L-Arginine Benefits and Side Effects

L Arginine Benefits and Side Effects

L-arginine is most commonly known and used in the fitness industry for its ability to stimulate the release of growth hormone, hence its use in the body building world for enhancing stamina, strength and performance. In this post we will discuss in more detail L-Arginine benefits and side effects so you can work out whether this could be a supplement that is right for you.


What Exactly is L-Arginine?

L-arginine is an amino acid used by the body in the biosynthesis of proteins, and is found naturally in dairy products, red meat, fish, poultry and eggs. It is converted in the body to nitric oxide – a chemical that opens blood vessels wider, which in turn improves the flow of blood around the body.

It is a conditionally essential amino acid, meaning that it is not always essential, except maybe in times of illness and stress, such as the stress put on the body due to hard training or lifting weights. This will cause catabolic stress and injury, therefore the body requirements for L-arginine will be higher.

It has many other uses as well as just stimulating growth hormone, so let’s dive right in and take a look!





One of the most powerful effects of L-arginine is its ability to boost immune function and fight the inflammation that causes diseases in the first place. Out of control chronic inflammation is the root cause of almost every disease and illness of our tmes, therefore reducing it as much as possible is literally one of the BEST things we can do for our health.

Its antioxidant mechanisms help it to scavenge free radicals in the body, and these free radicals accelerate telomere aging And with the shortening of telomeres comes faster aging, and increased susceptibility to age related diseases such as cancer, diabetes, alzeimer’s, demetia and heart disease. Not a pretty story I know.



as we age our telomeres get shorter

Combining Supplements:

Supplementing L-arginine with a combination of vitamin C and Omega 3 fatty acids and you have an effective all round anti aging superstar. And if taken along with regular exercise (vital for heart health and to keep muscle mass up), especially as we age, then the hormonal changes that occur whilst supplementing L-arginine along with a regular training program will help build a more powerful, youthful and toned body.

L-arginine ALSO helps improve collagen synthesis in the skin – something that declines with age, and unfortunately for those who wish to stay youthful, makes skin thinner and less plump.

If you really want to slow the aging process further, then here is a helpful list of the 10 Ultimate Anti Aging supplements’Here you will find lots of useful information about slowing down the aging process, and helping the body to regenerate a more youthful glow and appearance NO MATTER WHAT YOUR AGE.


2. BOOSTS PERFORMANCE WHILST EXERCISINGl-arginine boosts exercise performance

As L-arginine improves the flow of blood so it is more easily able to transport nutrients and oxygen to muscle and joint tissues. This will have the effect of giving you less pain, both during and AFTER exercise of any kind (BUT, especially weight bearing exercise where muscles are more easily torn).

The main reason L-arginine is so commonly used in the body building and fitness industry is because of its ability to naturally increase the production of HGH ( human growth hormone), and other amino acids such as L-glutamate, L Proline and creatine.

L-arginine improves insulin sensitivity, making its part in metabolic health important for the building of lean muscle, fighting joint inflammation and pain; repairing injured tissue, and for soothing the central nervous system.


How Much Do I Need To Feel the Benefits?

The most powerful muscle building effects from L-arginine come when combined with exercise, especially weight bearing, gym, circuit training and boxing. Doses of 5-9 grams per day will increase resting growth levels by a minimum of 100%, and when exercising by up to 500%.



Male Fertility:l-arginine boosts male fertility

L-arginine helps blood circulation and the replication of cells, helping to improve sperm production and motility. Some studies show that combined with other anti inflammatory’s and antioxidants, L-arginine supplements can significantly improve up to 92% of male infertility cases.

This proves even more true for highly stressed men, as stress lowers L-arginine in the sperm production paths, and supplementation has also been proven to work more effectively when combined with L-glutamate and Yohimbine Hydrochloride.


Female Fertility:

L-arginine can also be beneficial in the treatment of female infertility as it actually increases the circulation to the genital tissue in both sexes. Research suggests that L-arginine and NAC together may help to naturally balance hormones, playing a role in helping to alleviate imbalances of estrogen, and PCOS.



