In this issue of Alternatives and in many previous ones, I’ve discussed the importance of flavonoids in the diet. A new study further supports this idea. Researchers at the National Institute of Public Health and Environmental Protection in Bilthoven, Netherlands have found that the risk of dying from coronary heart disease (CHD) is reduced dramatically when the diet contains more flavonoids.
In 1985, the daily intake of flavonoids was monitored in 805 men aged 65 to 84. The men were followed for five years. According to flavonoid intake, the men fell into roughly three equal groups: those who consumed around 19 grams a day, those who averaged around 29 grams, and those who averaged 79 or more grams daily. The major sources for flavonoids were black tea (61% of flavonoid intake), onions (13%) and apples(10%).
During the five year period, 43 men died of coronary heart disease and another 38 experienced their first non-fatal heart attack. The researchers discovered that the men with the highest intake of flavonoids had a 50% lower risk of dying from heart disease or heart attack that those men with the lowest intake.
There are several very interesting and useful tidbits we can learn from this study. A couple could save your life.
First, there will be those who write this study off, saying a high flavonoid intake is simply an indication of a more healthy lifestyle and a diet high in fruits and vegetables and low in fat. But that’s not the case in this study. These researchers adjusted for those factors like physical activity, cholesterol levels and obesity. The only factor that made a difference was the flavonoid intake. And the major portion of the flavonoids didn’t come from fruits and vegetables—61% of them came from tea!
In simple terms, those who consumed four or more servings (four ounces per serving) halved their risk of heart disease compared to those who drank little or no tea.
Secondly, based on research performed in the 1970’s, most authorities still believe the average daily intake of flavonoids in the U.S. is in the neighborhood of 1,000 grams a day. Unfortunately, this figure is the result of using techniques we now know are inaccurate (for one, whole foods were analyzed instead of just the edible portions) (World Rev Nutr Diet 76;42. 117-20). Flavonoid consumption in the U.S. would be far less than previously thought if we used the Netherlands’ study technique. It would probably be very close to that found in this study.
This next finding may prove to be the most useful of all. While the researchers analyzed five different flavonoids in these men’s diets, the flavonoid called quercetin (pronounced kwer-see-tin) made up most (63%) of all the flavonoid intake. Quercetin appears to be one of the main keys in cutting the risk of coronary heart disease. This is easier to understand once you take a closer look at quercetin.
As I’ve been reporting for years, it’s not necessarily the cholesterol levels we need to worry about when it comes to heart disease, it’s the amount of LDL (“bad cholesterol”) that oxidizes or goes rancid and damages the lining of the arteries. Well, it just so happens that quercetin has been shown to stop the oxidation of LDL cholesterol. It also reduces the stickiness of platelets in the blood stream which can cause clotting and blockages in blood vessels. Quercetin may also protect your arteries in other ways.
Early work in the 1970’s has led several scientists to believe that the herpes simplex virus type 1 can cause heart and artery disease. (This is the same herpes virus that causes “cold sores” in and around the mouth.) Researchers at Cornell University placed a group of chickens on a cholesterol-free diet. Half the group was then vaccinated against the herpes virus and then all the chickens were infected with the virus. The unvaccinated chickens developed clogging of the heart arteries, while the vaccinated ones remained disease-free.
Dr. David Hajjar, also of Cornell University has continued research along this same line and at the Monterey, California American Heart Association meeting last January told us he felt, “the herpes virus is the missing link between thrombosis and atherosclerosis.” I have little doubt his theory is probably correct. However, the direction in which Dr. Hajjar and his colleague’s research is going is questionable. I think they may be overlooking the idea that there are a long list of items that can trigger atherosclerosis. Viruses are only one of them. Bacteria, trauma, free radicals, toxins from cigarette smoke and oxidized LDL cholesterol are a few of the others. Still, Dr. Hajjar might be able to solve all his problems by taking a closer look at quercetin.
Quercetin inhibits the infectivity of the herpes virus (J AIlergy Clin Immunol 82; 69:104). In other words, it is effective at stopping the herpes virus. This is just one more way it protects against coronary artery disease, atherosclerosis and heart attack.
“Quercetin really seems to shine in the area of allergies and asthma.”
There are several ways to insure you’re getting adequate amounts of bioflavonoids (particularly quercetin).
