Nitric Oxide Supplements: Uses & How They Work

If you’ve been investigating how to improve your blood flow to address erectile dysfunction, it’s probably been hard to read much information without seeing a mention of nitric oxide.

Available without a prescription, many nitric oxide for ED supplements claim to boost blood flow, giving you stronger erections and better physical performance and athletic performance.

Nitric oxide isn’t just another supplement ingredient — it’s real science. And while these products certainly can deliver on many promises, seeing that they do so safely presents a health risk for you to manage.

How do you weigh that against the benefits? It’s complicated. Below, we’ve explained:

  • What nitric oxide is and how it’s necessary for your body

  • The science behind nitric oxide for ED

  • Whether or not they’re worth using for better physical health and erections

We’ve also shared a few other, evidence-based treatment options that you may want to consider if you suffer from erectile dysfunction (ED).

What Does Nitric Oxide Do?

Nitric oxide is a molecule naturally produced inside your body that works as a type of signaling molecule for your cells and organs. In fact, it plays a role in almost every cellular and organ function in your body as it’s converted to nitrate.

Its key role, however, is to regulate the blood flow of your vascular system — the complex network of blood vessels that transports oxygen and nutrient-rich blood to your organs and is charged with removing waste products.

Nitric oxide is also known as a vasodilator. It’s a chemical that increases blood flow and promotes lower blood pressure through its effects on soluble guanylate cyclase (sGC), a type of enzyme found in the smooth muscles of your blood vessels.

When soluble guanylate cyclase is activated, your blood vessels can relax, allowing for better blood flow to certain parts of your body.

That’s a lot of jargon to explain that nitric oxide helps blood move more easily to where it’s needed. And that’s really important for erections.

Does Nitric Oxide Help Sexually?

Nitric oxide relaxes the vascular muscles in the arteries that supply your penis with blood when you’re sexually aroused.

This increase in blood vessel diameter and blood flow is what allows your penis to get firm and erect while you’re having sex. So yeah, that’s really, really important.

Because nitric oxide plays such a major role in healthy erections, medical conditions that reduce your production of nitric oxide can potentially contribute to erectile dysfunction. 

And the risks don’t stop at erectile efficiency. Low nitric oxide levels may also contribute to a higher risk of common heart health issues, such as cardiovascular disease.

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What Are Nitric Oxide Supplements?

Nitric oxide supplements are exactly that — supplements that claim to increase levels of nitric oxide within your body.

They’re available without a prescription as pre-workout style powdered drinks, beetroot extracts or capsules, and can be purchased from drug stores, health food stores and, yes, even online.

There’s a bit of a catch to these supplements, though, and it has to do with what’s actually inside them.

Most of the time, dietary supplements have the same active ingredient as their name suggests. For example, creatine supplements contain creatine, and protein supplements contain different types of protein.

Nitric oxide supplements, on the other hand, contain active ingredients that are used within your body to increase its own nitric oxide production.

More specifically, most nitric oxide boosters contain the active ingredients L-arginine and L-citrulline. These amino acids act as biological “building blocks” for nitric oxide within your body.

The idea behind these supplements is that giving your body the nutrients it needs to produce its own nitric oxide will increase nitric oxide levels.

Nitric Oxide Benefits, According to Research

As with lots of dietary supplements, many of the studies used to support the idea that nitric oxide precursors boost nitric oxide production are actually animal research, and not studies involving humans. So, while we know that nitric oxide is essential and the benefits of delivering it definitely exist, the data on whether supplements work is a little more sparse.

For example, one study published in 2014 in the journal Biochemical and Biophysical Research Communications found that oral use of the amino acids L-arginine and L-citrulline — the two amino acids typically used in nitric oxide supplements — increased nitric oxide levels in rats and rabbits.

But that’s not to say there aren’t some promising studies involving people on whether supplements can boost nitric oxide or not.

Prelox®, a combination of L-arginine aspartate and Pycnogenol® (another popular natural supplement otherwise known as maritime pine), was shown to support nitric oxide production in clinical trials.

Notably, a study looking at L-arginine and L-citrulline levels in men found that men with severe ED had lower levels of these two amino acids, thereby reducing nitric oxide.

Improved sexual function was also reported in nine patients with decreased NO production or excretion who took L-arginine supplements to boost their nitric oxide levels.