Not only does L-arginine supplementation support cardiovascular and kidney health, but it also regulates the immune system by positively affecting immune responses and inflammation. I found during research, many studies to support these findings, especially when supplemented along with omega 3 fatty acids and other antioxidants, such as Vitamin E and Vitamin C.



L srginine lowers blood pressure


As a popular supplement recommended by cardiologists, L-arginine improves heart health by lowering inflammation, boosting the health of blood vessels and the health of the whole cardiovascular system, lowers high blood pressure and improves stamina.

And for those at high risk of heart disease, then supplementation of L-arginine may act as a powerful and preventative measure against stroke and heart attack.



L-arginine is already made in adequate amounts by the body in somebody who eats a healthy diet, and therefore no supplementation is required. However, in those partaking in high amounts of physical activity, and looking to cut fat and build muscle, then this could be a helpful supplement in that process and may give you the extra edge you need.

I must reiterate again, that I can only find evidence of L-arginine’s usefulness when used either for medical reasons OR in combination with physical exercise, as the body has a higher demand for amino acids due to rebuilding torn muscle tissue. In most other cases you should simply get enough from your diet alone.



2-3 grams up to 3 times daily is the adequate amount that has been studied in trials, but ALWAYS buy from reputable companies and always read labels carefully. Do not exceed recommended doses.

Good quality supplements – Amazon L Arginine Capsules


L-arginine is safe for most people when taken in capsules, powder, administered in a shot, or applied to the skin in appropriate doses.

In clinical settings, L-arginine has been trialed safely with only minor side effects, and has been proven to be beneficial in those who need it for medical reasons (in which case consult with your doctor first), or those who are doing a lot of physical activity and are looking to get into shape, cut fat and build muscle.

Possible side effects may include: Bloating, diarrhea, gout, allergies, inflammation of airways, asthma may worsen, may interact with medications that lower blood pressure.


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Stefanie Taylor
I have studied nutrition for many years, and have since discovered that a plant based diet has been the most beneficial to my health and body. I have more energy and zest for life than I have ever had and this website is dedicated to helping others who wish to know more, and start out on this lifestyle.

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10 Comments on "L-Arginine Benefits and Side Effects"

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William Murphree

nice article I have been using l arginine for some time. My wife found out about it.


That’s interesting William, I would be interested to know how you feel it is working for you and if you have any side effects? Thank you for reading.


Wow this stuff is great, I just bought some of this stuff, but the dosage is on milligrams, I take 8.5 milligrams is that too much???

Hi Jalal ok don’t panic, usually the dosage is in grams as it is quite a bulky thing (you can even find it in powder form). In my article I speak of the dosage in grams (there are 1000 milligrams in 1 gram), so you are actually taking a minute amount so definitely not too much. I can only presume you have got in some kind of really condensed extracted form which could explain why it is in such tiny amounts. I would just take what it says on the label as it has obviously been worked out correctly. But… Read more »

I actually do intermittent fasting and I really would love to have the benefits of l arginine but my coach says I should not take it before workouts. What do you recommend for people who do intermittent fasting?

Hi Furkan, thanks for reading. I don’t know the specific reasons why your coach has told you not to take it before your workouts as in the research I have done I have found a lot saying you should take it both before (30-60 mins)and also after. Some people have side effects of stomach ache and nausea etc so I presume if you are one of those people then you shouldn’t take it before. Anyway, maybe you could ask your coach and let me know his reasons as I would be intersted, and I want to make sure that I… Read more »

Very interesting article about L Arginine. All of the information that is needed on this subject is shown here. You had given other uses for this supplement besides body building.


Hi Tony, thanks for reading and yes there are many reasons to use this supplement, including medically, which is an eye opener for most people. Very interesting indeed!


Very interesting and helpful. I’m interested in anything thats anti aging these days. Also keeping up with my health from the inside out. Thank you for this article


Hi Toni, glad you found this interesting, a lot of people are getting into the healthy thing these days, which is great. Just keep everything natural and you won’t go far wrong.