The benign blemish on your lip that DOUBLES your risk of dementia

They’re uncomfortable, embarrassing, and difficult to get rid of, but cold sores can also be a warning sign of dementia.

Swedish scientists have published a paper linking the virus that causes cold sores, herpes simplex virus-1 (HSV-1), to an increased risk of a disease that destroys memory.

By studying more than 1,000 older adults over a 15-year period, researchers found that people infected with HSV-1 were twice as likely to develop dementia as those who were not infected.

Scientists aren’t sure why the two conditions may be linked, but it may be because they lurk in your nervous system for life.

At any time, flare-ups can occur, which can cause inflammation within the nervous system, pressing on and damaging the delicate tissues of the nervous system and brain.

The theory is that over time this could lead to some of the changes associated with dementia, such as memory loss, breakdown of brain tissue and confusion.

This is just the latest in a series of articles investigating the link between common viruses and the risk of dementia later in life.

Recently, scientists have also linked the varicella-zoster virus, which causes chickenpox and shingles, to changes in brain health.

Still, experts say the evidence is mixed and other studies have found no link between the virus and cognitive decline.

HSV-1 affects between 50 and 80 percent of American adults, according to Johns Hopkins. This virus is similar, but not identical, to the virus that causes the herpes STD, called HSV-2.

The virus is spread primarily through intimate person-to-person contact, such as kissing or oral sex, although in rare cases it can be spread through sharing drinks.

It can also be passed from mother to child in the womb and cause serious side effects in children.

Once a person catches the disease, many symptoms are manageable and mild. Early signs include fever, swollen lymph nodes, sore throat, and sores inside the mouth and gums.

After the initial flare-up, symptoms may disappear completely, before periodically appearing on the side of the mouth or lip as a red, ulcerative sore.

During one of these flare-ups, doctors may prescribe antiviral medications or ointment to relieve discomfort or have patients take over-the-counter pain relievers like ibuprofen to manage the inflammation.

For a long time, doctors thought this unsightly visitor was one of the only lingering effects of the disease.

However, in recent years, a more worrying link has emerged.

This is particularly the case of the team of researchers from Uppsala University, who published their results in December 2023 in the Journal of Alzheimer’s Disease.

Their study followed 1,002 Swedes, 80 percent of whom were HSV-1 carriers, aged over 70 for 15 years.

They adjusted for factors such as education level and genetic predisposition to Alzheimer’s disease.

By the end of the study, 32 subjects had developed Alzheimer’s disease and 63 percent had developed another form of dementia – making up a total of 11 percent of participants. Eighty-nine percent of these people had herpes.

The researchers then compared these people to the rest of the group, which had not developed dementia by the end of the study, and in which 82% of participants had herpes.

After adjusting for some factors that may have affected the data, they concluded that those who contracted herpes were twice as likely to have developed some form of neurodegeneration.

They note that their limitations include that they could not adjust for the effect that age might have on the data, nor exclude other factors like medications, heart disease and diabetes.

In the United States, an estimated 4% of adults over the age of 65 have dementia. For comparison, Johns Hopkins experts estimate that between 50 and 80 percent of the population has HSV-1.

Their article is not the first to link the two.

A 2024 study by South Korean researchers using data from a national health insurance service including more than 750,000 people found that people with HSV and varicella-zoster virus (VSV) were more susceptible to develop dementia.

However, not all studies looking at these two factors have found a link. A 2019 study from several universities in the United Kingdom found that the link between dementia and HSV-1 was inconclusive and did not establish a strong association.

Dr. Jagan PillaI, a cognitive neurologist at the Cleveland Clinic, told Parade that studies aren’t convincing enough to conclude that herpes could cause dementia. Of the 2019 UK study, he said: “It supports the need for higher quality future studies.”

Additionally, Dr. Monica Gandhi, an infectious disease specialist at UC San Francisco, told Medical News Today that rates of herpes infections in general are much higher than rates of dementia.

This difference, she says, is evidence that they might not be related.

She said: “Given how common herpes virus infection is among young people, I wouldn’t let this study worry you unduly.”