305-Life and Dr. Sanaz Hariri believe that knowledge is power. We are excited to share our insights with you in hope that they will inspire you on your journey of movement, joy and health.
April 2022 Post
What is quercetin?
An organic compound always contains carbon (inorganic compounds do not contain carbon). A phenol is an organic aromatic (i.e. ring) compound composed of a benzene ring (6 carbons) with a hydroxyl group (-OH) substitution. The chemical formula of a phenol is therefore HO-C6H5. Polyphenols are composed of more than one phenol. There are thousands of polyphenol groups. The major polyphenol groups are: (1) flavonoids (~60% of all polyphenols, include quercetin), (2) phenolic acids (~30% of all polyphenols, including stilbenes and lignans) and (3) polyphenolic amides (including capsaicinoids found in chili peppers). Quercetin is a flavonoid (subclass: flavonol).
Flavonoids are plant compounds that have a flavone backbone: a three ringed molecule with hydroxyl [OH] groups attached. Flavonols are either glycosides [have a glycosyl (sugar) group attached] or aglycones (no attached sugars). Quercetin is an aglycone. Quercetin glycoside has a glycosyl (sugar) group attached. Most dietary intake of quercetin is in the form of quercetin glycoside.
Quercetin is a phytochemical. Phytochemicals are compounds made by plants ("phyto" means "plant"). Quercetin is found in many foods, including apples, berries, grapes, onions, shallots, tomatoes, seeds, and nuts. Quercetin is also found in beverages such as red wine, black tea, and green tea. Growing conditions affect the concentration of quercetin in foods. For example, organically grown tomatoes have a significantly higher quercetin contact compared to conventionally grown tomatoes.
Antioxidant
An antioxidant inhibits oxidation. Oxidation occurs when electrons are lost (reduction occurs when electrons are gained). When a molecule is missing an electron (when it is oxidized), it becomes a highly reactive unstable molecule called a “free radical.” Free radicals attack nearby molecules to steal an electron, damaging nearby structures. When food is metabolized, free radicals are formed. Oxidative stress is a state when free radicals outnumber antioxidants. Free radicals play a role in cancer (by damaging DNA), heart disease, stroke, and the general process of aging.
Quercetin is an antioxidant, inhibiting the production of free radicals and scavenging free radicals. This antioxidant effect can protect the brain, heart, and other vital tissues.
Diabetes
Quercetin has been found to lower blood glucose levels, help preserve pancreatic beta-cell integrity and function (the cells that make insulin), and decrease symptoms of diabetic neuropathy.
Aldose reductase is an enzyme that catalyzes the conversion of glucose to sorbitrol. This reaction plays an essential role in the formation of diabetic cataracts. Quercetin inhibits aldose reductase in the lens, thereby inhibiting sorbitol accumulation in the lens and delaying onset of diabetes-induced cataracts.
Anti-inflammatory/Anti-Allergy Effect
Quercetin inhibits inflammation-producing enzymes such as such as cyclooxygenase (COX) and lipoxygenase (LOX). Anti-inflammatory medications such as ibuprofen and naproxen also work by inhibiting COX. Quercetin has antinociceptive (pain-relieving) effects by inhibiting pronociceptive cytokine production and free radical generation that causes inflammatory pain. In patients with osteoarthritis, quercetin decreases pain symptoms and increases daily activities such as walking and going up and down stairs.
Quercetin inhibits histamine release from mast cells and basophils. White blood cells, such as eosinophils and neutrophils, promote inflammation. Inflammation can help control disease, but when the inflammation is greater than necessary, inflammation can cause troublesome symptoms and even tissue damage. Quercetin reduces eosinophil and neutrophil counts and infiltration in lung tissue and inhibits asthmatic reactions.
The Future
These are only a few of the many amazing and promising potential health benefits of quercetin. The data we have on quercetin is mostly based on studying its general pharmacokinetics and animal studies. More human clinical studies are needed to show how these basic and animal science discoveries specifically pertain to us.
