Kimber Stanhope of the University of California, Davis, says the American Heart Association recommends that people consume only 5 percent of calories as added sugar. The Dietary Guidelines for Americans 2010 suggest an upper limit of 25 percent or less of daily calories consumed as added sugar.
In this study, researchers examined 48 adults ages 18-40 and compared the effects of consuming 25 percent of one's daily calorie requirement as glucose, fructose or high fructose corn syrup on risk factors for cardiovascular disease. Study participants consumed high fructose corn syrup as 25 percent of their daily calories.
The study, published in the Journal of Clinical Endocrinology & Metabolism, found that within two weeks, study participants consuming fructose or high-fructose corn syrup, but not glucose, exhibited increased concentrations of low-density lipoprotein, "bad" cholesterol, as well as triglycerides and apolipoprotein-B -- a protein that can lead to plaques that cause vascular disease.
"Our findings demonstrate that several factors associated with an elevated risk for cardiovascular disease were increased in individuals consuming 25 percent of their calories as fructose or high fructose corn syrup, but consumption of glucose did not have this effect," Stanhope says in a statement.