Generally, three categories of supplements that should be avoided in kidney disease:
Those that increase levels of nutrients that the kidneys have difficulty eliminating
Those that can damage the kidney
Those that can interact with other medications or supplements
What Nutrients Do the Kidneys Have Difficulty Eliminating?
Vitamin A is a fat-soluble vitamin that the kidneys appear to have difficulty removing from the body. It is commonly elevated on blood testing and levels tend to increase further with supplementation. Very high levels can lead to dry skin, painful muscles and joints, fatigue, depression, and may impact the health of the liver. Usually the amount from diet is safe, but adding in additional vitamin A supplementation may be harmful in most types of kidney disease.
Potassium is a mineral that the kidneys can have trouble removing from the body. For certain types of kidney disease, potassium supplements may further increase potassium levels in the body. If potassium levels increase too high this can lead to a condition known as hyperkalemia, which can cause heart palpitations, shortness of breath, chest pain, nausea, or vomiting.
Phosphorus is another mineral that can build up to high levels in those with kidney disease. Usually it is recommended to avoid supplements that contain additional phosphorus. Certain foods may also have additional phosphorus added to them by manufacturers. These include: processed meat, ham, sausages, canned fish, baked goods, cola drinks, and other soft drinks.
What Supplements Can Damage the Kidneys?
Research is still limited in this area, but some studies suggest that those who add more copper into their diet may be at increased risk of further kidney decline. Excessive copper intake can lead to accumulation of copper in the kidney and cause damage to the cells inside the kidney. Copper tends to be an inflammatory mineral. A 2022 study has found that people with the highest intake of copper have been shown to be at increased risk of kidney disease.
There are multiple reports of kidney injury related to chaga mushroom., Mushrooms are sometimes considered by those with kidney disease because some have been found to be helpful, however others have the potential to cause harm.
Some licorice supplements can increase blood pressure and potassium levels and cause injury to the kidneys. However glycyrrhizin is the component inside licorice that causes these side effects and many licorice supplements will remove this component. If it has been removed it should say “deglycyrrhizinated”.
What Supplements Interact with Medications?
There are many interactions that can occur with medications and it would be difficult to summarize all of them here. Side effects may be more common in those who combine certain supplements with medications. In other cases there can be supplements that have additive effects. For example, a person on blood pressure medication who takes a supplement that lowers blood pressure as well may have their blood pressure go too low. This could lead to dizziness or fainting. Sometimes additive effects can be wanted and helpful, however this should be done with careful monitoring under the care of a health professional.
Kidney disease is complex and the kidneys are more sensitive when their function has been compromised. Many supplements that would normally be safe for someone with healthy kidneys are no longer as safe when kidney function is already decreased. This article summarizes just a small number of supplements that should be avoided in kidney disease; in fact there are over 100 different supplements that may cause or progress kidney disease and should likely be avoided in those at risk for or with established kidney disease. It is important to know which therapies and supplements can be harmful before considering any options for kidney support. At the same time, there are also over 70 natural options that have been shown in clinical studies to help heal the kidneys rather than harm. Dr. Baker (ND) chooses natural therapies that have demonstrated the highest level of safety and benefit in research. He also checks each therapy he uses for safety alongside every medication a patient is using, with a database of 100+ research journals that assesses for over 20,000 interactions. If you are looking for a naturopath that has significant awareness of kidney health and safety, please reach out.
 Association of copper exposure with prevalence of chronic kidney disease in older adults
Author links open overlay panelFanjia Guo a, Yaoyao Lin b, Lin Meng b, Lihe Peng c, Huafang Zhang d, Xue Zhang c, Mingjuan Jin a, Jianbing Wang e, Yongming Zhang f, Mengling Tang b, Kun Chen a. Link