The information that I am about to bring you is bound to raise some eyebrows. Why? Because, unbelievably, after years of research, scientists are finding that there might be a simple way to prevent Alzheimer’s disease. Researchers have been trying to understand the cause and progression of Alzheimer’s for decades—and it would be incredible if doctors actually could do something to slow the progression of this debilitating disease.

There’s growing evidence that Alzheimer’s may be caused by the herpes simplex virus 1 (HSV1), the same virus that causes fever blisters or cold sores on the face and mouth. (It is not believed to be caused by the other herpes simplex virus—HSV2, genital herpes, which is transmitted sexually.) HSV1 attacks the immune system, particularly the peripheral nervous system. Once it has attacked, it never leaves the body but lies dormant and occasionally reactivates, causing a flare-up of blisters or enlarged lymph nodes, especially when set off by a trigger, such as stress or fatigue.

Research shows that HSV1 also can infect the brain—and that flare-ups of HSV1 in the brain may be a primary cause of the brain damage associated with Alzheimer’s. This means that it may be possible to take steps to stave off Alzheimer’s by suppressing HSV1. To learn more about preventing Alzheimer’s, our editors turned to David Perlmutter, MD, an integrative neurologist and a pioneer in brain health.

According to Dr. Perlmutter, the HSV1 research, which is ongoing, is so compelling that for the past year, he has been employing the new HSV1 theory with his patients who are at risk for Alzheimer’s—including those with parents who had the disease and those who have had a decline in cognitive function themselves. I also have started using Dr. Perlmutter’s protocol with my own patients. Here’s what he has to say…


For a long time, most Alzheimer’s researchers focused their attention on a sticky protein or plaque, beta-amyloid, in the brains of patients with Alzheimer’s. There seemed to be a correlation between the amount of this protein and the amount of cognitive impairment. The thinking was that if you could get rid of this protein, you could get rid of the disease.

But in a 2010 study published in PLoS One, Harvard researchers and other colleagues demonstrated that beta-amyloid could have a protective role, functioning in the immune system as an antimicrobial that attacks and destroys bacteria and viruses in the brain.

Studies focusing on HSV1 and Alzheimer’s have been going on for nearly three decades. But new discoveries about genetics and genetic predispositions are inspiring researchers to clarify the link between the virus and Alzheimer’s.

While it isn’t known how many people with Alzheimer’s have HSV1, Dr. Perlmutter believes that most people are HSV1-positive. This doesn’t mean that everyone who is HSV1-positive will get Alzheimer’s—it means that people who have a genetic susceptibility to Alzheimer’s who also have HSV1 (that periodically reactivates causing symptoms such as fever blisters) might be more at risk for the disease. In 2008, Ruth Itzhaki, PhD, from the University of Manchester in England, estimated that 90% of adults have an HSV1 infection in areas of the brain affected by Alzheimer’s.

In 2009, Dr. Itzhaki published a study in Journal of Pathology showing that in Alzheimer’s patients, more than 70% of the HSV1 virus’s DNA was located inside beta-amyloid plaques. It appears as though plaque is used by the immune system to keep the virus in check.

While HSV1 infection of the brain may be latent much of the time, stress and other triggers, combined with a genetic susceptibility to Alzheimer’s, might cause it to flare up (just as it does with HSV1-related cold sores and fever blisters), leading to inflammation in the brain.


When my patients have a family history of Alzheimer’s (for example, a parent with the disease), I recommend that they get a blood test to determine if they have active HSV1. Patients who do not have a family history of the disease but want to know if they have active HSV1 also are encouraged to get tested.

Dr. Perlmutter and I use a standard viral test. We test for two antibodies produced when the body fights an infection—immunoglobulin G (IgG) and immunoglobulin M (IgM). There are no rules about the way these tests work—IgM is produced more quickly following an infection, but this varies by person. Specific IgG antibodies can indicate the HSV1 virus, but the time this takes to be detectable varies. So a test for both antibodies is given—and the following regimen is recommended if either antibody is high.


Dr. Perlmutter reports that many of his patients who have Alzheimer’s and follow the protocol show no further signs of cognitive decline and actually regain some cognitive function. Since Alzheimer’s is such a devastating illness—and the protocol uses largely safe and natural remedies—I think it’s wise for patients with cognitive decline and/or a family history of the disease to take these steps to suppress the virus.

The protocol includes the following supplements and one prescribed medication. All the supplements are available at health-food stores and online. They are safe for everyone.

Lysine. This essential amino acid has been shown in studies to prevent outbreaks of cold sores caused by HSV1. It also seems to prevent outbreaks of HSV1-related inflammation in the brain. Lysine works by blocking the activity of arginine, another amino acid that HSV1 needs in order to reproduce. Dose: 500 milligrams (mg), three times a day.

Vitamin D. This vitamin has been found to prevent HSV1 activity—not by killing HSV1 but by rendering it dormant. Patients need to have their vitamin D blood levels tested regularly to ensure that they have blood levels of between 70 ng/mL and 80 ng/mL. Your doctor will tell you how much you need daily.

Curcumin. The active ingredient in turmeric, this spice gives curry its color and much of its flavor. It inhibits HSV1 activity. Dose: 200 mg to 400 mg of turmeric extract containing 95% curcuminoids daily.

Antiviral treatment. Dr. Perlmutter recommends that patients whose blood tests show active infection with HSV1 take a daily 500-mg dose of the antiviral drug valacyclovir (Valtrex), commonly used to prevent HSV1 from spreading. This medication, which is available by doctor’s prescription only, does not produce harmful side effects and can be taken for long periods of time. Dr. Perlmutter recommends that it be used on an ongoing basis, similar to the way other drugs (such as blood thinners) are prescribed.

Unlike Dr. Perlmutter, before prescribing Valtrex, I first provide patients with other antiviral treatments, such as intravenous (IV) vitamin C, IV and oral glutathione (a powerful antioxidant) and astragalus, which increases the body’s resistance to stress and disease. I do recommend Valtrex to patients whose antibody levels are not decreased by the natural therapies. If you are interested in this protocol, speak to a holistic doctor about it.

Since HSV1 stays in the body permanently once a person is infected, our thinking now is that people who want to prevent Alzheimer’s need to continue this protocol for the rest of their lives. To check that the therapy is reducing HSV1, patients’ antibody levels are retested annually.