L-arginine - A Scientifc Review (Benefits & Side Effects) (2024)

What is L-arginine?

L-arginine is a “conditional” amino acid found in protein foods like red meat, poultry, fish, dairy, whole grains, and beans[1].

What are Amino Acids?

There are 20 different amino acids and they are considered the building blocks of life. They are organic elements that join together to form proteins in the body.

Proteins complete various functions like repair tissue, build muscle, and aid in digestion.

There are technically 3 types:

• Essential
• Non-essential
• Conditional

Essential amino acids are just that – essential! We need to get them through our diet because our body does not make them. The 9 essential amino acids are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Non-essential amino acids, on the other hand, are produced by the body, but levels still need to get replenished through foods depending on the body’s state and fluctuating daily needs. The 11 non-essential amino acids are alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine.

Conditional amino acids are actually non-essential, but can become essential during times of stress and illness or if certain medical conditions or medications affect the body’s ability to naturally meet the body’s needs. The conditional amino acids are arginine, cysteine, glutamine, tyrosine, glycine, ornithine, proline, and serine.

Amino acids can be found in every type of food we eat – fruits, vegetables, whole grains, beans, lentils, dairy products, meat, and seafood. Eating a variety of foods every day helps you get all of the amino acids your body needs. Each amino acid is important and plays a specific role in your health, but there are a few amino acids of particular interest, like L-arginine.

Why Choose L-arginine?

L-arginine is attracting more attention because of its role in producing nitric oxide. Nitric oxide signals endothelial cell function that not only controls dilation and constriction of vessels in the heart and throughout the body, but enzymes involved in blood clotting and immune function as well.

Benefits

The top 5 and most scientifically supported benefits of taking L-arginine include:

1. Lowering blood pressure[7] in healthy individuals and those with high blood pressure, as detailed in our Juvenon Blood Flow-7 review article.

2. Treating and potentially preventing pre-eclampsia (high blood pressure and protein in urine) in pregnant women

3. Improving chest pain (angina)

4. Improving erectile dysfunction

5. Increasing blood flow in those with the peripheral arterial disease (PAD – a circulatory issue that reduces blood flow to limbs and causes pain)

Potential Side Effects

L-arginine is typically taken short-term and is generally well-tolerated, but side effects may include bloating, abdominal pain, diarrhea, gout flare-ups, and could induce an allergic response, swelling your airways or worsening asthma symptoms[8].

Considerations & Takeaway

It is challenging to distinguish which benefits of supplementing L-arginine are a result of correcting an already present L-arginine deficiency or are a result of taking additional L-arginine on top of an already sufficient level in the body. There is also some controversy about the safety of taking L-arginine long-term, like discussed in one study here. This particular study found L-arginine can be beneficial or harmful to your body’s cells depending on how long you supplement. The amount of L-arginine supplemented may also make a difference.

Although L-arginine may be beneficial for some individuals, like with any type of supplement, it is important to consult your doctor first prior to starting it to review the need for it and safety of it. Supplementing this amino acid may improve or worsen certain medical conditions and interact with current medications, herbs, or other supplements you are using.

Remember, L-arginine is just ONE of the 20 amino acids! Each amino acid plays a role in your health. Consuming a variety of foods that contain all of the amino acids should be your first step to improving your health before supplementing.

Frequently Asked Questions