Flavonoids for Strong, Healthy VeinsWith vein-support supplements, you can make the skies friendlier to your health

You’re going on a long trip, and you want to make sure that the plane lands in the conventional manner. Being a good citizen, you leave your box cutter and other sharp objects at home when you head for the airport, hoping that everyone else has done the same. Once there, you patiently endure the security procedures, knowing that they’re for your protection. Through good luck, your shoes turn out not to contain any bombs, and your socks have no holes in them. (Did you know that sock sales soared when people started having to take their shoes off at airports?)

Meanwhile, though, you can’t help noticing that a small boy’s baseball cap is removed and inspected for possible concealed weapons or explosives, while grown men wearing similar caps are waved on through. A white-haired old lady is pulled from the line and thoroughly patted down while swarthy young men walk right onto the plane unpatted, and probably amused (or not).

And the federal agent who happens to be booked on your flight (lucky you!) is required to surrender his weapon. No, not his .357 magnum, but the nail clippers he’s also packing. Why? Because . . . well, what if he went berserk and decided to hijack the plane? (Agent to self: “I think I’ll hijack this plane. Let’s see, I’ve got a gun, and I’ve got nail clippers. Which one should I use? Hmm . . .”) So fork over that deadly weapon, pal, and by the way, please keep your gun securely holstered in the upright position.

Don’t laugh—all these things have actually happened at U.S. airports lately. Doesn’t that make you feel more secure?

Pulmonary Embolism Can Ruin Your Whole Day

But I digress. Well, not really, because this article is about airplanes and matters of life and death—yours, if you’re a passenger on a long-haul flight of more than about 5 or 6 hours (or even on a train or bus or car trip of similar duration, if you remain seated the whole time). It’s not about terrorists, though, and no federal agent can protect you from the danger you face. It’s up to you to look out for yourself and protect your health. As you will see, one way to do that is by supplementing with certain flavonoids—natural plant pigments found in flowers, fruits, vegetables, and herbs—that can help hold the danger at bay.

But what is the danger? Two words: pulmonary embolism. That’s medical jargon for an obstruction—usually a detached blood clot—in an artery in one of your lungs. If that occurs, it’s a medical emergency, requiring prompt treatment. In rare cases, there isn’t time for that, however, because the pulmonary embolism is fatal—the victim just drops dead, completely ruining his day. It almost ruined President Nixon’s day once, when he suffered a pulmonary embolism during a flight on Air Force One.

Deep-Vein Thrombosis—Villain of the Skies

So where does a pulmonary embolism originate? In a deep vein in one of your lower legs, most likely. When a blood clot forms there, it’s called a deep-vein thrombosis.Thrombosis means the formation, or the mere presence, of a blood clot, which is never a good thing except at a wound site, where it’s necessary to stop the bleeding.

As long as the clot stays in the blood vessel where it formed, it’s a called a thrombus(from the Greek word for clot). When it finally detaches, however, and gets swept along with the blood flow, it’s called an embolus (from the Greek word for stopper or plug), because it’s likely to get hung up somewhere and plug a blood vessel, causing a stoppage of the blood flow at that site. If that happens in a pulmonary (lung) artery, it’s a pulmonary embolism. You really want to avoid this, and flavonoids can be very helpful (you’ll see).

Sitting Can Be Dangerous to Your Health

But back to the plane. You’ve finally made it aboard, found your seat, shoehorned yourself in between two other sardines, and settled down for what you hope is an uneventful flight. You’re sitting there . . . sitting in very dry, low-pressure air with lower-than-normal oxygen levels* . . . sitting for hours with your knees bent . . . sitting while your ankles start to swell . . . but finally, you arrive. You get up, stretch, walk off the plane into the airport, and drop dead. So much for uneventful. Cause of death: sitting (OK, technically, pulmonary embolism due to sitting).


*Commercial airliners are pressurized to the equivalent of about 5000–8000 feet altitude, regardless of cruising altitude. This exacerbates the problem.


Well, that’s a worst-case scenario, and it’s rare, but it does happen. The problem with sitting for too long, in a cramped position that doesn’t allow you to move your legs very much (it’s called the “economy class syndrome”), is that your circulation gets sluggish. Specifically, the blood in the veins of your legs has an ever harder time flowing upward against the force of gravity, past the resistance point in your bent knees. It wants to return to your heart quickly and zip over to your lungs so it can ditch its load of carbon dioxide, get reoxygenated, return to your heart, and be pumped back out through your arteries again to nourish all the cells of your body.

So Don’t Just Sit There—Do Something!

