Foundation. (n.d). “Which Arthritis Medicines Are Safe for Kidneys?” arthritis.org/diseases/more-about/which-arthritis-medicines-are-safe-for-kidneys
- Battery Alternatives: United States Department of Labor. (2019). “Cadmium.” osha.gov/SLTC/cadmium/index.html
- Lead Poisoning: Mayo Clinic. (2019). “Lead Poisoning.” mayoclinic.org/diseases-conditions/lead-poisoning/symptoms-causes/syc-20354717
- Kidney Disease Mortality: American Journal of Epidemiology. (2006). “Kidney Disease Mortality and Enviornmental Exposer to Mercury.” academic.oup.com/aje/article/165/1/72/232535
- PCBs Risks: Harvard Health Publishing. (2004). “Getting your omega-3s vs. avoiding those PCBs.” health.harvard.edu/staying-healthy/getting-your-omega-3s-vs-avoiding-those-pcbsthe-family-healthguide