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Non-smokers may experience the effects of endothelial dysfunction

Dysfunction Junction

If someone smokes a pack of cigarettes a day, there’s no way around it, they’re going to suffer endothelial dysfunction (more on that in a moment).

Now you might say to that person, “Just look at your endothelium! It’s dysfunctional! You’ve got to quit this pack-a-day habit!”

But here’s the catch. What if that person isn’t a smoker? What if that person lives with a smoker or has a job that places him in a smoky environment? In that case, “quitting” becomes complicated. But endothelial damage steadily increases.

A non-smoker who spends several hours in a smoky environment takes about the same hit to the cardiovascular system as someone who smokes an entire pack of cigarettes. Studies have revealed this timeline of the way second hand smoke affects the heart:

  • Minutes: The aorta begins to stiffen
  • 30 minutes: The blood begins to become “sticky” with activated blood platelets; damage to the artery linings begins; blood vessel dilation is reduced
  • 2 hours: Heart rhythm may become disturbed
  • That part about “damage to artery linings” – that’s endothelial dysfunction (ED). And as you might guess, it puts your heart at considerable risk. But an intake of certain foods may be able to help smokers manage ED.

Of course, the best way for smokers to start addressing ED is to quit. So this one is for those passive smokers who have little or no say in the “quitting” issue.

It’s all about the NO

In a healthy person, the endothelial cells that line the heart and blood vessels release nitric oxide (NO). But when the endothelium is damaged, NO production is decreased and blood vessels become less responsive to changes in blood flow.

Studies have shown that foods containing flavanols may increase bioactive NO in the blood. (Flavanols are antioxidant and anti-inflammatory chemicals that give some fruits and vegetables their color.) Researchers at Heinrich-Heine University in Germany recently tested this NO reaction to flavanols in a cohort of 11 smokers.

Subjects were given a cocoa drink that contained 88 to 370 mg of flavanols or a flavanol-free drink that tasted the same. The next day, subjects crossed over in the drinks they received. On each day, two measures were recorded before the drinks: NO levels and blood vessel flow-mediated dilation. These measures were also taken two hours after the drinks.

Results showed that blood vessel response improved and NO levels increased significantly with the flavanol drink, but not the placebo.

Chocolate cigarette anyone?

Lead author for the Heinrich-Heine study, Christian Heiss, M.D., told NutraIngredients that it’s unlikely that cocoa can completely offset the harmful effects of smoking.

Unlikely? I’d say it would be VERY unlikely for cocoa to trump the damage that smoking does to the cardiovascular system. But then, Dr. Heiss may be trying to walk the line between serious research and deference to the company that supplied the cocoa drink: Mars. Yep: the candy company.

In the past few years we’ve seen a number of Mars-sponsored studies touting the health benefits of chocolate products. I wonder what Mars executives are up to? Sponsoring these relatively small studies seems like an odd and roundabout way to sell chocolate. Maybe they’re planning to launch a campaign to convince smokers to enjoy some “healthy” chocolate whenever they light up.

That would be an unlikely road to cardio health.

Nevertheless, the basic finding of this study – the confirmation that flavanol intake helps maintain the nitric oxide mechanism that promotes healthy arteries – provides those who are regularly exposed to secondhand smoke with a heart-healthy dietary tool. And sure, you can pick up some flavanols from cocoa products (especially dark chocolate), but far healthier sources of flavanols include apples, broccoli, onions, various berries, tea and wine.

Heart-health isn’t the only flavanol benefit. A 2003 study from Finland found that people who consumed large amounts of flavanol-rich foods were less likely to suffer from chronic diseases such as lung cancer, asthma, and type 2 diabetes.

“Acute Consumption of Flavanol-Rich Cocoa and the Reversal of Endothelial Dysfunction in Smokers” Journal of the American College of Cardiology, Vol. 46, 9/10/05,
“Flavanols May Improve Smokers’ Blood Vessel Health” NutraIngredients, 9/29/05,