Americans eat 2.8 billion pounds of chocolate a year, enticed by catchy slogans like "Do you dream in chocolate?"

And people are encouraged to indulge their sweet tooth by the numerous scientific reports that show chocolate is good for you — at least if it’s 70% dark chocolate in 1-ounce-a-day doses.

Unfortunately, that may make those who vape think chocolate-flavored electronic cigarettes are healthy too. Far from it.

A new study found that of all the lung-polluting elixirs added to e-cigs, chocolate flavor (with a high dose of what the researchers say is benzene-ring flavorings) is the most harmful.

According to the study, published in the American Journal of Physiology/Lung, Cellular, and Molecular Physiology, the chocolate flavor delivers a brew of toxins that can kill lung cells and reduce the ability of your immune system to remove bacteria and regulate inflammation.

Banana-, cherry-, and cinnamon-flavored vapes aren't much better for you.

Our advice: Your most healthy choice is to not smoke anything.

Back to chocolate: Three ounces of milk chocolate delivers 518 calories, 24 mg of cholesterol, 82 mg of sodium, and 54 grams of sugar. Three ounces of dark chocolate has 6 mg cholesterol, 19 mg sodium and around 39 mg sugar. That's better, but it still can have around 470 calories.

So while dark chocolate — with its anti-inflammatory powers — is a smart choice for a sweet treat, you want to eat it slowly and savor it in 1-ounce portions.