And finally, a three-month trial using Pycnogenol to increase L-arginine and NO levels saw just over 92 percent of men experiencing normal erections.

You might be thinking, “Hey, all this research on humans looks good! 92 percent is a great number for erections!” And you’re not wrong.

But many of these studies were on the smaller side. So while they’re promising, it doesn’t necessarily mean that supplements for nitric oxide work for everyone.

A review published in the journal Sports Medicine found that nitric oxide supplements do appear to offer exercise-related benefits, including increased exercise performance.

It’s worth noting that these effects were observed in people with low to moderate prior training — in more highly trained people, nitric oxide supplements didn’t show any effects.

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Do Nitric Oxide Supplements Help With ED?

The role of nitric oxide is well understood, but its pharmacological use for improved erectile response is not currently approved for the treatment of erectile dysfunction.

As such, there aren’t any “best nitric oxide supplements for erectile dysfunction” on the market that have been approved by the FDA to treat erectile dysfunction, which means your provider probably won't be raving about how excited they are to recommend them to you.

But these supplements may have some effect on ED. Although nitric oxide supplements shouldn’t be viewed as a treatment for ED, a small amount of research suggests that there may be benefits of nitric oxide for erections and male sexual function. In addition to what’s been mentioned above:

  • L-citrulline is an amino acid that increases the production of nitric oxide, which is needed to relax the smooth muscles in the arteries that supply blood to the penis so its chambers can fill with blood, causing an erection. One study found that L-citrulline supplementation improves erection hardness in men with mild erectile dysfunction.

The research we have looks promising, but we need a lot more before anyone can say anything definitive about the efficacy of these supplements.

Nitric Oxide Side Effects

One of the biggest problems with supplements is that, because the FDA doesn’t have the same oversight of them, they can be less predictable (and less safe) than medications.

Nitric oxide supplements could boost nitric oxide in your body, but they may cause unwanted effects when you take them. For nitric oxide, those side effects may include:

  • Upset stomach

  • Racing heartbeat

If you experience dizziness, chest pain or other issues when taking nitric oxide supplements, seek immediate medical attention.

Alternatives to Nitric Oxide for ED 

The best nitric oxide supplements for ED may work, but they’re not what experts recommend. Luckily, if you're looking for more proven ED treatments, options abound to improve blood flow.

Medications approved by the FDA and changes to your lifestyle can do more than supplements in almost all cases. Let’s look at how.

FDA-Approved ED Medications

Currently, the FDA has approved four science-backed oral medications for erectile dysfunction:

These medications belong to a class of drugs called PDE5 inhibitors, which work by preventing the enzyme phosphodiesterase type 5 from restricting blood flow to the erectile tissues located inside your penis.

They can be taken as-needed before sex, making it easy to deal with erectile dysfunction (ED) and improve your sexual performance.

In addition to these oral medications, other medications are also available for ED, such as alprostadil — an injectable.

Lifestyle and Habits

You can also reduce your risk of dealing with erectile dysfunction by making healthy changes to your habits and lifestyle.

Several things may help improve your sexual function and prevent ED. For example:

  • Exercising regularly

  • Maintaining a healthy weight

  • Limiting your alcohol intake

  • Quitting smoking

  • Avoiding illicit drugs

Our guide to naturally protecting your erection goes into more detail about these techniques and other approaches that you can use to improve your sexual function naturally.

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Nitric Oxide for ED: Should You Use Them?

Nitric oxide is an important signaling molecule that your body uses for a wide variety of different functions, including supplying blood to your penis when you’re aroused. It’s certainly an essential biological ingredient. But supplementing it isn’t a plan without risks.

Consider the following when weighing your choices:

  • Research on nitric oxide supplements and ED is limited, but some studies suggest that the L-arginine and L-citrulline found in nitric oxide supplements may help to improve ED in some men.

  • However, you’ll notice the biggest improvements from evidence-based medications like sildenafil (Viagra), tadalafil (Cialis) and avanafil (Stendra).

  • Lifestyle changes can also improve your cardiovascular health and well-being.

If you’d prefer to go the smart and safe route, we offer several erectile dysfunction medications online, following a consultation with a licensed healthcare provider who will determine if a prescription is appropriate.

Interested in learning more about dealing with ED? Our detailed guide to the treatment options for erectile dysfunction shares more about how you can improve your erections and have better sex, from medication to psychotherapy, pelvic floor exercises and other approaches.

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment or medication.

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