Nitric Oxide And Erectile Dysfunction

By Johnathan P Cumberwell Reviewed By [Coming Soon]

Nitric oxide is a molecule that is produced inside the walls of your blood vessels.

And this nitric oxide is essential in order for you to get an erection.


Because after nitric oxide is produced, it is then diffused into the smooth muscles of your penis, where it makes these muscles relax.

When these smooth muscles relax (they are normally in a state of contraction), blood is allowed to flow into the penis and make it erect.

ED Lack Of Nitric Oxide

Therefore, you need adequate nitric oxide production to avoid erectile dysfunction.

Let’s fully explore this link between nitric oxide and erectile dysfunction.

The Link Between Nitric Oxide And Erectile Dysfunction

Nitric oxide is a simple molecule consisting of one atom of nitrogen and one atom of oxygen.

In the medical field, little attention was given to this molecule until the 1970’s.

But this changed in the 1970’s, when researchers discovered that nitric oxide had blood vessel dilation properties.

Meaning that it could expand blood vessels so that more blood could flow through the blood vessels.

Nitric Oxide Molecule

And it was also discovered that this nitric oxide is incredibly important in order for you to get erections, and therefore avoid erectile dysfunction.

Let me explain:

All blood vessels are lined by endothelial cells. These cells act as selective filters that regulate the passage of gases, fluids and various molecules across their membranes.

But not only that, these endothelial cells are also instrumental in the production of the signalling molecule and free radical nitric oxide.


Within these endothelial cells sit enzymes called nitric oxide synthase. And these enzymes are what produce nitric oxide.

Nitric Oxide Endothelium

What happens is that nitric oxide synthase takes a nitrogen atom from l-arginine, combines it with an oxygen atom from molecular oxygen, and voila! Nitric oxide is created.

And why is this nitric oxide so important?

Because this nitric oxide is an essential ingredient you need in order to get an erection.

When nitric oxide is formed in the endothelium in the blood vessels of your penis, it is then diffused into the vascular smooth muscle cells of your penis.

Here, it binds to and activates an enzyme called guanylyl cyclase. This enzyme converts a molecule called guanosine triphosphate to another molecule called cyclic guanosine monophosphate (cGMP).

And this does something very important:

Nitric Oxide Sex

It causes the smooth muscles in the penis to relax.

These smooth muscles are ordinarily in a state of contraction, which means that they clench together and do not allow blood to flow to the penis, other than for regular maintenance purposes.

But when cGMP instructs the smooth muscles to relax, a surge of blood freely flow into these smooth muscles, and the build-up of the erection starts.

To learn more about the erection process on Truelibido, please go here.

This smooth muscle relaxation is paramount for a penile erection to take place, as this allows blood to enter the penis.

No relaxation = no bloodflow to the penis = no erection.

No Nitric Oxide = No Erection

But This Is Not The Only Way Nitric Oxide Can Be Created

Because there is also a different way nitric oxide can be synthesized.

The process is as follows:

When you consume foods high in nitrates, such as leafy greens or beetroot, a certain bacteria that is normally present on the back of your tongue gets to work.

This bacteria likes the nitrate you consume because it can use it for energy.

Therefore, via chemical reactions, it starts to modify the nitrate.

So while this food is in your mouth and travels through your digestive tract, it is broken apart.

Beetroot Nitric Oxide

In the process of using nitrate to make energy, the bacteria utilize a nitrate reducing enzyme called nitrate reductase to generate nitrite from nitrate.

And once this nitrite is in your stomach, gastric acids act on the nitrite and convert it to three different molecules:

Nitrogen dioxide, dinitrogen trioxide and nitric oxide.

Therefore, your body can produce nitric oxide in a different way, and without the intervention of nitric oxide synthase.

That said, this mechanism is much less important for your ability to get erections than the production of nitric oxide via nitric oxide synthase.

Bacteria Nitric Oxide

Nitric Oxide And Viagra

In the late 1970s, researchers who were investigating the dilation mechanisms of the anti-angina drug nitroglycerine made a very interesting discovery.

By the way, angina is chest pain that occurs when your heart muscle doesn’t get enough oxygen-rich blood.

When this nitroglycerine was administered to angina patients, it reacted with other chemicals in the body and subsequently converted into nitric oxide.

And researchers discovered that it was in fact this nitric oxide that produced the potent vasodilation effects of the blood vessels, that benefited angina patients.

Then this finding initiated a whole new raft of research into nitric oxide.

And then came a chance discovery that changed the medical world forever:

Viagra Research


In the late 1980s, as nitroglycerine was given to angina patients, many of these patients experienced a rather peculiar side effect:


A large number of the angina patients got firm and long-lasting erections from the angina drug.

In fact, this experimental drug was far better at giving the patients erections than treating the angina condition.

What the researchers discovered, was that this nitric oxide acted as a messenger to the erectile tissue in the corpora cavernosa.

This lead to the development of the erectile dysfunction drug Viagra in 1989.

Viagra Nitric Oxide

However, it was not approved for use to treat erectile dysfunction by the FDA in the U.S. until 1998.

As a result, in 1998, three scientists received the Nobel Prize in Physiology for their discoveries of “nitric oxide as a signalling molecule in the cardiovascular system.”

Nitric oxide was also named the molecule of the year in 1992.

A Last Few Words About Nitric Oxide

Nitric oxide is what is called a free radical because it contains a single unpaired electron in its molecule.

Hence it is very reactive, and has a half-life of only a few seconds.

It is therefore normally not present in the body as nitric oxide, but reacts with other molecules to form more stable components such as nitrate.

Antioxidant Nitric Oxide

So when nitric oxide is created somewhere in the body, it has an almost immediate effect because of this very reactive property.

At the same time, unless there is an adequate and persistent supply of nitric oxide, the impact will wane quickly.

Nitric oxide has a multitude of functions in the body, and adequate levels of this messenger molecule are crucial for several bodily tasks to operate optimally.

Other than being paramount to proper erectile functioning, some of the most important roles of nitric oxide are:

  • It acts as a potent vasodilator that relaxes the arteries. Therefore, nitric oxide plays a critical role in regulating blood pressure and overall circulation, as well as helping the delivery of nutrients and oxygen to every system, organ, and tissue in the body.
Bloodflow Nitric Oxide
  • Nitric oxide plays an important role in bone formation and remodeling of old and damaged bones. Nitric oxide is utilized by cells called osteoblasts which are responsible for the maintenance and growth of bones.
Nitric Oxide Bone Formation

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Nitric Oxide Science

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Nitric Oxide Research

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Nitric Oxide Research Study

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Nitric Oxide ED Study

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Nitric Oxide Laboratory

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