A category where foods can carry real risks as well as benefits — oxalate load and potassium content matter for some people, and those caveats are recorded on the food pages.
Kidney function, stone risk and urinary tract health.
6 foods, grouped by the strongest rating any of its claims in this area reaches. Ratings describe the research, not the food. How ratings are decided.
Early human work, or mostly lab and animal research.
Not enough human research to say anything useful yet.
Asparagus officinalis
The young shoots of a perennial lily relative, harvested in spring. White asparagus is the same plant grown covered so the spears…
Kidney and urinary function: Asparagus has a long reputation as a kidney-cleansing and diuretic food. There is no dependable human research showing it changes kidney function or urinary outcomes, and the healthy kidney does not require dietary assistance to filter blood.
Apium graveolens
The fibrous leaf stalks of a cultivated umbellifer, eaten raw or used as an aromatic base in cooking. It is mostly water by…
Kidney and urinary function: Celery juice is promoted for cleansing the kidneys and clearing the body of unwanted substances. No dependable human research supports any of that, and the kidneys and liver already perform those functions without dietary help.
Coriandrum sativum
The fresh leaf of Coriandrum sativum, the same plant that yields coriander seed. A well-documented genetic variation in olfactory…
Kidney and urinary function: Cilantro is heavily promoted as a way to clear heavy metals from the body, often alongside chlorella. The claim rests on laboratory and rodent work; controlled human research does not support it, and people with genuine heavy metal exposure need medical assessment rather than a smoothie ingredient.
Cocos nucifera
The clear liquid from inside a young green coconut, distinct from coconut milk, which is pressed from the mature flesh. It is a…
Kidney and urinary function: Coconut water is widely recommended online for kidney stones. A couple of very small studies have looked at urinary chemistry after drinking it, which is nowhere near enough to support the recommendation, and the potassium load makes it a poor idea for some people with kidney disease.
Petroselinum crispum
A biennial Apiaceae herb eaten fresh in quantity in dishes such as tabbouleh and used as a garnish elsewhere. It is unusually…
Kidney and urinary function: Parsley is a traditional diuretic and is sold in teas marketed for kidney cleansing. There is no dependable human research behind those products, and people with kidney disease have specific reasons to be cautious with concentrated herbal preparations.