The fish pedicure is a popular spa treatment in which a person immerses their feet into a basin of Garra rufa doctor fish to have them nibble off dead skin. But this beauty trend is not without risks.
In a case report in JAMA Dermatology, a woman with undiagnosed type 2 diabetes experienced nail discoloration and onychomadesis following a fish pedicure. This condition causes nails to thin and eventually fall off.
What is a fish pedicure?
A fish pedicure, also known as ichthyotherapy, is an alternative to a traditional manicure or pedicure. It involves soaking feet in a tub of water filled with Garra rufa, a type of fish commonly known as “doctor fish.” The fish eat the dead skin on the feet and supposedly leave the feet smooth and free of calluses. Fish pedicures are also sometimes used to treat skin conditions such as psoriasis.
While Garra rufa typically feed on plankton and algae, they will eat dead skin when there is nothing else available. This is especially true in natural hot springs where Garra rufa live and thrive on the sloughed skin of visitors. In fact, several cases of cutaneous infection have been attributed to ichthyotherapy, including one case of methicillin-resistant S. aureus that required two weeks of cotrimoxazole and rifampin treatment [1, 2].
Unfortunately, because it is difficult or impractical to disinfect the tanks used for fish pedicures, salons often reuse the same Garra rufa with each new client. This practice increases the risk of infection as bacteria (including Streptococcus agalactiae group B and Mycobacterium marinum) are spread from one foot to another via the shared fish. Garra rufa are not native to North America and must be imported from other parts of the world, making them susceptible to disease and stress in transit.
How does a fish pedicure work?
The idea behind the fish pedicure (also known as ichthyotherapy) is to use tiny toothless fish called Garra rufa, also called doctor fish, to eat away dead skin. People essentially soak their feet in a water basin filled with these fish, and the fish nibble at the dead skin that naturally accumulates on the person’s foot.
The treatment may help reduce calluses and exfoliate dry skin, and some research suggests it could minimize symptoms of psoriasis. However, the risks of a fish pedicure are significant and include the possibility of infection. The fish used in this type of treatment are often imported from Asia, and many die during the long journey to salons. This can result in salons using the same fish on multiple patrons, increasing the risk of spread of disease. A 2011 study of Garra rufa fish in an ichthyotherapy spa found that the fish were infected with Streptococcus agalactiae, which can cause septicemia in humans.
In addition, the dentist fish don’t always have discretion when it comes to eating human skin. Garra rufa are omnivorous and typically feed on phytoplankton and zooplankton, but they will nibble at any dead skin they come across, including the cuticle of the nail. This makes the treatment more dangerous, especially for those with preexisting health conditions like diabetes that can increase susceptibility to infections.
What are the risks of a fish pedicure?
A fish pedicure involves placing your feet in a basin of water while minute, toothless carp-like Garra rufa fish nibble away at your dead skin. Those who favor the treatment claim that Garra rufa soften calluses and help lighten dark cuticles. But, according to a report from the Health Protection Agency (HPA), fish spas can also pose health risks.
The HPA recommends that people with conditions that raise infection risk such as diabetes and those who use drugs that suppress the immune system avoid this procedure. The fish in these spas may also carry harmful bacteria. A 2011 European study found that Garra rufa destined for salons tested positive for the bacteria Streptococcus Agalactaie group B, which can cause serious infections.
In addition, the HPA warns that Garra rufa are omnivorous and will only eat human skin if they can’t find other sources of food. In natural settings, such as a hot spring, the fish are typically fed plankton. But, because Garra rufa are starved in spas, they will look for other edible options like dead skin.
There have been reports of cutaneous infections associated with Garra rufa-induced pedicures. One such case, reported by Grassberger and Hoch, involved onychomadesis—a condition that stops nail plates from growing, resulting in thickened nails. In the case of this patient, her undiagnosed diabetes and ichthyotherapy (fish pedicure) were the likely causes of her bacterial nail infection.
What are the benefits of a fish pedicure?
While some people find that fish pedicures help their feet look and feel softer, others do not. Those with chronic conditions that affect the feet—like diabetes, vascular disease or poor circulation—should not get fish pedicures. And anyone with a compromised immune system, such as HIV or cancer, should not do them either.
There are other concerns, too. A study published in 2019 noted that zoonotic diseases—those that can be transferred from animals to humans—are a risk with these types of treatments. It also pointed to studies that indicate the presence of bacteria, like Streptococcus agalactiae, in G. rufa fish that have been used in pedicures, as well as in salons where these treatments have been offered.
It’s hard to maintain sanitary conditions with these treatments, which are often offered in nail salons that aren’t required by cosmetology laws to sanitize the foot basins between customers. In addition, the type of fish used for these treatments is not native to North America and can deplete local waterways if it is overfarmed.
The fish that are used for these treatments can also bite people, which could lead to infections and pain. In addition, some people find the sensation of being nibbled by these toothless fish uncomfortable or ticklish. And there are many other safe, effective options for treating dead skin on the feet, such as scrubbing and exfoliating.