How Quercetin Boosts Heart Health

Cardiovascular disease is the leading cause of death worldwide.¹

Scientists have long known that a diet rich in plant-derived compounds called flavonoids correlates with a reduced risk of cardiovascular diseases.²

Quercetin is one of the most common flavonoids.³

Research shows that it supports heart health in multiple ways, reducing mechanistic factors for cardiovascular disorders and displaying cardio- protective properties.^3,4

In human studies, quercetin:

• Lowered blood pressure,^5-7
• Reduced total cholesterol⁸ and oxidized LDL cholesterol,⁹
• Lowered markers of chronic inflammation tied to cardiovascular disease,^8,10,11
• And more.

These actions can help improve heart health and reduce risk for heart disease.

Cardiovascular Risk Factors

Risk factors for cardiovascular disease include obesity, poor diet, smoking, high blood pressure, high blood glucose, elevated triglycerides, high apolipoprotein B that indicates greater numbers of circulating atherogenic particles such as small dense LDL, and low HDL (“good”) cholesterol.¹²

Any one of the above factors can cause occlusion of arteries feeding the heart, brain and other tissues.

Identifying and managing these risk factors can significantly lower the chance of developing cardiovascular disease and reduce the risk of complications such as fatal heart attacks and strokes in those who already have it.¹²

Quercetin Protects the Heart

Flavonoids are compounds found in plant foods like fruits, vegetables, and whole grains. They have properties that are known to help protect the heart.²

Quercetin is one of the most potent flavonoids. It is found in onions, apples, tea, citrus fruits, and red wine.¹³

It has a long list of benefits, including anti-cancer activity, blood glucose control, and many different actions that support heart health.^3,14

Chronic inflammation and oxidative stress are drivers of most chronic illnesses, including cardiovascular disease. They contribute to the development and progression of atherosclerosis (the buildup of plaque in blood vessels) and to degenerative changes in the heart.¹⁵

As an antioxidant/anti-inflammatory, quercetin protects against this damage.^3,4

Quercetin has been shown to improve other cardiovascular risk factors in preclinical and clinical studies:

• Reducing blood pressure,^5,6
• Activating key metabolic pathways, such as AMPK, which enhance metabolism and help reverse insulin resistance,^16-18
• Supporting endothelial function,¹⁹
• Improving blood glucose control,²⁰
• Reducing plaque-promoting adhesion molecules, protecting blood vessel function, and helping to prevent clot formation,^21,22
• Blocking the formation of oxidized LDL, a major driver of vascular damage in blood vessels and plaque formation and growth,²⁰
• Reducing inflammation and oxidative stress,²³ and
• Decreasing liver fat accumulation.²⁴

What Human Studies Show

A meta-analysis of 39 population studies found that higher flavonoid intake is associated with lower cardiovascular risk.²

When researchers looked at specific flavonoids, they found that quercetin intake was associated with reduced risk of coronary heart disease,² which occurs when the arteries do not deliver enough oxygen-rich blood to the heart. This is the most common type of heart disease.²⁵

Clinical studies have shown the benefits of quercetin. For example, quercetin intake (ranging from 150 mg to 1,000 mg daily) has been shown to lower blood pressure.^5-7,26 Human studies have also shown that quercetin intake improves abnormal lipid levels^.8,9,27

In a randomized, placebo-controlled crossover trial of overweight adults with metabolic risk factors, 150 mg of quercetin daily raised blood levels of the compound and led to small but significant reductions in systolic blood pressure and oxidized LDL, an atherogenic marker. These benefits occurred without adverse effects.⁹

One meta-analysis of human trials found that quercetin supplementation reduced both systolic and diastolic blood pressure. In individuals who took quercetin for more than eight weeks, it also lowered triglycerides and raised HDL (“good”) cholesterol.⁵

Other trials have shown that quercetin intake can lower markers of systemic chronic inflammation tied to cardiovascular disease.^8,10,11 Some of this effect is a result of quercetin’s ability to inhibit activity of NF-kB (nuclear factor-kappa B), a protein complex that produces pro-inflammatory compounds.¹⁰

A systematic review and meta-analysis of human studies found that quercetin reduced total cholesterol, LDL (“bad”) cholesterol, and C-reactive protein (a marker of systemic inflammation) among patients with metabolic disease.⁸

Quercetin doesn’t just reduce risk factors for cardiovascular disease. It also improves heart function itself.

What You Need To Know

Quercetin’s Cardiovascular Benefits

• Cardiovascular disease is the leading cause of death worldwide.
• Risk factors for heart disease include high blood pressure, abnormal cholesterol levels, elevated blood glucose, obesity, poor diet, and smoking.
• Quercetin is a flavonoid found in fruits, vegetables, and herbs. It supports heart health by multiple mechanisms.
• In human studies, quercetin reduced high blood pressure, lowered LDL cholesterol, raised HDL cholesterol, and reduced markers of chronic inflammation, all of which help lower the risk of developing cardiovascular disease, and of cardio-vascular incidents.
• Quercetin also improved heart function in people with a history of heart disease or metabolic risk factors.

In a 12-month controlled trial in patients being treated for gout and high blood pressure (which are both associated with increased risk of heart disease), the addition of quercetin to standard therapy improved heart function and normalized blood pressure.²⁸

In another study, quercetin intake improved the heart function of patients with a history of coronary artery disease.²⁹ Electrocardiogram monitoring in these individuals found fewer episodes of cardiac ischemia (reduction of blood flow to the heart) and of abnormal heartbeats.

These and other studies show that quercetin can reduce risk factors for heart disease and improve heart function.

Summary

Increased intake of flavonoids, compounds found in many plant foods, is associated with lower risk of cardiovascular disease.

Quercetin, one of the most potent flavonoids, supports heart health by multiple mechanisms, including lowering blood pressure, improving lipid levels (reducing LDL, increasing HDL), reducing markers of chronic inflammation, protecting blood vessels, and improving heart function.

Human studies show that quercetin intake can reduce cardiovascular risk factors and improve heart function in people with or at risk for heart 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.

Fenugreek Seed Fibers Help Boost Quercetin Bioavailability

Flavonoids like quercetin suffer from poor bioavailability, but scientists have found that when combined with fenugreek seed fibers, bioavailability improves tremendously.

In one clinical study, researchers compared a fenugreek-quercetin formulation to unformulated quercetin. They found that formulated quercetin delivered up to 62 times greater bioavailability compared to unformulated quercetin.³⁰

References

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