If you’re a coffee drinker you might try switching to tea instead. Four servings (four ounces each) of black tea was the main source of quercetin in the above study.
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I wouldn’t take up drinking solely for this purpose; however, wine also contains quercetin, particularly red wine. (The quercetin content in wine helps explain what has been called the “French Paradox.” It is thought to be a major reason why people in that country can consume a diet high in fat yet still have a very low risk of heart disease.)
In no way do I want to downplay the importance of being able to prevent heart disease through the use of quercetin. You should be aware, however, that there are several other very important ways this flavonoid can be used to protect your health.
Quercetin really seems to shine in the area of allergies and asthma. Allergic reactions occur when some foreign protein (chemical, pollen, undigested food particle, etc.) enters the bloodstream and triggers the release of histamine and serotonin, which cause coughing, breathing difficulties, clogged sinuses, skin eruptions, etc.
Quercetin stabilizes the walls of the cells that contain histamine and serotonin (mast cells and basophils) and prevents the release of these chemicals.
“Quercetin, at doses of 1,500 to 2,000 mg daily, can often prevent the horrible symptoms associated with allergies.”
Quercetin, at dosages of 1,500 to 2,000 mg daily, can often prevent the horrible symptoms associated with allergies. The dosage should be divided into equal portions and taken throughout the day. [A typical routine would be to take 300 mg of quercetin (and 100 mg of bromelain) with each meal and the same amounts at mid-morning, mid-afternoon and before bedtime.]
Quercetin also has an added benefit for asthmatics. It can block the formation of leukotrienes.
In asthma, some of the more troublesome compounds released are the leukotrienes(LT’s). (Leukotrienes are derived from arachidonic acid, located in the cell membranes.) For those of you not interested in chemistry, these are the vicious little compounds that cause the bronchial tissue in the lungs to constrict, making normal breathing impossible. The same dosages mentioned for allergies have been used effectively for asthmatics.
Quercetin (or a product containing several of the bioflavonoids) may also be helpful if you suffer from problems like: the tendency to bruise easily, stroke, skin ulcerations, varicose veins, hemorrhoids, bleeding ulcers or rheumatoid arthritis.
Many fruits and vegetables contain bioflavonoids. Quercetin in particular, however, is found at higher levels in grapefruit (particularly the white pulp portion), onions, apples, broccoli, shallots and summer squash. It can also be extracted from the quercitron oak tree, the eucalyptus tree and from some forms of blue-green algae.
I’m always in favor of getting essential nutrients from the diet instead of supplements whenever possible. And quercetin is no exception; however, it is difficult to digest, and for someone who is already suffering from either heart disease or one of the other ailments mentioned, taking extra supplement form is often necessary.
For maintenance or as a preventative measure, a mixture of bioflavonoids (200 to 500 milligrams daily) of uercetin (50 to 150 milligrams a day) is the general recommendation. Vitamin C should be taken along with any of the bioflavonoids–t multiplies their effect. Also, the flavonoids bind with copper, eliminating its destructive effect on vitamin C.
It’s not well known, but quercetin can sometimes be hard to assimilate, especially as we get older. The problem can be overcome somewhat, however, by taking the pineapple-derived digestive enzyme bromelain. Taking bromelain in quantities equal to 1/4 to 1/3 the amount of quercetin is usually sufficient. Bromelain has several added bonuses of its own.
Quercetin and the other bioflavonoids are non-toxic. They’re readily available in food or as supplements. And even though this study helps show just how important they are to our survival, don’t expect your doctor or the medical profession to start recommending them. The importance of quercetin will probably become public knowledge 20 or 30 years from now. Ten years after that it might even be accepted by mainstream medicine. Regrettably, that will be too late for the millions of people who will have died needlessly from heart disease. You’ll be way ahead of the crowd if you start including more quercetin in your diet or start taking it as a daily supplement now.
Reprinted from the health newsletter, Alternatives ($39.00/yr. 12 issues), with permission from Mountain Home Publishing, P.O. Box 829, Ingram, TX 78025. Subscription information and/or a sample issue can be obtained by writing to the above address. Illustration used with permission from W.G. Crook, Chronic Fatigue Syndrome and The Yeast Connection, Professional Books, 1992.