“Vitamin P” is a historical term, now more accurately known as bioflavonoids. These compounds are widely present in fruits, vegetables, and other plant-based foods. Bioflavonoids are not true vitamins, as they are not considered essential nutrients the human body cannot produce on its own. They are recognized for their diverse roles in plant biology and potential health connections in humans.
What Are Bioflavonoids?
Bioflavonoids are a large family of polyphenolic compounds produced by plants. Over 5,000 types have been identified. The historical term “vitamin P” is no longer accurate because bioflavonoids are not essential for life in the same way that vitamins like A, C, or D are. They are secondary metabolites, meaning plants produce them for various functions, such as attracting pollinators or protecting against environmental stressors.
These compounds are broadly classified into several subgroups based on their chemical structure, including flavones, flavonols, flavanones, flavanols, isoflavones, and anthocyanidins. Common examples include quercetin found in onions, genistein in soy, and rutin, often associated with citrus fruits. The terms “flavonoid” and “bioflavonoid” are often used interchangeably.
Where to Find Bioflavonoids
Bioflavonoids are abundant in a wide variety of plant-based foods. Fresh fruits, especially citrus fruits, berries, and tree fruits, are excellent sources. Citrus fruits like lemons, oranges, and grapefruits contain bioflavonoids such as hesperidin and naringin, often concentrated in the peel and white pith. Berries like strawberries, grapes, and blueberries are rich in various bioflavonoids, including anthocyanins.
Many vegetables also provide these compounds, including broccoli, kale, and red onions. Teas, particularly green and black tea, and dark chocolate are notable sources. Consuming a varied diet rich in colorful fruits and vegetables is the most effective way to obtain bioflavonoids.
How Bioflavonoids Work
Bioflavonoids exert their effects primarily through their antioxidant and anti-inflammatory properties. As antioxidants, they help neutralize unstable molecules called free radicals, which can cause cellular damage. This protects cells and tissues from oxidative stress.
Bioflavonoids also exhibit anti-inflammatory effects by modulating pathways involved in the body’s inflammatory response. They can influence cell signaling and enzyme activity, regulating inflammation. Some bioflavonoids, such as rutin, may also support blood vessel integrity and enhance vitamin C’s action by inhibiting its breakdown. This synergistic relationship with vitamin C is often observed where they are found together in foods.
Health Connections
Research suggests that dietary intake of bioflavonoids is associated with various health connections, particularly due to their antioxidant and anti-inflammatory actions. They contribute to cardiovascular health by supporting blood vessel function, reducing inflammation, and influencing cholesterol metabolism. Citrus flavonoids may improve vascular endothelial function and reduce platelet activity.
Bioflavonoids are also linked to immune system support, as their anti-inflammatory and antioxidant properties bolster the body’s defenses. For skin health, bioflavonoids may protect against environmental damage, support collagen production, and reduce signs of aging. Specific bioflavonoids like quercetin, hesperidin, and rutin have been studied for their potential to nourish skin cells. Some research indicates benefits for brain health, with certain flavanols improving brain function and blood flow.
Considering Bioflavonoid Supplements
While bioflavonoids offer health benefits, they are not classified as essential vitamins, so there is no established recommended daily intake. A balanced diet rich in diverse fruits, vegetables, and other plant foods generally provides sufficient amounts. It is healthiest to obtain bioflavonoids from dietary sources rather than relying on supplements.
If considering bioflavonoid supplements, consult a healthcare professional. Supplements are not always regulated like medications, and their exact source or types of bioflavonoids may not be clear. Some bioflavonoids may interact with certain medications.