Liwei Chen, MD, PhD, of the LSU Health Sciences Center, is the lead author on a paper demonstrating that weight gain and obesity are more linked to an increase in liquid calories than from solid food. The study - the first to document these effects - will be published in the May 1st issue of the American Journal of Clinical Nutrition.

The research team followed 810 men and women, 25-79 years of age, whose 24 hour dietary intake recall was measured by telephone interviews conducted when they entered the study, and again at 6 and 18 months into the program. The group reports four principal findings:

1: A reduction in liquid calorie intake was significantly associated with weight loss at both 6 months and 18 months.

2: The weight-loss effect of a reduction in liquid calorie intake was stronger than that of a reduction in solid calorie intake.

3: A reduction in sugar-sweetened beverage intake was significantly associated with weight loss at both 6 and 18 months.

4: No other beverage type was associated with weight change.

"Today, Americans consume 150-300 more calories a day than they did 30 years ago," notes Dr. Chen, "and caloric beverages account for approximately 50% of this increase."

The researchers offer a couple of possible explanations for their findings. The absence of chewing when consuming liquids may result in decreased pancreatic responses. Beverages also clear the stomach sooner than solid food and may induce weaker satiety signals in the gastrointestinal tract. "Our study supports policy recommendations and public health efforts to reduce the intake of liquid calories, particularly from sugar-sweetened beverages," concludes Dr. Chen.