NEW YORK Don't look now, but invisible cauliflower may be lurking in your chicken casserole -- and helping you lose weight.
Adding hidden pureed vegetables to entrees can reduce the number of calories the meals pack without sacrificing texture or taste, helping to cut the overall calorie intake, a study at Pennsylvania State University found.
Using "stealth vegetables" to pad dishes in the study of unsuspecting adults had an additional benefit, researchers found -- the participants more than doubled their intake of fiber and vitamin-packed veggies without even knowing it.
"The overconsumption of energy-dense foods leads to excessive energy intakes," wrote Alexandria Blatt in the American Journal of Clinical Nutrition.
"The substitution of low-energy-dense vegetables for foods higher in energy density can help decrease energy intakes but may be difficult to implement if individuals dislike the taste of vegetables."
The study included 20 men and 21 women who agreed to eat at a laboratory once a week for three weeks.
Volunteers were served as much as they wanted to eat, along with side dishes such as bread rolls, strawberry yogurt, broccoli and green beans, depending on the meal, and given snacks such as carrot sticks or fig cookies to take home.
The meals were always the same: carrot bread for breakfast, macaroni and cheese for lunch and chicken-and-rice casserole for dinner. Portion sizes were controlled by weight and the researchers kept a close account of the amount of food eaten.
Unknown to the diners, back in the kitchen cooks were slipping in vegetables that had been steamed and then pureed -- cauliflower, squash or carrots, depending on the entree -- to some of the main dishes. The result was a helping of food that was either 15 percent or 25 percent vegetable by weight, although it looked, tasted and otherwise resembled the original.
Some participants got the traditional version of the entree.
The study subjects all ate about the same amount of a given entree regardless of how much puree, if any, it contained. But those who were eating the altered foods saw their calorie intake drop substantially -- as much as 360 calories a day -- at the same time their vegetable intake rose.
Cutting 360 calories a day means a person could lose about half a kilogram (one pound) in about 10 days.
Nearly half the subjects said at the end of the study that they could tell something was different about the altered meals, but only two said they could taste the extra vegetables.
Blatt said that this strategy could led to substantial reductions in energy intake and an increase in vegetable consumption, but others were skeptical, noting that eating more veggies and fruits is "not a panacea" for weight loss.
Richard Mattes, a professor of foods and nutrition at Purdue University in Indiana who wasn't involved in the study, added that other studies had shown the big problem was getting people to stick to a new meal plan even if it was effective.
"Many people said they were not going to spend the extra money on fresh fruits and vegetables, or shop more often, or spend more time preparing them," he said.
Noting that U.S. citizens don't seem eager to embrace healthy diets, he added: "It's interesting that we have to go to such extents to get people to consume more vegetables."
(Reporting by Adam Marcus at Reuters Health; editing by Elaine Lies)