Boost Nitric Oxide to Reduce Cardiovascular Risk

Nitric oxide is a substance your body naturally produces.

It signals blood vessels to widen, allowing blood to flow through freely.

But nitric oxide production decreases with age.¹

This contributes to endothelial dysfunction that leads to the initiation and progression of arterial disease.^2-5

The consequences of endothelial dysfunction are:

1. Diminished circulation
2. High blood pressure
3. Thrombosis
   (clots inside blood vessels)
4. Atherosclerosis

These are major causes of stroke and heart attack.^5-8

We can’t get nitric oxide directly from diet or supplements.

The good news is that L-arginine and aronia berries help the body make more of it.

Endothelial Dysfunction and Cardiovascular Disease

The endothelium is the inner lining of blood vessels, and it plays a critical role in regulating the flow of blood.^2-4

It does this by producing nitric oxide, which signals blood vessels to dilate (widen). That allows greater blood flow to tissues, including the heart and brain.

But as we age, our body makes less nitric oxide.¹ That can lead to endothelial dysfunction, which means the blood vessels are unable to dilate and constrict as needed, reducing blood flow.^2-4

This condition, referred to as arterial stiffness, contributes to high blood pressure, formation of atherosclerotic plaque, and inflammation in the arteries—all of which can lead to cardiovascular disease.⁹

It also greatly increases the risk of abnormal clotting, which can block blood vessels, leading to heart attack, stroke, and sudden cardiac death.^10,11

Endothelial dysfunction is surprisingly common; one study showed it affected about one third of people without any prior history of cardiovascular disease.¹² The elderly, diabetics, the obese, smokers, people with cardiovascular disease, and those with high cholesterol or high blood pressure have a higher risk.^2-4

But if we can increase the amount of nitric oxide in our blood vessels, it may stop, and even reverse endothelial dysfunction.

How L-Arginine Helps

Unfortunately, we can’t simply take nitric oxide as a supplement. It has an extremely short half-life, which means it’s too quickly metabolized and eliminated from the bloodstream to be useful.

To work properly, blood vessels must make nitric oxide for themselves. To do so, they need a precursor compound. This precursor is an amino acid called L-arginine.

Aware of this link between L-arginine and nitric oxide production, researchers evaluated whether increasing intake of L-arginine improves blood vessel dilation, lowering risk for disease.^13-17

One of the main ways to test this is to measure how much a blood vessel widens in response to an increase in blood flow, something called flow-mediated dilation.

In a landmark clinical trial published in the International Journal of Cardiology, scientists gave patients with high blood pressure a single dose of either L-arginine or a placebo.¹⁵ While the placebo group had no change in their blood vessel function, those receiving L-arginine had an improvement in their flow-mediated dilation from an average of 1.7% to 5.9%.

Considering that each 1% improvement in flow-mediated dilation correlates with a 12% lower risk of cardiovascular events like heart attacks and strokes,^18,19 this would suggest a 50% reduction in risk of cardiovascular events if the effect is sustained over time.

Other longer-term clinical studies have shown that taking L-arginine can lower blood pressure and reduce symptoms associated with coronary artery disease.^16,20

A New, Better Form of L-Arginine

Life Extension® has written about L-arginine for the past 38 years. But in the last few years, scientists have developed and tested a new form.

Known as inositol-stabilized arginine silicate, this novel form is more bioavailable, which means more of it is absorbed into the bloodstream after ingestion.

Studies show that L-arginine blood levels increase within one hour after supplementation with inositol-stabilized arginine silicate and stay there for many hours.^21,22

It appears to do this by inhibiting the enzyme arginase, which breaks down L-arginine in the digestive tract, allowing more of the L-arginine to enter and circulate in the blood longer.²³

Aronia Berry Improves Endothelial Function

Aronia berries are small, dark purple berries native to North America. They’re high in anthocyanins, beneficial polyphenols.

Scientists discovered that like L-arginine, aronia can improve endothelial function.

While L-arginine provides the precursor needed to form nitric oxide, polyphenols from aronia berries appear to increase the activity of the enzyme that converts the L-arginine into nitric oxide.

It does this by inducing the modification of the enzyme, called endothelial nitric oxide synthase, in a way that turns the enzyme “on.”²⁴

In one randomized, controlled trial, daily supplementation with 500 mg of aronia whole fruit berry for 12 weeks resulted in improved flow-mediated dilation.²⁵ Subjects taking the aronia had a 0.9% improvement in flow-mediated dilation compared to those taking a placebo.

That may sound small, but bear in mind that each 1% improvement in flow-mediated dilation correlates with a 12% lower risk of cardiovascular events,^18,19 suggesting that this corresponds to a nearly 11% reduction in risk for cardiovascular events.

The enhanced bioavailability of inositol-stabilized arginine silicate coupled with the increased endothelial nitric oxide synthase activity from aronia berries make this a potent duo in the production of nitric oxide.

Summary

Our bodies produce nitric oxide, which signals blood vessels to dilate. With age, its production declines, contributing to endothelial dysfunction.

Endothelial dysfunction increases the risk of cardiovascular disease, including heart attacks and strokes.

Two ingredients, L-arginine and aronia berries, boost the body’s production of nitric oxide.

Human studies show that they improve the flow of blood through the vessels, which can reduce the risk for cardiovascular disease.

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.

References

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