What's the Best Nitric Oxide Supplement?

Nitric oxide supplementation, not to be confused with inhaling actual nitric oxide gas, entails the use of nutrients and other bioactive substances that increase nitric oxide production in the body. Since nitric oxide is an essential vasoregulating chemical, taking nitric oxide supplements can modulate blood pressure, support cardiovascular function (e.g. blood flow), enhance athletic performance, and much more.

This article will bring you up to speed on the best nitric oxide boosters and how they work.

Pre-Workouts vs. Nitric Oxide Supplements

These days, pre-workout powders and nitric oxide supplements all seem to be carbon copies of one another. If you don’t believe that, just take a stroll through your local supplement store and browse the pre-workout section. You’ll quickly notice that each product contains very slight variations of the same ingredients.

Unfortunately, many of those pre-workouts are "concentrated" formulas that induce a slight rush of "pseudo-energy” from harsh stimulants. It’s no wonder some people feel like such pre-workouts “work.” (Granted, you could achieve a similar and more cost-effective outcome by chugging a pot of coffee before you hit the gym, but we digress...)

The conundrum with stim-heavy pre-workout formulas is that pretty much anything that stimulates the nervous system is going to constrict blood vessels, increase blood pressure, and counteract nitric oxide production. It's certainly okay to consume some caffeine before training, but ingesting large doses of stimulants will undoubtedly attenuate the benefits of nitric oxide supplements.

Keep that in mind as we take a deeper look at the science underlying the best nitric oxide supplements.

The Five Best Nitric Oxide Supplements

The nitric oxide boosters mentioned below will take your exercise performance and muscle pumps to the next level. Even better, taking these nitric oxide supplements can help lower blood pressure, treat erectile dysfunction (in men), increase blood flow, and promote heart health. Read on as we break down the science and research behind the best nitric oxide supplements:

1. L-Citrulline

L-Citrulline is an amino acid found mainly in the rind of watermelons. In humans, it is an important intermediate in the urea cycle and a biomarker of gastrointestinal function.

Studies show that L-citrulline works to enhance nitric oxide cell signaling [1]. Further research demonstrates that supplementing with L-citrulline before a workout can considerably elevate blood arginine levels and, by extension, nitric oxide production [2]. 

Other advantages of L-citrulline supplementation may include [3]:

• Improving the usage of branched-chain amino acids during exercise

• Reducing muscle protein breakdown in the fasted state

• Enhancing the body’s capacity to eliminate toxins

• Increasing human growth hormone (HGH) secretion, especially after resistance training

Being one of the most popular nitric oxide supplements, L-citrulline is often found in pre-workout formulas. However, most supplements use a form known as L-citrulline malate (which is less potent per gram compared to pure L-citrulline).

An effective dosage of pure L-citrulline is upwards of six grams taken shortly before exercise. Therefore, if you use a pre-workout supplement that contains two grams of 2:1 L-citrulline malate per serving, you’re actually ingesting less than one gram of L-citrulline (which is unlikely to significantly increase nitric oxide production). Keep this in mind before you purchase nitric oxide supplements with low doses of citrulline (malate).

2. Arginine Nitrate

L-arginine supplements have traditionally been the go-to for increasing nitric oxide production. Why is that, you ask? Well, L-arginine and L-citrulline are the integral amino acids that form nitric oxide in the body.

But in contrast to citrulline, arginine is not readily stored in the kidneys. Hence, citrulline is the de facto "reservoir" of endogenous arginine [4]. This is one reason L-citrulline is thought to be superior to L-arginine supplements.

However, L-arginine nitrate provides a distinct advantage over other nitric oxide supplements because it targets two essential nitric oxide-producing pathways, namely the arginine-nitric-oxide-synthase pathway and the nitrate-nitrite-nitric-oxide pathway [5].

In turn, arginine nitrate is effectively a "dual-action" supplement that can rapidly boost nitric oxide levels. And as you'll learn shortly, combining this ingredient with vitamin C produces even more nitric oxide [6].

3. Reduced Glutathione

Glutathione is a tripeptide made up of the amino acids glutamate, glycine, and cysteine; it is arguably the most important endogenous antioxidant in humans. Numerous studies show that glutathione, particularly in the reduced form, mitigates oxidative stress in virtually every body system [7].

Moreover, recent findings suggest that glutathione is an important regulator of nitric oxide levels in endothelial tissue (the thin layer of cells that lines the inside of your blood vessels and heart) [8]. Given that glutathione improves nitric oxide bioavailability, it confers putative synergy with other nitric oxide supplements like L-citrulline and arginine nitrate.

4. Nitrosigine®

Nitrosigine® is another "advanced" form of L-arginine with purported advantages over standard L-arginine supplements. Specifically, Nitrosigine® is a patented form of L-arginine silicate, which allegedly has more capacity to increase nitric oxide production than pure L-arginine.

There are several proposed pathways that Nitrosigine® works through to bolster nitric oxide levels and blood flow. One of the central mechanisms is altering the family of nitric oxide synthases, enzymes that control nitric oxide levels in the body [9]. Nitrosigine® also appears to improve blood flow by activating specific receptors in endothelial cells [10].

By increasing nitric oxide levels, Nitrosigine® can promote the relaxation and dilation of blood vessels, improvement in insulin sensitivity, and greater nutrient delivery to working muscle tissue. Recent clinical trials also suggest that L-arginine silicate may enhance cognitive function, but these effects remain limited [11, 12].

5. Vitamin C

Vitamin C (ascorbic acid) rounds out our list of the best nitric oxide supplements due to its ability to catalyze the conversion of nitrite to nitric oxide in the stomach [13]. There's also evidence that vitamin C can restore blood flow in microcirculation through several pathways, one of which includes inhibiting inducible nitric oxide synthase [14].

And of course, vitamin C is a ubiquitous antioxidant with a range of other health benefits [15].

Maximize Nitric Oxide Production with TL PUMP

Taking nitric oxide supplements — particularly the ones mentioned above — can make a big difference not only in the gym but for overall health and wellness.

The good news is you don't need to buy tons of nitric oxide-related supplements to elevate blood flow and boost nitric oxide levels: Transparent Labs PUMP contains a non-stimulant, nitric oxide boosting formula that will help you maximize blood flow every training session. The ingredients in PUMP increase nitric oxide naturally so athletes and gym-goers can achieve greater muscle pumps and optimize nutrient delivery to working muscle tissue.

PUMP is a versatile pre-workout powder stackable with other nitric oxide supplements, like TL Nitric Oxide Capsules. And remember, don't get too carried away with your caffeine and stimulant intake when taking nitric oxide supplements.