Evidence Based
4.1 /5
12

8 Lysine Benefits + Foods High In Lysine

Written by Mathew Eng, PharmD | Last updated:
Evguenia Alechine
Jonathan Ritter
Puya Yazdi
Medically reviewed by
Evguenia Alechine, PhD (Biochemistry), Jonathan Ritter, PharmD, PhD (Pharmacology), Puya Yazdi, MD | Written by Mathew Eng, PharmD | Last updated:

SelfHacked has the strictest sourcing guidelines in the health industry and we almost exclusively link to medically peer-reviewed studies, usually on PubMed. We believe that the most accurate information is found directly in the scientific source.

We are dedicated to providing the most scientifically valid, unbiased, and comprehensive information on any given topic.

Our team comprises of trained MDs, PhDs, pharmacists, qualified scientists, and certified health and wellness specialists.

All of our content is written by scientists and people with a strong science background.

Our science team is put through the strictest vetting process in the health industry and we often reject applicants who have written articles for many of the largest health websites that are deemed trustworthy. Our science team must pass long technical science tests, difficult logical reasoning and reading comprehension tests. They are continually monitored by our internal peer-review process and if we see anyone making material science errors, we don't let them write for us again.

Our goal is to not have a single piece of inaccurate information on this website. If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please leave a comment or contact us at [email protected]

Note that each number in parentheses [1, 2, 3, etc.] is a clickable link to peer-reviewed scientific studies. A plus sign next to the number “[1+, 2+, etc...]” means that the information is found within the full scientific study rather than the abstract.

Cold sore

Lysine is an essential amino acid that plays a vital role in the body and is a necessary part of the diet. Find out what lysine is, what are its benefits and side effects, and which foods are great sources of this amino acid.

What Is Lysine?

Lysine is an essential amino acid that plays an important role in the creation of proteins in the body. The human body is unable to produce lysine itself. This means that lysine must come from external sources — primarily food.

Some biological functions of lysine include [1, 2, 3]:

  • Serving as a building block for proteins
  • Playing an important role in histone modification (which affects gene expression)
  • Providing structure to collagen
  • Regulation of calcium levels

Lysine, as an oral supplement or lip balm, is often used for treating and preventing cold sores. Some other popular purported health benefits include improving athletic performance, canker sore symptoms, and schizophrenia symptoms. 

However, there is a lack of clinical studies to support most of these claims. We’ll dive into the research concerning lysine in the following sections.

Snapshot

Proponents

  • May help prevent or treat cold sores
  • May help prevent or treat canker sores
  • May reduce anxiety
  • May reduce schizophrenia symptoms
  • May help improve diabetes

Skeptics

  • Lack of strong clinical research to support health claims
  • Diet usually provides more than enough lysine
  • Supplements may cause diarrhea and stomach pain

Purported Health Benefits Of Lysine

Possibly Effective For:

1) Treatment and Prevention of Herpes (Cold Sores)

Herpes labialis, more commonly known as cold sores, are caused by an infection by the herpes simplex virus. There is some evidence that lysine, either taken orally or applied topically, is possibly effective for reducing the duration and severity of cold sores.

A number of older clinical trials suggest that oral lysine supplements may reduce the recurrence of cold sores as well as the severity and duration of symptoms [4, 5, 6, 7, 8].

According to a more recent pilot study of 30 people, a specific herbal-based product containing lysine and zinc may also reduce the duration of cold sore episodes [9].

However, not all the evidence supports this use of lysine. A systematic review of 32 clinical trials including 2640 patients examined the effectiveness of many different treatment options for cold sores. According to researchers, there is not enough clinical research to be able to recommend oral or topical lysine for cold sores [10].

Insufficient Evidence For:

The following purported benefits of lysine are only supported by limited, low-quality clinical studies. There is insufficient evidence to support the use of lysine for any of the uses listed below. Remember to speak with a doctor before taking lysine. It should never be used as a replacement for approved medical therapies.

2) Canker Sores

While they appear similar to cold sores, canker sores do not occur on the surface of the lips and are not contagious. There is also much less research on the effectiveness of lysine for canker sores.

Only one older study suggests that 500 mg of lysine daily may help prevent canker sores [11].

3) Anxiety

A 3-month randomized study performed in communities in Syria found that wheat fortified with lysine may reduce anxiety and stress [12].

According to a randomized placebo-controlled study of 108 healthy Japanese adults, oral supplementation with both lysine and arginine (another essential amino acid) may reduce anxiety and cortisol levels [13].

4) Schizophrenia

A small randomized placebo-controlled study of 10 patients with schizophrenia found that high dose supplementation of lysine at 6 g per day (in combination with conventional antipsychotic medication) may decrease the severity of positive symptoms [14].

