best l-lysine supplements

L-Lysine Supplement: Test & Reviews

Author: Anne Jonson

Diet & Nutrition Expert

Welcome to our big L-Lysine Test 2020. Here we present you all of the L-Lysine preparations that we have tested. We have compiled detailed background information for you and also added a summary of customer reviews on the web.

We want to make the purchase decision easier for you and help you to find the best L-lysine preparation for you.

You can also find answers to frequently asked questions in our guide. If available, we also offer you interesting test videos. You will also find some important information on this page that you should definitely pay attention to if you want to buy L-lysine products.

Best L-Lysin Supplements

Best L-Lysine capsules

A can of Greenfood L-Lysine contains 120 capsules, which consist of purely vegetable cellulose and contain no other additives. The product should be taken daily with plenty of water. One capsule contains 450mg and is therefore highly concentrated.

The gluten- and lactose-free Greenfood L-Lysine capsules were produced without genetic engineering in Holland through natural fermentation. They are also suitable for vegans and are very popular with buyers because the quality has proven itself and the capsules are very cheap. Magnesium stearate was dispensed with here, as was genetic engineering.

Best L-Lysine pills

The Vit4ever L-Lysine 2000 tablets are laboratory-tested and were manufactured according to European quality standards. Only premium raw materials were used. They are 100 percent vegan and free of colors, flavors and pollutants.

To make it easier to take Vit4ever L-Lysine 2000 tablets, they have a coating. They are also provided with a score line so that only half a tablet can be taken if necessary. The manufacturer recommends two tablets a day, which corresponds to a daily dose of 2000 mg. The can would then last for 180 days.

Best L-Lysine powder

The buXtrade L-Lysine powder is sold as a pack with 1 kg content. The manufacturer recommends taking 1,000 mg of it daily in juice or water between meals. The powder tastes slightly bitter, so mixing it with juice is definitely the better choice.

Thanks to the metallic-colored and resealable packaging, the buXtrade L-Lysine powder can be stored clean and dry and is protected from sunlight. Consumers appreciate the quality of this product at a low price.

Questions to Consider Before Buying L-Lysin supplements

What is L-Lysine?

In order for our body to function, it needs proteins, i.e. proteins. They are responsible for building muscle, transporting substances into the body cells and regulating chemical reactions. Proteins are made up of amino acids and L-lysine is one of them.
L-lysine is an essential amino acid, which means that we are not able to produce it on our own and therefore have to get it from food.

We need this amino acid in order to be able to survive in the long run, because it is important for building muscle and for the production of other amino acids.

It is also involved in bone growth, wound healing and cell division. In addition, L-lysine is required for the synthesis of antibodies and hormones.

L-lysine in particular is responsible for growth by helping the organism to absorb calcium.

L-lysine is also essential for the production of collagen and carnitine. L-lysine is an important component of collagen (connective tissue). Our organism contains approx. 600 g of L-lysine in the connective tissue.

Our body has to ingest 1.5 to 2 g of L-lysine daily through food. L-lysine is mainly found in animal protein (milk, meat, fish and eggs). It then enters the intestines, where it enters the blood through the intestinal wall and is then distributed throughout the body.

A lack of lysine can lead to decreased enzyme activity, a weakened immune system or even growth disorders.

Symptoms such as rough skin, brittle nails and hair loss are often the result of this deficiency, but also tiredness, red eyes, dizziness or nausea.

What symptoms can L-lysine help with?

L-lysine is essential. In the following cases, the additional intake of L-lysine through preparations can be helpful:

  • L-lysine used to treat obesity
  • L-lysine used to treat herpes
  • L-lysine used to treat cancer

L-lysine used to treat obesity

L-lysine contributes to normal metabolism, which can have a positive effect on weight loss.

L-lysine used to treat herpes

Herpes is caused by the type 1 herpes simplex virus. Usually this virus is not a big problem for the immune system and can be fought by it.

However, if your immune system is weakened, the virus can break out. L-lysine can prevent this or shorten the duration.

Herpes, or cold sores, as they are also called, usually appear on the lips. In rare cases, the vesicles can also be found in the nostrils, on the gums or on the roof of the mouth. The tiny blisters are often accompanied by itching, tickling or tingling.

The virus continues to lie dormant in the nerve cells even after healing. It can recur at any time due to a weak immune system, such as tiredness, stress, cold, flu, menstruation or sunburn.

Since the herpes virus is very contagious, direct physical contact or the sharing of cutlery, glasses, etc. should be prevented.

Now you are probably wondering what effect L-lysine can have on cold sores.

An amino acid called arginine helps this virus spread. On the one hand, we ingest them through food and, on the other hand, we produce a very small proportion of them ourselves in the body.

With L-lysine, arginine can be absorbed in the intestine. That means: With L-lysine the activity of arginine can be reduced. In the strict sense, these two amino acids are antagonists.

Studies have disagreed about the effects of L-lysine in treating herpes, but customer reviews clearly support it. There is currently a heated debate among researchers as to whether L-lysine affects the frequency of outbreaks or whether it has an influence on the duration of the disease.

An L-lysine dose of 1,000 mg daily is recommended for herpes.

L-lysine used to treat cancer

Due to the many side effects of conventional cancer treatments, the demand for natural alternatives is increasing. Researchers are finding more and more foods that are said to help fight the malignant cells.

