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What are bioflavonoids?

Bioflavonoids are a group of what are called “polyphenolic” plant-derived compounds. They’re also called flavonoids. There are between 4,000 and 6,000 different varieties known. Some are used in medicine, supplements, or for other health purposes.

Bioflavonoids are found in certain fruits, vegetables, and other foods, like dark chocolate and wine. They have potent antioxidant power.

Why is this so interesting? Antioxidants may fight free radical damage. Free radical damage is thought to play a part in anything from heart disease to cancer. Antioxidants may even help your body deal with allergies and viruses.

Bioflavonoids are antioxidants. You may already be familiar with antioxidants, such as vitamins C and E and carotenoids. These compounds may protect your cells from free radical damage. Free radicals are toxins in the body that can damage healthy cells. When this happens, it is called oxidative stress.

Other antioxidants, like flavonoids, may not be found in high concentrations in the bloodstream alone. But they may affect the transport or activity of more powerful antioxidants, like vitamin C, throughout the body. In fact, some supplements you’ll find at the store contain both vitamin C and flavonoids together for this reason.

Antioxidant power

Researchers share that bioflavonoids may help with a number of health issues. They have the potential to be used therapeutically or protectively. Flavonoids may also influence the ability of vitamin C to be absorbed and utilized by the body.

The antioxidant power of flavonoids is well documented in different studies. In one overview, researchers explain that antioxidants like flavonoids work in a variety of ways. They can:

  • interfere with the enzymes that create free radicals, which suppresses reactive oxygen species (ROS) formation
  • scavenge free radicals, meaning they deactivate these bad molecules before they cause damage
  • protect and even increase antioxidant defenses in the body

When antioxidants stop free radicals in their tracks, cancer, aging, and other diseases may be either slowed or prevented.

Allergy-fighting potential

Allergic diseases may respond well to taking in more bioflavonoids. This includes:

Development of allergic diseases is often associated with excess oxidative stress on the body. Flavonoids may help to scavenge free radicals and stabilize the reactive oxygen species. This can lead to fewer allergic reactions. They may also reduce inflammatory responses that contribute to diseases like asthma.

So far, the research has suggested that flavonoids — along with improved diet habits — show potential for fighting allergic diseases.

Researchers are still trying to determine exactly how these compounds work. They also need to know how much is effective in preventing or treating these diseases.

Cardiovascular protection

Coronary heart disease (coronary artery disease) is another health issue that involves oxidative stress and inflammation. The antioxidants in flavonoids may protect your heart and lower your risk of death according to one study. Even small amounts of dietary flavonoids may lower the risk of coronary heart disease death. But that research is needed to determine exactly how much of the compound gives the most benefit.

Other research shows that bioflavonoids may lower your risk for both coronary artery disease and stroke.

Nervous system support

Flavonoids may protect nerve cells from damage. They may even help with regeneration of nerve cells outside the brain and spinal cord. Most research has focused on chronic diseases thought to be caused by oxidative stress, such as dementia due to Alzheimer’s disease. In these cases, flavonoids may help delay onset, especially when taken long term.

Flavonoids may also help with blood flow to the brain. This may help to prevent stroke. Better blood flow may also mean better brain function or even improved cognitive function.

Other uses

In another study, researchers explored how the flavonoids orientin and vicenin may help the body repair after injury from radiation. The subjects in this study were mice. The mice were exposed to radiation and later given a mixture containing the bioflavonoids. In the end, the bioflavonoids proved to be efficient at scavenging the free radicals produced by radiation. They also were associated with faster DNA repair in cells that had been damaged.

Flavonoids and detoxification is another subject being explored in the research community. Some even believe that flavonoids may help clear the body of toxins that lead to cancer. Studies on animals and isolated cells support these claims. Unfortunately, those on humans have not consistently shown that flavonoids do much to reduce cancer risk. Flavonoids potentially have a role in lowering one’s risk for cancer, including breast and lung cancers.

Finally, bioflavonoids may have antimicrobial properties as well. In plants, they’ve been shown to help fight microbial infection against different microorganisms. In particular, bioflavonoids like apigenin, flavone, and isoflavones have been shown to have potent antibacterial properties.

Research note

It’s important to note that many studies on bioflavonoids to date have been in vitro. This means they are performed outside of any living organism. Fewer studies have been performed in vivo in human or animal subjects. More research is needed on humans to back any associated health claims.

The United States Department of Agriculture has estimated that in the United States, adults generally consume 200–250 mg of bioflavonoids each day. While you can purchase supplements at your local health food shop or pharmacy, you may want to look in your refrigerator and pantry first.

For example, among some of the largest sources of flavonoids in the United States are green and black tea.

Other food sources include:

  • almonds
  • apples
  • bananas
  • blueberries
  • cherries
  • cranberries
  • grapefruit
  • lemons
  • onions
  • oranges
  • peaches
  • pears
  • plums
  • quinoa
  • raspberries
  • strawberries
  • sweet potatoes
  • tomatoes
  • turnip greens
  • watermelon

When reading labels, it’s helpful to know that bioflavonoids are divided into five subcategories.

  • flavonols (quercetin, kaempferol, myricetin, and fisetin)
  • flavan-3-ols (catechin, epicatechin gallate, gallocatechin, and theaflavin)
  • flavones (apigenin and luteolin)
  • flavonones (hesperetin, naringenin, and eriodictyol)
  • anthocyanidins (cyanidin, delphinidin, malvidin, pelargonidin, peonidin, and petunidin)

Currently, there is no Dietary Reference Intake (DRI) suggestion for flavonoids from the National Academy of Sciences. Similarly, there is no Daily Value (DV) suggestion from the Food and Drug Administration (FDA). Instead, many experts suggest eating a diet rich in healthy, whole foods.

Supplements are another option if you’re interested in consuming more bioflavonoids, though many people are able to get enough of these antioxidants with a diet rich in whole fruits and vegetables.

Fruits and vegetables have high concentrations of flavonoids and relatively low risk for side effects. If you are interested in taking herbal supplements, it’s important to remember that these compounds are not regulated by the FDA. Be sure to purchase these items from reputable sources, as some may be contaminated with toxic materials or other drugs.

It’s always a good idea to call your doctor or pharmacist before starting any new supplements. Some may interact with certain medications. Pregnant or nursing women should also be sure to check with a medical professional before starting any new supplements.

Bioflavonoids may have the potential to help with heart health, cancer prevention, and other issues related to oxidative stress and inflammation, like allergies and asthma. They are also readily available in a healthy diet.

The fruits, vegetables, and other foods rich in flavonoids are high in fiber and vitamins and minerals. They are also low in saturated fats and cholesterol, making them good food choices for your overall health.