Lysine Health Benefits

Lysine is an essential amino acid that the body uses for growth. It is essential because the body is unable to make it and it must be obtained from the foods you eat.

Studies suggest that taking this amino acid supplement along with dietary changes play an important role in reducing your chance of getting herpes outbreaks.

In additional to taking this supplement, foods high in lysine and low in arginine seems to help stop virus from recurring and from multiplying.

In addition to this amino acid, also consider other supplements to support your immune system when you are suffering from any type of viral infections. These supplements include zinc and vitamin C.

Scientific Evidence on the Benefits of L-Lysine

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Cold Sores (Herpes Labialis) / Herpes Simplex Virus (HSV 1)

Animal and clinical studies show that taking this amino acid helps to reduce the duration and severity of herpes infections.

See Cold Sores Home Remedies for things you can use at home to fight off annoying fever blisters.

As well, a cream that also contains zinc oxide was as useful in reducing the severity and duration of genital herpes infection.


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Anxiety and Stress

A Japanese study showed that a combination of L-lysine with L-arginine reduced stress levels in healthy subjects who are subjected to a high level of mental stress and anxiety.

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Genital Herpes / Herpes Simplex Virus 2 (HSV 2)

Lab and animal studies show that using lysine for HSV 2 prevents the virus from spreading.

This benefit has not be verified in human clinical trials so it is uncertain if this benefit can be expected in those suffering with genital herpes.

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Genital Warts / Human Papilloma Virus (HPV)

Lab studies and animal studies suggest that this essential amino acid could inhibit HPV multiplication.

A quick discussion can be found in the Lysine Usage in HPV Article.

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Genital Herpes / Herpes Simplex Virus 2 (HSV 2)

Lab and animal studies show that using lysine for HSV 2 prevents the virus from spreading.

No clinical studies are available to verify if this works in humans.

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Shingles (Varicella zoster)

This amino acid, in theory, may be helpful in reducing the time it takes to recover from an outbreak of shingles.

There are no research studies completed in human subjects to verify if this amino acid would be helpful for this condition.

The article Using Lysine for Shingle Infection discuss this benefit in detail.

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Ocular Herpes

Studies done on rabbits show that a lysine gel applied in the eyes healed lesions in 3 to 4 days.

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Hair Loss (Alopecia)

There is some suggestive evidence that a deficiency in this essential amino acid may contribute to hair loss, especially for women under the age of 50.

Keep in mind that some experts estimate that about 30% of women under the age of 50 suffer from minor forms of hair loss due to nutritional deficiencies.

What is not known is whether taking lysine would help with hair loss in a person who does not have a lysine deficiency.

See Hair Loss Remedies for a complete list of herbs and supplements that work.

See the typical dosage of L-lysine that is suggested by experts for treating viral infections.

Suggested Benefits and Traditional Uses

Here is a list of suggested uses for this essential amino acid.

  • Bell's palsy
  • high cholesterol
  • cold sores (herpes labialis)
  • genital herpes
  • herpes simplex virus (HSV)
  • osteoporosis / increase bone strength
  • rheumatoid arthritis
  • shingles
  • stroke risk reduction
  • viral infections
  • warts

Topical formulations containing lysine were used to treat the following health problems:

  • cold sores (herpes labialis) - (HSV 1)
  • genital herpes (HSV 2)
  • herpes simplex virus (HSV)
  • shingles
  • viral infections
  • warts

What is Lysine?

It is an amino acid that our body cannot manufacture (hence it is called an essential amino acid). The intestine absorbs L-lysine from the food source and it gets used to make proteins in our body.

If you get too much L-lysine in your diet or from your supplement, it is simply metabolized in the liver.

What are Some Foods High in Lysine?

Increase your body's lysine content by including in your diet foods rich in lysine.

Foods rich in lysine include brewer's yeast, dairy products, most fruits and vegetables, eggs, avocados, tomatoes and meat such as fish, chicken and beef.

There are also many others as well. You are sure to find one or two that you would enjoy eating on a daily basis.

See the article Lysine Rich Foods for a comprehensive list.

You can always take L-lysine supplements if you do not think you are getting enough in your diet.

What are Some Other Names for Lysine?

You might hear people refer to it as L-lysine or Lys.

Does Lysine Help Against Herpes?


In laboratory studies, L-lysine stops the herpes simplex virus (HSV) 1 and 2 from spreading. HSV 1 is responsible for causing cold sores and HSV 2 is responsible for causing genital herpes.

Both types of viral infection are highly contagious.

One large study involving 1,543 subjects showed that taking lysine supplements made their genital herpes sores, cold sores and canker sores much better.

Another study also showed that it reduced the duration of the herpes infection and also kept them away longer.

Overall, the larger study mentioned above showed good results as 80% of the subject reported significant benefits from using L-lysine. But this study, although large, has been criticized by experts for not being properly blinded to remove the placebo effect.

As well, there are some clinical studies that showed that taking lysine did not help any more than placebo (sugar pill).

What About Arginine? I've Heard that the Virus Requires Arginine?

This is shown to be the case.

The herpes simplex virus (HSV) requires another amino acid arginine for it to multiple and spread. It has a high requirement for arginine to reproduce, while L-lysine stops the viral replication.

One research study suggested that the ratio of L-lysine to arginine is more important. Therefore by taking more L-lysine relative to arginine, this may reduce herpes breakouts.

Foods that are rich in arginine that you might want to avoid include nuts, whole wheat, white flour products, lentils, brown rice, peanut butter, soybeans and tofu.

Side Effects, Toxicity and Warnings

What are some side effects, toxicity, dangers and interactions?

L-lysine is a safe amino acid to take. It has been shown in research studies done in both animals and humans.

Very few side effects were seen with even high doses of L-lysine.

Dosages above 40 grams daily have been reported to cause stomach pain, cramps and diarrhea.

The typical dosage used by most individuals should not cause any significant side effects, toxicity or danger.

There are some studies showing that L-lysine is safe to use in children and infants. Consult your physician if you plan on giving children L-lysine as a dietary supplement.

Dosage & How to Take It

The dosage commonly used in various research studies ranged from around 300 mg (0.3 gram) to 1,000 mg (1 gram) three times daily.

L-lysine comes in pills form (tablets and capsules), liquid, powder, cream, ointment and gel formulations.

Oral Dosage

For cold sores prevention, research studies used 1 gram daily for 12 months followed by a dose of 1 gram three times daily for another 6 months.

Some studies were carried out where the subjects were given lysine supplements for up to one year.

Topical Dosage

Apply L-lysine cream every 2 hours for up to 1 week. Super Lysine Plus+ was used in this study.

Bottom Line

There are some studies to show that the amino acid lysine could benefit those suffering from viral infections such as cold sores, shingles and HPV.

However, the results are only preliminary and there exist studies that showed that it was of no benefit even when taken for many months.

Despite these mixed results, it might still be a good idea for those who suffer from recurring cold sores to follow a diet that provides more lysine.

If they keep track of the number of outbreaks and their severity, they can track their own results and find out for themselves if a diet high in lysine actually helps them.

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