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Key takeaways:
- Cold sores are caused by the herpes simplex virus (HSV).
- Less than half of people with HSV will get cold sores from the virus.
- Genetics plays a role in who will get cold sores, and environmental factors can trigger their occurrence.
Members will see their genotype report below and the solutions in the Lifehacks section. Consider joining today.What causes cold sores?
There are two types of herpes simplex virus: HSV-1 and HSV-2. Cold sores are usually caused by HSV-1, while HSV-2 usually causes genital herpes. But either type of HSV can cause either condition.
Herpes Simplex Virus PMC8923070 Once the herpes simplex virus enters your body, it stays for life. It hides in nerve cells and can become active again later, causing another outbreak of cold sores.
Cold sores are highly contagious and can be easily spread through close contact, such as kissing or sharing utensils. If you have a cold sore, it’s important to avoid close contact with others, especially newborns, and to wash your hands frequently to prevent spreading the virus.
Using DNA from people who lived in the Bronze Age, researchers now think that HSV-1 has been making the rounds in humans for around 5,000 years.[ref]
Science of cold sores
Cold sores are also called herpes simplex labialis or fever blisters.
About 60%-80% of the population is seropositive for HSV1, but only around 20%-30% of the population will ever get cold sores. Some people get a cold sore rarely (once or twice a decade), while others may have monthly outbreaks.[ref][ref]
The sores that form on the outside or inside of the lip are uncomfortable — and embarrassing for some people. Who wants an open sore or big scab on their lip…
Typically, cold sores form when the HSV virus is actively replicating. Often, people notice tingling or burning in the affected area before the development of the sore. Rupturing of the blister that forms will lead to a scab.[ref]
Why does this happen? The virus infects nerves around the mouth and remains latent in the nucleus of neurons, undetected by your immune system. When reactivated, the virus creates new infectious particles that move down the neuron to the skin, causing the sores.
Interestingly, the latent virus is thought to enhance the survival of the infected cells.
What causes the reactivation of the virus?
Triggers of HSV reactivation include:[ref]
- stress, which can alter immune response
- ultraviolet (UV) radiation (sunburn)
- temperature fluctuations (cold, wind, heat)
- surgical trauma or dental procedures
- immunotherapy that suppresses the immune response
- hormonal changes
Researchers find that HSV-1 reactivates in the trigeminal nerve when the immune system is suppressed, such as during times of stress or when fighting off another infection.
Trigeminal nerve illustration. (Public domain) Why doesn’t everyone with HSV get cold sores?
This is a question that researchers have been trying to answer for decades.
Genetics is at least part of the answer as to why not everyone gets cold sores. The strain of the herpes simplex virus may play a role as well. Additionally, an external stressor such as wind, sunburn, or oral surgery may need to be involved for some to activate the virus.[ref][ref]
Keep in mind that not everyone gets the herpes simplex virus. Transmission of the virus is usually through skin contact and is more likely if there is slight damage to the surface of the skin.[ref] Additionally, genetic variants in the immune response genes may protect some individuals from ever getting the virus.[ref]
Cold Sores Genotype Report
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Lifehacks: Cold Sore Solutions
Talk with your doctor about the pros and cons of prescription-based antiviral medications for cold sores.
Natural treatments for cold sores
Lemon balm (Melissa officinalis):
A placebo-controlled clinical trial showed that a cream containing 1% extract from lemon balm was effective for reducing symptom scores by day 2. The cream was applied four times a day for five days.[ref]Gene-Eden-VIR/Novirin:
This is a patented herbal treatment that has undergone clinical trials to determine its efficacy against cold sores. One trial showed that it cut outbreaks in half. The formula includes a ” 100 mg extract of quercetin, a 150 mg extract of green tea, a 50 mg extract of cinnamon, a 25 mg extract of licorice, and 100 μg of selenium”.[ref]Myricetin:
A natural flavonoid available as a supplement, myricetin has been shown in several studies to have antiviral effects against HSV-1 and HSV-2. Dihydromyricetin is another form of myricetin (also with antiviral properties).[ref] You can find myricetin as a supplement in health food stores and online.Quercetin:
Another natural flavonoid, quercetin has been shown in cell studies to lower HSV infectivity.[ref]Related article: Quercetin: Scientific Studies + Genetic Connections
Resveratrol:
Resveratrol also shows signs of inhibiting the replication of HSV in cell studies.[ref]Related article: Resveratrol: Genetic Interactions and Bioavailability
EGCG or green tea:
A component of green tea, EGCG also has been shown in cell-based studies to inhibit the replication of HSV.[ref]What about lysine?
Lysine is an amino acid that is often recommended for cold sores, but the study results are mixed. A meta-analysis of clinical trials on lysine for control of herpes simplex disease recurrence found that doses of 3 g/day or greater “appear to improve patients’ subjective experience of the disease.” Doses of 1 g/day were ineffective.[ref] Many of the clinical trials on lysine show that it doesn’t have much effect.Arginine restriction:
Arginine is an amino acid used by HSV for replication. The use of a low-arginine diet along with lysine seems to be a little more effective.[ref] Foods high in arginine include nuts, pumpkin seeds, chocolate, meat, fish, and tofu.Related article: Arginine genes
Kanuka honey: similar to acyclovir
A randomized trial compared kanuka honey to the most commonly prescribed antiviral, acyclovir. The results showed similar effectiveness for the honey vs. acyclovir (both took 8-9 days to completely clear the sore).[ref]Recap of your genes:
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