Why It's Not Safe To Use Saliva as a Lubricant During Sex

Saliva may seem like a harmless swap for your own natural lubrication or the store-bought kind—it's always accessible if you need it.

"When they don't have lube on hand, I've had patients tell me that they use saliva," Felice Gersh, MD, author of PCOS SOS: A Gynecologist's Lifeline to Naturally Restore Your Rhythms, Hormones, and Happiness, told Health.

There have even been individuals who prefer to use saliva over lubricants, according to a review of studies on lubricant use published in 2022 in Sexual and Reproductive Health Matters.

However, saliva is not considered to be a good alternative to use during vaginal or anal sex if you or your partner don't have any lubricants on hand—and here are some reasons why.

Sexually Transmitted Infections Can Be Transmitted Through Saliva

Using saliva can increase the risk of transmitting sexually transmitted infections (STIs) between partners. "Any STI in the throat or mouth can be transmitted to the genitals through saliva," Dr. Gersh explained.

For example, a person with herpes can transmit the STI to their partner during vaginal, anal, or oral sex. Two of the ways genital herpes transmission might occur include having contact with the saliva or skin in the oral area of someone with an oral herpes infection.

Thus, if an individual or their partner had an active herpes lesion, using saliva for lubrication could lead to the transmission of genital herpes.

Even if you don't see a cold sore on or around a person's mouth, the virus can still be transmissible. "Herpes can present with blisters or sores, but it can also present asymptomatically," Dr. Gersh added.

Herpes isn't the only oral STI you could contract. "Gonorrhea, chlamydia, HPV, syphilis, and trichomoniasis can also all be transmitted to the genitals through saliva," Dr. Gersh explained. And like herpes, these infections may not have any symptoms.

You Can Get a Vaginal Infection or Irritation

"The bacteria in saliva are very different than the bacteria in your vagina," Dr. Gersh said. Saliva also contains digestive enzymes that break down food. When you introduce these bacteria and enzymes into your vagina, the result can upset your vaginal microbiome and leave you susceptible to developing a yeast infection or bacterial vaginosis, Dr. Gersh explained.

Both of these curable infections develop when the balance of yeast and bacteria that naturally exist in the vagina is thrown off. "Using saliva as lube provides a perfect storm to alter the vaginal ecosystem enough to trigger one of these infections," Dr. Gersh said.

In addition, saliva can sometimes set off a process of inflammation that leads to itching and burning, according to a bulletin published in 2020 in the journal Obstetrics and Gynecology.

Saliva Does Not Have the Qualities of a Lubricant

Even if you remove the risk of contracting an STI or vaginal infection, saliva is still not advised. "It has no innate qualities that would make it a good lubricant," Dr. Gersh said. "It doesn't have the slippery consistency, it evaporates and dries more quickly, and further, it's irritating."

Personal lubricants, on the other hand, are designed to create slickness that's very similar to the lubrication your own body produces. "Lubricity creates a 'glidey' feel, which helps to decrease friction," Dr. Gersh said.

Friction can cause small nicks or tears in the vagina or the anus, which, besides being painful, might allow harmful microbes into the body—something you definitely don't want.

The bottom line: "99.9% of people have probably used spit as lube with a partner at some point, but it is not the best or safest choice," Dr. Gersh advised. Consider that a reason to stock up on water- or silicone-based personal lubricants so you'll be prepared whenever the mood strikes.

A Quick Review

Though saliva may always be available to you, it shouldn't be used as a lubricant during sexual activity. It's possible for STIs, such as herpes or syphilis, to be transmitted through saliva, and saliva can lead to vaginal infections or irritation.

Furthermore, saliva does not have the same properties as a lubricant because it dries more quickly than lubricants and is less slick. Therefore, it's best to have lubricants on hand (made with water or silicone) to use instead of saliva.