Life Extension Magazine

Life Extension Magazine February 2013

Report

Breakthrough in Protecting Arteries Against After-Meal Glucose Spikes

By Richard Mayer

Protecting arteries against after-Meal glucose Spikes  

Did you know that your risk of suffering from cardiovascular death is the greatest in the two-hour time period after you eat a meal? That’s partly because during that time, you can experience dangerous blood sugar spikes that acutely impair blood flow through vital arteries, ultimately leading to a heart attack or stroke.

And while you may not entirely eliminate these after-meal blood sugar surges, you can build up your body’s defenses against those spikes to protect your cardiovascular system.

In a study that may represent a breakthrough in the prevention of heart attack, the proper intake of gamma tocopherol was shown to limit the artery damaging impact of an after-meal glucose burst.

This human study, published in July 2012, showed an expected 30-44% decrease in endothelial function (as measured by arterial blood flow) in men after consuming 2.5 ounces of pure glucose. Men who took gamma tocopherol five days before the glucose challenge, however, showed no significant loss of endothelial function.1

This well-designed study showed how gamma tocopherol, functioning via several proven pathways, prepared the arterial endothelium to cope with the attack of after-meal glucose.

Foundation members have supplemented with gamma tocopherol since as early as 1996.This article describes the ways gamma tocopherol builds strong countermeasures into blood vessels, preparing them to survive and thrive even after a substantial spike in blood sugar.2

After-Meal Blood Sugar Spikes Increases Heart Attack Risk

When your heart muscle calls for more blood to sustain a strong pumping action, it needs it now. Under normal circumstances, the coronary arteries—those vessels that provide blood to the heart muscle—respond by dilating and increasing blood flow accordingly. When that response fails, heart muscle cells can begin to die within minutes.3

The after-meal blood sugar surge directly impairs your arteries’ ability to respond to that immediate demand for increased blood flow.4,5 That’s one of the reasons why diabetics have such a high rate of heart attacks and other cardiovascular disorders.6

But even if you don’t have diabetes, a “normal” fasting blood sugar measurement does not protect you against the harmful effects of the after-meal spike in blood glucose.4,5,7,8 Studies show that the risk of cardiovascular death increases in the two-hour time period after you eat a meal, when blood sugar exceeds just 90 mg/dL—a number well below the definition of diabetes.9

People who have normal fasting glucose but who fail a glucose tolerance test (blood sugar measured 2 hours after a test “meal” of glucose) are said to have “impaired glucose tolerance.” Their risk for cardiovascular disease raises sharply, the direct consequence of their arteries’ inability to dilate appropriately.3,9,10

In fact, many studies now show that the 2-hour glucose tolerance test is a more telling predictor of heart attacks than the much-touted fasting glucose test.11

How After-Meal Sugar Impacts Your Cardiovascular Risk

Lab Technician Working with Blood Samples  

Your risk for heart attacks, strokes, and other forms of cardiovascular disease rises dramatically when your after-meal glucose spikes.

One study showed that people who have elevated after-meal glucose levels have a 40% higher risk for cardiovascular disease in general, and a 56% greater risk for coronary artery disease, compared with normal levels.7

Another study found that men with the highest after-lunch blood sugar levels were more than twice as likely to have a “cardiovascular event” compared with those who had the lowest levels. In women that figure rose to an ominous 4.5-fold increase.11

In a study of non-diabetic people with metabolic syndrome, each increase in after-meal blood sugar of 18 mg/dL raised the risk of cardiovascular death by 26%.12

How does the after-meal burst of glucose cause such devastation?

Glucose has a powerful oxidizing effect on the arterial lining (the endothelium) that governs blood flow through the arteries.4,13 Oxidation products interfere with the production and bioavailability of nitric oxide, the signaling molecule that triggers arteries to dilate or constrict in response to changes in demand for blood flow.14-18

Worse, oxidation speeds the destruction of existing nitric oxide molecules, further impairing the endothelium’s ability to regulate blood flow in major arteries, including the coronaries.19

Together, these effects mean that a surge in blood sugar rapidly impairs your arteries’ ability to respond to your heart muscle’s immediate needs for more blood flow.14 To make matters worse, glucose surges raise levels of “adhesion molecules” that make both arteries and platelets “stickier,” increasing the risk of a fatal clot in a coronary artery.20

The stakes couldn’t be higher: Failure to protect your arteries from glucose spikes will starve your heart of blood flow, resulting, at best in an attack of angina, and at worst in a fatal heart attack.

