While a spoonful of sugar might make the medicine go down, 21 spoonfuls will significantly lower your "good" cholesterol and spike your triglycerides, the fat associated with heart disease and stroke, according to a study published recently in the Journal of the American Medical Association.

Those 21 teaspoons constitute the average amount of added sugars consumed by Americans, according to the study. Make that 22 teaspoons, should you need an extra one for your heart medication.

Added sugar, such as corn syrup and other sweeteners added to everything from canned soup to, well, nuts, have long been associated with obesity, diabetes and dental cavities. This new study, led by researchers from Emory University in Atlanta, is the first to connect these sweeteners to blood lipids.

Addicted to sugars

The finding is particularly significant because the sugar trend is getting worse, with the average amount of added sugars now constituting 15.8 percent of the daily calories consumed by the average American, an increase from 10.6 percent in the 1970s, the researchers said.

Some of these sweeteners, such as high-fructose corn syrup, didn't exist a few generations ago. Now, it seems, most of the top killers — diabetes, obesity, cardiovascular disease and stroke — all are linked to sugar and its sweet cousins. These are additives (and risks) that could be avoided simply by ending our addiction to processed foods.

The researchers tapped into the National Health and Nutrition Examination Survey (NHANES) 1999-2006, a study combining interviews and physical examinations to assess the health and nutritional status of adults and children in the United States. Participants who were obese or diabetic were excluded from this most recent analysis in order to narrow in on the sugar-cholesterol connection.

The researchers found an inverse relationship between sugar consumption and good cholesterol, or HDL. Those participants consuming less than 5 percent of daily calories from added sugars had an average HDL level in the healthy range of 58.7 mg/dL; those consuming upwards of 25 percent of calories from added sugars averaged 47.7 mg/dL, on the borderline of heart attack risk. Similarly, researchers found a step-by-step rise in triglycerides with each added spoonful of sugars. Bad cholesterol, or LDL, increased too, only not as dramatically.

Sweet Surprise

The Corn Refiners Association, with its "Sweet Surprise" campaign, gleefully flaunts science studies revealing how high fructose corn syrup is not unhealthier than cane sugar. That doesn't make it safe, though. At issue is how such inexpensive sweeteners enable food manufacturers to sweeten food that doesn't need sweetening.

For example, homemade soup and bread recipes don't call for sugar, but you'd be hard pressed to find in a supermarket soup or bread or any processed food without some kind of sweetener. It all adds up and takes its toll on health.

The study also points to the complexity of the human body — how sugar and not, for example, eggs, which are high in cholesterol, can so negatively affect blood cholesterol levels.

Christopher Wanjek is the author of the books "Bad Medicine" and "Food At Work." His column, Bad Medicine, appears each Tuesday on LiveScience.