But you’re not cooperating! You’re just sitting there, allowing your leg muscles to relax—the very muscles that normally (if they’re in good shape owing to regular exercise) keep your venous blood flowing briskly by gently compressing your veins through rhythmic, wavelike motions that you’re not even aware of. As your muscles relax, your veins (which are thin-walled, unlike your thick, muscular arteries) gradually stretch and dilate, and the blood flow slows down.

As more blood collects in your expanding veins, your venous blood pressure rises, owing to the weight of all that blood, which puts that much more strain on the vein walls. Down at the bottom of the circulation loop, your ankles start to swell, because the blood pressure in your capillaries has become so great that fluid is being forced through the walls into the surrounding tissues. That’s called ankle edema, and it affects almost all airline passengers to some degree, regardless of the state of their venous health.1

Worst of all, the blood in your veins may become so stagnant in places—a condition called stasis—that chemical reactions there lead to deep-vein thrombosis. The older you are, and the poorer your circulation was to begin with, the more likely this is to occur. The next step—usually within hours, if it does occur—could be a pulmonary embolism, which is a true crisis. It can cause severe respiratory problems, and although it probably won’t kill you, it could.

Do You Have Swollen Ankles?

These two conditions—deep-vein thrombosis and its evil spawn, pulmonary embolism—are often lumped together under the one term venous thromboembolism (VTE). Can VTE affect a normal, healthy person with good circulation? Yes, it can, but it’s much more likely to strike someone with significant risk factors (see the sidebar), of which the most important are weakened veins caused by a degenerative disease called chronic venous insufficiency (CVI).



What Is the Risk?

Worldwide, venous thromboembolism (VTE) is a common problem; it is estimated that over 250,000 cases occur annually in the United States alone. In children, the risk is zero, and in young adults, it’s minimal; it becomes appreciable only in the elderly, and the incidence increases steadily with advancing age, rising to about 1 in 100 in those over age 75. As our population becomes ever more geriatric, therefore, VTE will become an ever greater national health problem.1

Among the factors that increase one’s risk—aside from impaired circulatory function caused by a disease such as chronic venous insufficiency (CVI)—are being pregnant, old, obese, tall, or a smoker; taking hormones; having cancer; having previously had a thrombosis or embolism; and having recently had surgery. And, of course, flying—especially long-haul flights of more than about 5 or 6 hours, for which the risk is about 150 times higher than for relatively short flights. The possible association with flying was first suggested in 1954, and since then, many reports and studies have examined this question. Although the overall risk is judged to be small, the consequences of VTE canbe so grave (literally) that one must take the risk seriously.

Responding to published reports of severe illness and death from VTE, many companies have launched training programs to help their employees survive the unfriendly skies. The best advice is to move your legs as much as possible: stretch and wiggle them frequently, and get up and move about periodically. Drink plenty of fluids, but avoid alcohol and caffeine. Wear elastic compression stockings, which improve blood flow and have been found to cut the incidence of deep-vein thrombosis on long flights sharply.

Of course, the best strategy of all is to maintain optimal venous health at all times so as to minimize your risk. Having healthy veins when you get on the plane beats trying to prevent the possible consequences associated with poor venous health. Good diet, regular exercise, and potent vein-support supplements are the way to fly.

  1. Iqbal O, Eklof B, Tobu M, Fareed J. Air travel-associated venous thromboembolism. Med Princ Pract 2003;12:73-80.



The main cause of this disease is venous hypertension, or high blood pressure in the veins. And the primary cause of that is a weakening of the connective tissue that constitutes an integral part of the vein walls.* As the connective tissue gradually loses its strength, the veins lose their tone, and the blood pressure builds up. (Leg veins are the most vulnerable because gravity is their natural enemy—especially in tall individuals, whose blood has longer uphill distances to go.) The one-way flap valves inside the veins, designed to prevent the backflow of blood toward the feet, no longer close properly. This allows blood to flow back and become stagnant in places—the recipe for deep-vein thrombosis.


*The ultimate cause of all this is probably lack of exercise, because nothing beats exercise for maintaining good muscle tone and cardiovascular health. Regular exercise is the greatest preventive medicine known to man. And it’s free!


Under the relentless pressure, the capillaries of CVI patients become weakened and damaged too—a condition called microangiopathy—causing their extremely thin, fragile walls to become overly permeable. This allows excessive amounts of fluid to diffuse outward through the walls, particularly in the ankles, resulting in characteristic ankle edema—not just during long periods of sitting, but virtually all the time.

Aside from ankle edema, the other perceptible clues that one’s venous health may be seriously impaired are varicose veins, which appear on the surface of the legs, and hemorrhoids, which are just varicose veins in a more sensitive place. If you have either of these conditions, see your doctor. And by the way, ankle edema can also be a symptom of congestive heart failure or diabetes, so don’t try to self-diagnose if you have it—see your doctor.