You can’t completely avoid the spike in glucose that occurs after you eat. However, you can prepare your endothelial cells to cope with the after-meal surges in blood sugar with gamma tocopherol.

What You Need to Know
green olives plate

Fortify Your Arteries Against Damage Caused by Post-Meal Glucose Surges

  • The burst of glucose release that follows an hour or two after a meal is one of the most deadly risk factors for heart attacks.11,12
  • The oxidative effect of after-meal glucose spikes impairs your arteries’ ability to deliver blood flow to meet demand.4,5,14
  • That impairment is itself the result of reduced availability of nitric oxide, your body’s arterial signaling mechanism.14-18
  • Gamma tocopherol, a member of the vitamin E family, directly counteracts oxidant damage to nitric oxide signaling between endothelial (artery lining) cells and arterial muscles that control blood flow.14
  • Human studies now demonstrate that gamma tocopherol supplementation preserves endothelial function, allowing arteries to deliver their blood flow unimpaired, even following a glucose-rich meal.1,2 
  • Gamma tocopherol supplements are an essential part of your campaign to prepare your body before a meal for the inevitable blood sugar spike that follows it.1

Unique Property of Gamma Tocopherol

Alpha tocopherol is the form of vitamin E used most commonly in commercial supplements. However, studies indicate that it’s the gamma tocopherol form of vitamin E that is more ideally suited for protecting your heart from after-meal glucose surges.

Studies show that levels of gamma tocopherol are a better predictor of lower heart attack risk than alpha tocopherol. 21-25 Gamma tocopherol is a superior antioxidant that traps reactive oxygen species, reactive nitrogen species, and other dangerous molecules triggered by the after-meal glucose burst.21,22,26,27 If these dangerous molecules go unopposed, they attack fats in your artery linings, depressing nitric oxide levels and promoting atherosclerosis.28,29

Gamma tocopherol also provides anti-inflammatory effects that fights atherosclerosis induced by elevated after-meal glucose spikes.27,28,30-33 Gamma tocopherol is converted in your body to gamma-CEHC, a metabolite that helps shed excessive sodium; that’s a potential benefit for those whose mealtime sodium intake is higher than desirable.21,22,26

Finally, compared with alpha tocopherol, gamma tocopherol appears to be more readily absorbed into endothelial cells, where it can exert its antioxidant effects to protect endothelial health.34

Unfortunately, studies show that high intakes of alpha tocopherol suppress blood and tissue levels of the more important gamma tocopherol. This finding explains some of the apparently contradictory findings in studies done on vitamin E supplementation (see the SIDEBAR for other factors). 21,35,36

Gamma Tocopherol: Resolving a Scientific Paradox

Vitamin E has long posed a paradox to scientists.

Large epidemiological studies repeatedly show that a high intake of vitamin E-rich foods is protective against heart disease, but studies done on “vitamin E” supplementation have equally repeatedly failed to show a protective effect.32

Studies of gamma tocopherol suggest a resolution to that paradox.

Gamma tocopherol is the major form of vitamin E in natural foods; it has antioxidant, anti-inflammatory, and sodium-excreting properties.21,22,31 That explains the positive results in studies of natural vitamin E intake from food.

But alpha tocopherol is the vitamin E form used in virtually all previous supplementation studies. Its spectrum of effects is narrower and weaker than gamma tocopherol, explaining the failure of those studies to show benefit.26,32,38 Compounding the problem, alpha tocopherol lowers gamma tocopherol levels in blood and tissues, further reducing any potential benefit of alpha tocopherol supplementation.21,32,36

The supplementation studies were simply done with the wrong form of vitamin E!

With the vitamin E paradox resolved, we can expect to see even greater benefits from supplementation with gamma tocopherol, one of the more potent forms of the vitamin.32

Taken together, these factors led researchers at the University of Connecticut to explore the effects of gamma tocopherol on preventing the decline in endothelial function that accompanies the after-meal sugar spike. Let’s now examine their findings.

Gamma Tocopherol Protects against Blood Sugar Surges

In the year 2000, a study was published demonstrating that:

  1. After-meal blood sugar spikes in non-diabetic patients cause an immediate decline in endothelial function, and
  2. A combination of antioxidant vitamins could reverse that decline.8

This information remained dormant for more than a decade—until researchers in Connecticut and Korea rediscovered and amplified the findings.

