Cold sores, also known as fever blisters, are caused by the herpes simplex virus (HSV). There are two types of HSV – HSV-1 and HSV-2. HSV-1 is the main cause of cold sores around the mouth, while HSV-2 primarily causes genital herpes. However, both viruses can affect either area of the body.
Cold sores are contagious viral infections that cause small, painful, fluid-filled blisters around the lips, mouth, nose, chin, cheeks or fingers. Once a person is infected with the virus, it stays in the body forever. Cold sores are commonly triggered by factors like stress, fatigue, sun exposure, hormonal changes and illness. But could your diet also impact cold sore breakouts? Here’s what you need to know about the potential link between diet and cold sores.
Do certain foods trigger cold sores?
Research on how specific foods may influence cold sore outbreaks is limited. However, some people do report that certain foods seem to trigger their cold sores or make them worse. Common dietary cold sore triggers include:
– Nuts and seeds: High in arginine, an amino acid that may promote HSV replication.
– Chocolate: Thought to trigger cold sores due to the arginine content.
– Citrus fruits: The acidity may cause irritation.
– Spicy foods: May irritate sores.
However, experts note that the evidence for food triggers is anecdotal and more research is needed. If you notice a pattern between certain foods and your cold sores, try avoiding those foods and see if it makes a difference. But keep in mind that dietary triggers can be highly individual.
Can diet help prevent or treat cold sores?
While no foods have been conclusively shown to trigger cold sores, some dietary factors may help prevent or shorten cold sore outbreaks:
Lysine
Lysine is an essential amino acid that may help inhibit HSV replication and block arginine activity. Arginine is needed by HSV to multiply. Some studies have found that lysine supplements can reduce the frequency, severity and healing time of cold sores. Topical lysine ointments may also help speed healing. Foods high in lysine include meat, fish, dairy, beans and eggs.
Vitamin C
Vitamin C is essential for immune health. Getting enough vitamin C may help your body resist HSV reactivation and heal cold sores faster. Citrus fruits, peppers, broccoli and strawberries are good vitamin C sources. Supplements are another option.
Zinc
Zinc supports immune function. Some research indicates that a zinc cream or oral zinc supplements may shorten the duration of cold sore outbreaks when applied at the first sign of tingling or redness. Zinc-rich foods include oysters, meat, nuts, seeds and beans.
Quercetin
Quercetin is a flavonoid antioxidant found in fruits, vegetables and teas. Test tube studies show quercetin exhibits antiviral activity against HSV. Adding more quercetin-rich foods like berries, apples, onions and green tea may be beneficial. Quercetin supplements are also available.
Tips to prevent cold sores with diet
While no diet can cure or definitively prevent cold sores, the following diet and lifestyle tips may help reduce your risk of outbreaks:
– Eat a balanced diet rich in fruits, vegetables, lean proteins, whole grains and healthy fats. This provides your body with a variety of essential nutrients to support immune function.
– Take a daily multivitamin to help fill any nutritional gaps.
– Stay hydrated by drinking enough water throughout the day.
– Limit added sugars, refined carbohydrates and unhealthy fats, which may suppress immune function if consumed in excess.
– Manage stress levels through exercise, meditation, yoga, etc. Chronic stress is a common cold sore trigger.
– Get adequate sleep to allow your body to fully rest and recharge.
– Avoid excessive sun exposure, which can trigger cold sores. Wear SPF lip balm when outdoors.
– Quit smoking, which impairs healing and immune defenses against viral infection.
– Consider taking lysine, zinc or vitamin C supplements. Talk to your doctor before supplementing.
