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Quercetin in Apples, Berries, Red Onions Increases Exercise Stamina


Apples, long considered just the thing the doctor ordered, appear to be ready for an upgrade. A recent study by Dr. J. Mark Davis at the University of South Carolina reveals that quercetin, an active ingredient in apples, can increase stamina during exercise—even in people not categorized as regular exercisers. 

The quercetin afforded significantly greater increases in peak oxygen consumption for the dozen volunteers in the study taking it in a purified supplement form, compared to a control group taking a placebo.

Researchers are clear that fruits and vegetables contain plant substances that can protect against major illnesses such as heart disease and cancer. It’s one reason for the U.S. federal recommendation that people get nine servings daily and not the former standard of five.

The results were reported in the August issue of the International Journal of Sport Nutrition and Exercise Metabolism.

"These data suggest that as little as seven days of quercetin supplementation can increase endurance without exercise training in untrained subjects," the researchers said.

The research is preliminary and needs confirmation, said Davis. A major question is if quercetin in supplement form can be as potent and effective as it appears to be in plant food itself.

In addition to apples, Quercetin is also found in red onions, berries and grapes. It is classified as a flavonoid and gives some fruits and veggies its red pigment.

Quercetin belongs to a group of plant pigments called flavonoids that give many fruits, flowers, and vegetables their color. Other studies have pegged it as helping to reduce LDL or bad cholesterol that unchecked can lead to heart disease.

Bob Condor blogs for Alternative Health Journal every Monday, Tuesday, Thursday, Friday and Saturday. 




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