Millions of Americans will assume today that the quickest way to a lover's heart is through a luscious box of chocolates, even if it is not the healthiest of gifts.
But according to recent studies of chocolate's effects on cholesterol, at least in the medical sense these hopeful Valentines need not worry.
National food surveys clearly indicate that chocolate sets many a heart aflutter. But, the studies show, even a 3-pound heart-shaped box of the richest pure chocolate -- as sinful as its 6,900 calories may seem -- is unlikely to stop hearts dead in their tracks.
To be sure, chocolate is rich in saturated fatty acids. And, as nearly everyone knows, saturated fats are the villains when it comes to heart disease. These are the fats, solid at room temperature, that raise cholesterol levels in the blood and set the stage for heart attacks by clogging coronary arteries with cholesterol-laden deposits.
Yet highly saturated cocoa butter -- the very fat that gives chocolate its unique and universally appealing "mouth feel" -- almost miraculously spares blood vessels.
The essential component of cocoa butter is a saturated fatty acid known as stearic acid, found in larger amounts in chocolate than in any other food.
According to the studies presented last week at a "Chocolate in Perspective" symposium at the University of Texas Southwestern Medical Center in Dallas, underwritten by the Chocolate Manufacturers of America, stearic acid is like no other saturated fatty acid.
Dr. Margo Denke, a nutrition specialist at the university and organizer of the symposium, explained that before stearic acid has a chance to muck up the body's cholesterol metabolism, it is rapidly converted in the liver to oleic acid, a monounsaturate also present in olive and canola oils that neither raises nor lowers serum cholesterol.
Dr. Denke's colleague, Dr. Scott Grundy, an expert on how various fats affect the heart, concluded: "There's not much of a problem from eating two or three chocolate bars a week."
Dark chocolate is preferable, since milk chocolate by definition contains milk-derived butterfat in addition to its cocoa butter.
And it is always wise to read the label, since chocolate products like cocoa mixes and milk-chocolate coatings may contain other saturated fats like palm oil and coconut oil, which do raise cholesterol levels.
In studies in the journal Metabolism and presented at the symposium, Dr. Penny M. Kris-Etherton, a nutritionist at Pennsylvania State University in University Park, fed 33 healthy young men diets rich in different fats: cocoa butter, olive oil, soybean oil or dairy butter.
The diets provided a total of 37 percent of calories from fat, the average amount Americans now consume, with 81 percent of those fat calories coming from the particular fat being studied. After the subjects spent 26 days on the diets, scientists measured the men's cholesterol levels.
On the highly saturated cocoa butter diet, there was no increase in the men's serum cholesterol, just as there was none on the olive oil diet. But, as expected, the dairy butter diet, rich in saturated fatty acids called myristic and lauric, raised cholesterol levels.
And the soybean oil diet, rich in polyunsaturates, lowered them.
Dr. Kris-Etherton and her colleagues also examined the effects of milk chocolate. Again, she found no damaging effect on serum cholesterol.
Dr. Kris-Etherton suggested at the Dallas meeting that food companies could make more healthful products if they used cocoa butter in place of margarine or butter in certain products, replacing fatty acids with cholesterol-neutral stearic acid.