March 2022 Post
Resveratrol: The Basics
The French Paradox
The French enjoy rich foods high in saturated fats, yet they have lower rates of heart disease – this is known as the “French paradox.” How is this possible? Regular and moderate wine consumption may explain the relative immunity of the French to ischemic heart disease. Resveratrol (found in red wine) is postulated to be one of the keys. Resveratrol has many benefits including: antioxidant, anti-inflammatory, and cardioprotective effects described below.
What is resveratrol?
An organic compound always contains carbon (inorganic compounds do not contain carbon). A phenol is an organic aromatic (i.e. ring) compound composed of a benzene ring (6 carbons) with a hydroxyl group (-OH) substitution. The chemical formula of a phenol is therefore HO-C6H5. Polyphenols are composed of more than one phenol. There are thousands of polyphenol groups. The major polyphenol groups are: (1) flavonoids (~60% of all polyphenols, include quercetin), (2) phenolic acids (~30% of all polyphenols, including stilbenes and lignans) and (3) polyphenolic amides (including capsaicinoids found in chili peppers). Resveratrol and curcumin (in turmeric) are polyphenols. Resveratrol possesses two phenol rings linked by two carbons (an ethylene bridge).
Resveratrol is a phytochemical. Phytochemicals are compounds made by plants ("phyto" means "plant"). Phytoalexins are phytochemicals produced by plants to combat attacks. Plants such as grapes, peanuts, and some berries produce the phytoalexin resveratrol. Mechanical injury, UV irradiation, and fungal attacks spur plants to produce resveratrol. Grapes likely have high resveratrol levels as a response to attacks by fungi. Resveratrol is most concentrated in the skins and seeds of grapes – the parts of the grapes used in red wine fermentation. Resveratrol is present in concentrations of 0.1-14.2 mg/L in red wine.
Antioxidant
An antioxidant inhibits oxidation. Oxidation occurs when electrons are lost (reduction occurs when electrons are gained). When a molecule is missing an electron (when it is oxidized), it becomes a highly reactive unstable molecule called a “free radical.” Free radicals attack nearby molecules to steal an electron, damaging nearby structures. When food is metabolized, free radicals are formed. Oxidative stress is a state when free radicals outnumber antioxidants. Free radicals play a role in cancer (by damaging DNA), heart disease, stroke, and the general process of aging. Resveratrol is a powerful antioxidant, inhibiting the production of free radicals and scavenging free radicals.
Cardioprotective
Resveratrol protects the cardiovascular system. Resveratrol promotes the production of nitric oxide, which relaxes the muscles in the walls of arteries. In the presence of nitric oxide, the arteries are not as stiff, decreasing the pressure exerted on arterial walls when the heart beats. The pressure from a heartbeat on arterial walls is called systolic blood pressure (the upper number in a blood pressure reading). Decreasing systolic blood pressure decreases the risk for heart disease. The heart does not need to work as hard to pump out the blood when the arteries are less stiff. Arteries that are under less pressure sustain less damage. Resveratrol also inhibits platelet aggregation, possibly decreasing risk of blood clot formation and their sequelae, such as myocardial infarctions (MI’s or “heart attacks”) and strokes. Resveratrol also decreases total cholesterol levels.
Anti-inflammatory
Inflammation is the body’s natural response to infection and injury. When tissue is injured, the enzyme COX (cyclooxygenase) converts arachidonic acid to prostaglandins. Prostaglandins are lipids that spark inflammation, causing symptoms such as swelling, pain, and fever. Prostaglandins stimulate blood clots and blood vessel wall contractions. Inflammation is part of our natural healing response. However, inflammation is also involved in arthritis, cancer, painful menstrual bleeding, and stroke. Common anti-inflammatories such as ibuprofen, naproxen, and celecoxib function by inhibiting COX. Resveratrol also inhibits cyclooxygenases (COX), thereby inhibiting inflammation.
The future
These are only a few of the many amazing and promising potential health benefits of resveratrol. The data we have on resveratrol is mostly based on studying the general pharmacokinetics of resveratrol. More human clinical studies are needed to show how these basic and animal science discoveries specifically pertain to us.
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