Another randomized placebo-controlled trial of 72 schizophrenia patients also examined the effects of high dose (6 g per day) lysine supplements as an add on to conventional treatment. In contrast to the previously mentioned study, researchers found potential improvements to negative and general symptoms, but not for positive symptoms [15].

5) Diabetes

A small study of 8 patients with type 2 diabetes found that oral lysine supplements may lower blood glucose levels [16].

Another pilot study of 77 diabetic patients also found that oral supplementation with lysine may decrease blood glucose levels and improve insulin sensitivity [17].

In addition, a small study of 13 healthy subjects shows that lysine may decrease blood glucose levels while increasing glucagon and insulin levels [18].

6) Muscle Strength

According to a study of 40 healthy men, 8 weeks of a high lysine diet (defined as 80 mg/kg each day) may improve muscle strength compared to a low lysine diet [19].

7) Bone Health

Two studies of 30 and 45 patients with osteoporosis found that dietary supplementation with lysine may improve the absorption of calcium. According to researchers, this may be helpful for those with osteoporosis [3].

8) Pressure Ulcers

Pressure ulcers, also known as bedsores, are caused by prolonged pressure on the skin, usually from staying in one position for too long. This type of ulcer is especially a concern in patients that are hospitalized for long periods of time [20].

A study of 50 hospitalized patients found that a specific cream containing lysine and hyaluronic acid may help reduce the size of ulcers and healing time [20].

Safety of Lysine

Lysine is generally considered possibly safe. Studies have used oral lysine supplements for up to a year without any safety concerns. Topical forms of lysine have only been studied in short-term trials — their long-term safety is unclear [4].

There is also insufficient evidence to determine if lysine supplements are safe to use during pregnancy or breastfeeding.

Side Effects

The most commonly reported side effects of lysine supplementation include stomach pain and diarrhea.

Precautions

Calcium Absorption

There is some evidence that lysine may increase calcium absorption. Those with too much calcium in the blood (hypercalcemia) may need to avoid lysine supplements [3].

Kidney Disease

There is one case report of a person developing chronic renal failure after taking high amounts of lysine over a five-year period [21]

Intolerance to Lysinuric Protein

Lysinuric protein intolerance is a genetic condition that impairs the absorption of amino acids like lysine. Supplementation with lysine in people with this condition may cause diarrhea and stomach cramps [22, 23].

Supplementation

In the following sections, we’ll discuss the common forms and dosages of lysine supplements that are commercially available. Lysine supplements are not approved by the FDA for medical use. Regulations set manufacturing standards for supplements, but that does not guarantee that they are safe or effective. Speak with your doctor before supplementing.

Forms

Lysine is commercially available as capsules, tablets, ointments, lip balms, and as a powder.

Most products refer to lysine as L-lysine, which is the biologically active form of the amino acid.

Dosage

There is currently insufficient evidence to determine what a safe and effective dose of lysine is for specific conditions.

For cold sores, clinical trials have used doses that range from 500 to 3,000 mg total each day [7].

The strength of commercially available oral lysine supplements typically ranges from 500 to 1,000 mg per dose. Manufacturers usually recommend taking 1 to 3 doses each day.

Natural Sources of Lysine

The body is unable to produce lysine, so it is important to get enough lysine in the diet. Luckily, in countries like the U.S., most people get more than enough lysine from meat and vegetable sources [24].

The recommended intake of lysine for adults is 30 mg/kg. According to some studies, most people in the Western world get about 40-180 mg/kg of lysine [24].

Some great sources of lysine include:

  • Lean beef and lamb – 3582 mg/100g
  • Parmesan cheese – 3306 mg/100g
  • Poultry (turkey, chicken) – 3110 mg/100g
  • Pork – 2757 mg/100g
  • Soya beans and products (tofu, protein powder, flour) – 2634 mg/100g
  • Tuna – 2590 mg/100g
  • Shrimp – 2172 mg/100g
  • Pumpkin seeds – 1386 mg/100g
  • Eggs – 912 mg/100g
  • White beans – 668 mg/100g [25]
  • Other fish (cod, sardine) and shellfish
  • Nuts, seeds, eggs, beans, and lentils
  • Spirulina and fenugreek seeds [26]

Buy Lysine Supplements

About the Author

Mathew Eng

Mathew Eng

PharmD
Mathew received his PharmD from the University of Hawaii and an undergraduate degree in Biology from the University of Washington.
Mathew is a licensed pharmacist with clinical experience in oncology, infectious disease, and diabetes management. He has a passion for personalized patient care and believes that education is essential to living a healthy life. His goal is to motivate individuals to find ways to manage their chronic conditions.

Click here to subscribe

RATE THIS ARTICLE

1 Star2 Stars3 Stars4 Stars5 Stars
(80 votes, average: 4.05 out of 5)
Loading...

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.