Troxerutin Cuts Edema Dramatically

Probably the world’s most active researchers on the dangers of long-haul flights for people with chronic venous insufficiency—and, for that matter, for normal, healthy people—are a group of scientists in Italy and England whose collaboration has produced numerous studies on various aspects of this problem. Their work with the extraordinarily effective herb gotu kola (Centella asiatica)—particularly a high-potency extract from this herb called TTFCA—has been highlighted before in the pages of Life Enhancement.* Here we report on their recent work with a flavonoid called troxerutin,which is used in high-quality vein-support supplements, often with two other potent and widely prescribed flavonoids, diosmin and hesperidin.


*See “Gotu Kola Promotes Healthy Veins” (May 2002), “Gotu Kola Combats Venous Hypertension” (June 2002), and “Gotu Kola Can Help Prevent Heart Attack and Stroke” (August 2002).


The researchers used a commercial troxerutin product called Venoruton®, testing its effects vs. placebo in several randomized, controlled trials. Their primary focus was on “flight edema,” which afflicts almost all untreated passengers on flights of more than 7 hours, especially in economy class.

In one trial, they tested 139 men and women, average age 45, with mild cases of CVI (as evidenced by uncomplicated varicose veins) who took flights of 7–8 hours’ duration in economy class.2 The subjects received either placebo or 1 g of troxerutin twice daily for 3 days (2 days before the flight and the day of the flight). The researchers examined their ankles immediately before and after the flight to determine the amount of edema, and they recorded any accompanying symptoms, such as discomfort or pain.

The results were dramatic. In the control group, 89% of the subjects had a significant increase in ankle circumference (an obvious indicator of edema), with associated discomfort. In the troxerutin group, by contrast, edema occurred in only 12% of the subjects; furthermore, it was 2.3 times less severe and was not accompanied by significant discomfort. The troxerutin was well tolerated, with no side effects. No deep-vein thrombosis was observed in either group.

Troxerutin Also Protects Against Microangiopathy

The researchers obtained similar results in a trial involving 80 patients, average age 39, whose CVI was somewhat worse: varicose veins, edema, and initial skin alterations due to venous hypertension (in advanced cases of CVI, the end result of such skin alterations is ulcers).3 All the patients took flights of 9.0–9.5 hours’ duration (economy class), and the treatment protocol was the same as in the previous study. In this study, however, the researchers evaluated numerous factors related to venous function in addition to ankle edema.

On all measures, the troxerutin group fared significantly better than the control group. The researchers concluded that troxerutin had demonstrated a clear ability to provide effective control of edema and microangiopathy (the direct cause of the skin problems) in these patients.

Although these studies did not entail the occurrence of venous thromboembolism, the evidence they provided of troxerutin’s protective effects against some of the more common symptoms of venous disease gives reason to believe that the incidence of VTE would likely be reduced as well—a very good thing. Like several other natural supplements that have proved to be effective against venous disease, troxerutin thus appears to be a valuable aid in combating the health hazards of flying.

Exercise, Supplement, and Fly without Fear

Ordinarily, just sitting quietly and minding your own business is a great way to stay out of trouble. On an airplane, however, it could get you into a world of trouble, or even propel you suddenly into the next world. So don’t just sit around—exercise! And for an extra margin of safety, avail yourself of nutritional supplements that can help improve the quality of your life, and maybe even save it.

Note added in proof: Deep-vein thrombosis occurs not solely in the elderly, or in the legs. As we go to press, the 23-year-old pop musician Isaac Hanson is hospitalized for a venous blood clot in his arm.


  1. Landgraf H, Vanselow B, Schulte-Huerman D, Mulmann MV, Bergan L. Economy class syndrome: rheology fluid balance and lower leg oedema during a simulated 12-hour long-distance flight. Aviat Space Environ Med 1994;65:930.
  2. Cesarone MR, Belcaro G, Brandolini R, Di Renzo A, Bavera P, Dugall M, Simeone E, Acerbi G, Ippolito E, Winford M, Candiani C, Golden G, Ricci A, Stuard S. The LONFLIT4–Venoruton Study. A randomized trialprophylaxis of flight edema in venous patients. Angiology 2003;54:137-42.
  3. Cesarone MR, Belcaro G, Geroulakos G, Griffin M, Ricci A, Brandolini R, Pellegrini L, Dugall M, Ippolito E, Candiani C, Simeone E, Errichi BM, Di Renzo A. Flight microangiopathy on long-haul flights: prevention of edema and microcirculation alterations with Venoruton. Clin Appl Thrombosis/Hemostasis2003;9(2):109-14.