Florida State University researchers studied the effects of L-lysine on cancer and the effects of L-lysine on damaged strands of DNA. They found that between 25 and 90 percent of cancer cells can be destroyed by lysine.

In 2014, the effect of lysine on colon cancer was also examined using mice. The study showed that the tumors shrank in the majority of cases.

L-lysine has great potential as a treatment for various types of cancer.

Where can I get L-Lysine?

Since lysine is an essential amino acid, it cannot be produced by the body. It must be ingested through food and supplements.
The main source of lysine is found in animal proteins. Meat, fish, eggs and dairy products are particularly rich in lysine. In a lower dose, lysine is also found in yeast, grains, legumes, soy, grapes, beets and orange-colored fruits such as apricots and oranges.

However, the amount is usually not enough to fully supply our organism with lysine and therefore vegans in particular often have to resort to dietary supplements. These should be taken on an empty stomach.

Does L-Lysine have any side effects?

Individual studies speak of a reduction in blood clotting by taking L-lysine.

For this reason, a therapeutic dosage (i.e. an increased intake of L-lysine) should be discussed with a doctor during pregnancy and before an operation.

In general, there are no known side effects and adults can take 3,000 mg L-lysine per day without risk.

Which dose is right for you?

Generally there is no danger when taking L-lysine. There cannot be an overdose because our body keeps the mirror in balance in two ways.
If your body has too much L-lysine, it is broken down by the liver into L-carnitine or excreted through the kidneys.

The recommended daily dose for adults is approximately 1,000 mg L-lysine. For specific treatment for a disease such as herpes, up to 3,000 mg of lysine daily is recommended, preferably in combination with vitamin C and zinc.

In children and adolescents, however, it is advisable to contact a doctor beforehand.

L-Lysine Alternatives

Normally, L-lysine is taken with food. Animal products have sufficient L-lysine for daily needs.

What types of L-Lysine supplements are there and which one is right for you?

If you want to consume L-Lysine, there are two options you can choose between:

  • L-Lysine from Animal
  • Vegan L-Lysine

You can find animal L-lysine almost everywhere, because it can also be ingested with food. Vegans have it a little more difficult and often have to resort to L-lysine supplements.

L-Lysine from Animal: Advantages & Disadvantages

Meat and fish are foods that are rich in L-lysine. Our organism should take in around 1.5 to 2 g of L-lysine daily through food. Then a defect should be excluded.

Only a few additional preparations are made from animal sources.


Vegan L-Lysine: Advantages & Disadvantages

It is particularly difficult for vegans to take enough lysine. Because vegan foods are relatively low in L-lysine. The use of alternative preparations is therefore advisable for vegans.

In recent years, the market for vegan food supplements has grown significantly. The L-lysine used in vegan products is made from glucose through fermentation, for example.

Purchase criteria: Use these factors to compare L-Lysine supplements

In the following we would like to show you the factors you can use to compare and evaluate L-lysine products. This will make it easier for you to decide whether a certain L-lysine preparation is right for you or not.

In summary, these are:

  • Dosage
  • Type of intake (powder or capsules)
  • Purity
  • Shelf Life


In general, you should consume around 1,000 mg of L-lysine daily. The dose in tablets and capsules usually varies between 500 and 1,000 mg.

If you do not consume animal protein, we recommend a preparation with 1,000 mg, although you can of course also take several capsules or tablets to achieve this value.

If the preparation is only taken as a supplement, 500 mg may be enough for you. If you are unsure, you should ask a doctor or pharmacist for advice.

Type of Intake

Most often you will find L-lysine in powder, capsule or tablet form. These preparations do not require a prescription.

There is also the possibility of taking L-lysine through infusions and special foods. In this case, however, you will need a doctor’s prescription.


The manufacturing process for tablets is somewhat more complex, which is why auxiliary materials often have to be used.

Therefore, L-Lysine tablets contain not only L-Lysine, but also fillers and separating agents. Most capsules, on the other hand, only consist of two ingredients, namely L-lysine hydrochloride and cellulose (plant fibers).

Shelf Life

Especially if you only use the additives to combat irregular diseases such as herpes, you should check the shelf life of the preparations so that you don’t have to throw away half a box later.

Facts about L-Lysine

Is L-Lysine Dangerous During Pregnancy?

Lysine cannot be produced by the body. Taking L-lysine is recommended during pregnancy and breastfeeding, as this amino acid promotes bone growth and cell division.

However, it is not recommended to exceed the daily dose. You should also ask your doctor about it.

Is L-lysine suitable for animals?

Like the human body, the animal organism cannot produce L-lysine itself. Therefore, dog and cat owners often ask themselves whether the animal should be given L-lysine.

Often lysine is destroyed in the feed production process and there is an L-lysine deficiency. A common symptom is the well-known cat flu or kennel cough.

For the animal’s eye function, it is often recommended to add a tablespoon of L-lysine powder to the feed.

Why is L-lysine often taken in conjunction with ibuprofen?

The pain reliever ibuprofen only works when it has dissolved in the intestine and enters the blood through the intestinal wall.

Lysine can accelerate the dissolution of ibuprofen in the intestine and the pain reliever can get into the blood faster. Pain relief occurs earlier.