These scientists had already discovered that an after-meal glucose surge raised the levels of methyl-glyoxal, a destructive byproduct of glucose metabolism that’s increased by oxidant stress.2

Suspecting that a powerful antioxidant such as gamma tocopherol could reduce the production of methyl-glyoxal following a glucose challenge, they supplemented 12 healthy young men with 500 mg/day of gamma tocopherol.2 As expected, methyl-glyoxal levels skyrocketed in the unsupplemented group following the glucose challenge.

Those supplemented with gamma tocopherol, on the other hand, had completely eliminated the rise of methyl-glyoxal, while markers of total antioxidant capacity rose substantially.

That study clearly proved that short-term gamma tocopherol supplementation could counteract one major oxidative effect of the glucose surge. Armed with this information, the researchers turned their focus to the next major consequence of the glucose surge, namely, impaired endothelial function. They designed a study that would reveal any changes in endothelial function and nitric oxide activity that might result from gamma tocopherol supplementation.1

The Breakthrough Gamma Tocopherol Study

In this study published in July 2012, fifteen young men underwent a baseline ultrasound test to detect how well their arteries would respond to blood flow changes. Blood tests were also performed.

The men then received a 5-day supplement with a mixture containing 500 mg of gamma tocopherol, 60 mg of alpha tocopherol, and small amounts of beta- and delta tocopherols. The ultrasound blood flow test and blood work were then repeated.1

Next the subjects received 2.5 ounces of pure glucose, and their endothelial function was monitored by ultrasound regularly for 3 hours.

The findings were remarkable.

Blood levels of gamma tocopherol rose 3-fold. Levels of the active metabolite, gamma-CEHC, rose 9-fold—all without affecting alpha tocopherol levels at all.1

Following the glucose “meal,” endothelial function, as measured by enlargement of blood vessels due to increases in blood flow, declined 30-44% in the unsupplemented state. But with supplementation, there was no significant loss of endothelial function.1

Supplementation with gamma tocopherol suppressed the after-meal increase in fat oxidation products and the nitric oxide disruption they caused.

In short, this well-designed study showed that supplementation with 500 mg/day of gamma tocopherol along with smaller amounts of other forms of vitamin E prepared arterial endothelium to cope with the attack of after-meal glucose. Supplementation didn’t change the fact of the surge; rather, it provided endothelial cells with the defense mechanisms they needed in order to survive it.

Most Life Extension members take around 200 mg a day of gamma tocopherol. Considering the many other similar nutrients they take like pomegranate and lycopene, they may not need to take any additional gamma tocopherol.  For those choosing to capitalize on the added benefits of gamma tocopherol supplementation, supplementing approximately12 hours before glucose consumption is advisable because studies show it takes 12 hours for maximal blood levels of the active metabolite gamma-CEHC to be reached.37

Summary

Taking a pill  

After you eat a meal—even a healthy meal—your arteries and their delicate endothelial linings are subject to a short but dangerous rise in blood sugar. That blood sugar surge directly impairs your ability to regulate blood flow, raising your risk for a heart attack or other cardiovascular disaster.14

You need to defend yourself against that after-meal blood sugar escalation, in order to protect your arteries and preserve their ability to deliver blood to your laboring heart muscle.

Gamma tocopherol has now been shown in a human study to block glucose-induced impairment of nitric oxide and to sustain endothelial function following a meal.1,2

Supplementation with gamma tocopherol, therefore, allows you to prepare your body for the harmful after effects of a meal.

Most Life Extension® members take over 200 mg a day of gamma tocopherol. Considering the many other similar nutrients they take like pomegranate and lycopene, they may not need to take any additional gamma tocopherol.

Since higher gamma tocopherol levels are associated with lower risk of coronary heart disease, gamma tocopherol supplementation may reduce your own risk, and restore your arteries’ natural abilities to manage the effects of deadly after-meal glucose surges.2

If you have any questions on the scientific content of this article, please call a 
Life Extension® Health Advisor at 1-866-864-3027.

References

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  2. 2. Masterjohn C, Mah E, Guo Y, Koo SI, Bruno RS. gamma-Tocopherol abolishes postprandial increases in plasma methylglyoxal following an oral dose of glucose in healthy, college-aged men. J Nutr Biochem. 2012 Mar;23(3):292-8.
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