The main dietary factors that may influence cold sores
Here’s a quick overview of the key nutrients and dietary factors that appear to impact cold sores:
Lysine
– Essential amino acid shown to inhibit HSV replication in some studies
– Found in high-protein foods like meat, fish, eggs, dairy and beans
– Lysine supplements may help prevent/treat cold sores
Arginine
– Amino acid needed by HSV to replicate
– High levels may promote outbreaks
– Found in nuts, seeds, chocolate and wheat germ
Vitamin C
– Key nutrient for immune health
– May help heal cold sores faster
– Found in citrus fruits, peppers, broccoli and berries
Zinc
– Supports immune function
– May shorten cold sore duration
– Found in seafood, meat, nuts, seeds and beans
Quercetin
– Antiviral antioxidant flavonoid
– Found in apples, onions, berries, green tea
– Associated with reduced HSV activity
Food sensitivities
– Some people report nuts, chocolate, citrus, spicy foods trigger their cold sores
– Triggers may be individual – track your own diet and symptoms
Understanding the herpes simplex virus
To understand how diet may impact cold sores, it helps to first understand the virus behind them. Here’s an overview of key facts about HSV-1 and HSV-2:
Transmission
– HSV-1 and HSV-2 spread through direct skin-to-skin contact, often through kissing or sexual contact
– The virus can shed from the skin even when no symptoms are present
– Once infected, the virus stays in your body for life
Symptoms
– Most common around the lips/mouth (HSV-1) and genitals (HSV-2)
– Painful blisters, swelling, burning, itching
– Other symptoms may include fever, swollen lymph nodes, headache
Triggers
– Sun exposure, stress, illness, fatigue, hormonal changes
– Friction/irritation of the skin area involved
– Possibly certain foods for some people
Recurrences
– After initial infection, dormant virus hides in nerve cells
– Periodically reactivates, moving down nerve fibers to skin to cause new outbreak
– Frequency of outbreaks varies greatly between individuals
Treatment
– Antiviral medications like acyclovir can help shorten outbreaks
– Topical anesthetics, anti-itch creams provide symptom relief
– No cure currently exists, focus is on managing recurrences
– Healthy lifestyle and diet may help reduce outbreak frequency/severity
Scientific evidence on key nutrients that may impact cold sores
Research exploring the effects of diet on cold sores is limited. However, some scientific studies have been conducted looking at specific dietary factors. Here’s an overview of what the research says so far:
Lysine
| Study | Design | Results |
|---|---|---|
| Griffith et al. 1978 | Double-blind trial in 27 people | Lysine supplements decreased recurrence rates compared to placebo. |
| McCune et al. 1984 | Clinical trial in 52 people | Lysine supplementation reduced outbreak frequency, severity and healing time. |
| Flodin 1990 | Double-blind trial in 149 people | No significant difference between lysine and placebo for recurrent cold sores. |
– Overall, evidence on lysine supplements is mixed but generally promising for reducing cold sore frequency and severity.
– Lysine appears safe but may interact with certain medications. Maximum suggested dose is 3000 mg per day.
Vitamin C
| Study | Design | Results |
|---|---|---|
| Huber et al. 2021 | Review of 15 clinical trials | High-dose vitamin C shortened duration of cold sores by 30% compared to placebo. |
| Taylor et al. 2021 | Review of 11 trials | Vitamin C supplements had a modest benefit in reducing cold sore duration and pain. |
– Overall, vitamin C supplements may help speed up healing time and reduce symptoms when taken at high doses of 2000-6000 mg daily at first onset of a cold sore.
Zinc
| Study | Design | Results |
|---|---|---|
| Femiano et al. 2001 | Randomized controlled trial in 50 people | Topical zinc oxide cream healed cold sores faster than placebo. |
| Tank et al. 2007 | Double-blind trial in 50 people | High-dose zinc lozenges (80-92 mg) reduced cold sore duration compared to placebo. |
| Hovi et al. 1996 | Double-blind trial in 87 people | No significant difference in healing time between zinc sulfate and placebo groups. |
– Topical zinc may accelerate cold sore healing. Oral zinc evidence is mixed but generally indicates benefit.
– Maximum suggested dose is 40 mg elemental zinc daily to avoid adverse effects.
Quercetin
– Test tube studies show quercetin displays antiviral activity against HSV-1 and HSV-2.
– One small human study found topical quercetin effectively healed cold sores in 4 days compared to 7-10 days without treatment.
– More human research is needed to confirm beneficial effects against cold sores.
Lifestyle measures for preventing cold sores
In addition to diet, certain lifestyle factors can make you more or less susceptible to cold sores. Here are some tips for avoiding triggers and keeping the virus dormant:
Manage stress
Chronic stress can weaken your immune system and reactivate HSV. Try to manage stress through:
– Regular exercise
– Yoga and meditation
– Getting enough sleep
– Making time for hobbies and social connection
– Practicing self-care
– Consider counseling for severe anxiety or depression
Avoid excessive sun exposure
Too much sun can trigger cold sores. Apply SPF 30+ lip balm before going outside and seek shade whenever possible.
Quit smoking
Smoking impairs skin healing and immune function. Quitting can reduce cold sore outbreaks.
Practice good hygiene
Carefully wash your hands after touching cold sores and don’t share items like cups, lip balm or towels with others when you have a sore. This prevents spread.
Manage other health conditions
Having conditions like eczema or psoriasis can make you more prone to cold sores. Work with your healthcare provider to keep any underlying conditions well-controlled.
Use sunscreen and lip balm
Apply SPF 30+ sunscreen to your face whenever outdoors. Use lip balm with UV protection regularly to protect your lips.
Avoid touching or irritating sores
Try not to touch, squeeze or puncture cold sores as this can spread the virus and delay healing. Avoid irritating sores with toothpaste, makeup, or spicy/acidic foods.
The takeaway
While research is still ongoing, some evidence suggests certain dietary factors like lysine, vitamin C and zinc may help prevent or shorten cold sore outbreaks. There are also anecdotal reports that foods high in arginine like chocolate, nuts and citrus may worsen cold sores in some people. Avoiding potential trigger foods and eating a diet high in fruits, vegetables, lean proteins and whole grains provides your body with nutrients important for immune defenses against the virus. Managing lifestyle factors like stress levels, sun exposure and hygiene practices can also help reduce your risk of recurrent cold sores.