Quercetin belongs to a class of molecules called flavonoids that are naturally present in some plants. Flavonoids are strong antioxidants, which destroy damage-causing free radical molecules that can lead to a number of health problems. One health problem that people take quercetin to treat is high cholesterol, which can lead to heart and blood vessel disease.
How It Works
Two types of cholesterol exist in the body: low-density lipoprotein, or LDL, and high-density lipoprotein, or HDL. LDL is often called "bad" cholesterol, because this is the type of cholesterol that becomes deposited in and damages blood vessels. Free radicals can cause damage to LDL cholesterol, making this type of cholesterol more likely to cause heart disease. The University of Maryland Medical Center therefore notes that combating free radicals and preventing the damage to LDL are the likely mechanisms by which quercetin reduces the detrimental effects of cholesterol.
Dosage
The NYU Langone Medical Center notes that the normal therapeutic dose of quercetin is between 200 and 400mg taken three times each day. As of 2011, more research is needed to determine a specific link between quercetin and cholesterol, but evidence does exist that flavonoids in general help lower blood cholesterol. Additionally, studies have found that people who take flavonoids and a red wine extract have less damaged LDL cholesterol.
Note of Caution
The University of Maryland Medical Center warns people not to take more than 1g of quercetin each day because some people taking more than this amount have reported damage to the kidneys. Additionally, there is a chance that taking quercetin can raise your risk of getting cancer. Check with your doctor before taking quercetin to make sure it is safe for you.
Sources
To reduce the damage to your body caused by cholesterol by taking quercetin, ingest at least one of several sources of this nutrient. Quercetin exists in high amounts in several different foods, including citrus fruits like oranges and lemons; certain beverages, including red wine and tea; onions and apples. Other foods that contain moderate amounts of quercetin are certain berries, like blueberries and blackberries, olive oil and grapes. You can also find this supplement in capsule or pill form.
