(RxWiki News) Mom and dad are right when it comes to eating your veggies. They're good for your health and, combined with eating fewer calories, they can help you lose weight.
New research shows a diet rich with fruits and vegetables is linked with fat loss and improved weight, so adding them to your diet can be a useful strategy for losing extra pounds.
"For these reasons," researchers said in their report, "advice to increase vegetable and fruit consumption often accompanies guidelines for weight loss."
"Eat all your veggies!"
The study, led by Leah Whigham, PhD, research nutritionist with the US Department of Agriculture Agricultural Research Service at Grand Forks Human Nutrition Research Center in North Dakota, included 60 obese participants.
Participants were in their mid 30s on average, with a body mass index (BMI) over 33. They were randomly divided into one of two groups, with each group using a different weight loss program.
The diet for the first group involved eating 500 fewer calories per day, and the diet for the second group consisted of eating eight servings of vegetables and two to three servings of fruit each day.
Researchers excluded people who already regularly consumed more than five servings of fruits and vegetables each day, exercised 90 minutes or more each week, were pregnant or had drastic weight changes three months before the study.
They measured participants' height, weight and BMI, which takes the two into account.
They also measured the concentration of carotenoids, which are pigments from colorful fruits and vegetables, found in each of the participants after eating these foods.
Researchers took these measurements at the start of the study, three months later and after one year.
The amount of pigment in the participants shows more precisely how many colorful fruits and veggies were actually eaten, rather than relying only on what participants said they consumed.
Each group learned basic healthy eating facts from the Dietary Guidelines for Americans. They also engaged in exercise strategies twice a week for the first three months.
Additionally, they received two meals a day, five days a week on a regular schedule. During the fourth month, the groups received meals two days a week. Afterwards, they received regular phone calls for eight more months to check on their progress.
Researchers found the carotenoid concentrations increased during the first three months in all groups as the participants lost weight. These concentrations stayed high at the one year mark, and there was no difference between the two groups.
The fruits and veggies group ate a significantly higher amount of vegetables at three months compared to the other group, and it did not change after 12 months. As carotenoid concentrations increased, participants' overall weight, measurement of fat and percentage of fat went down.
"The correlation between increased serum carotenoids…and improved weight and fat loss add support to the advice to increase vegetable and fruit intake in an effort to reduce weight," the authors wrote in their report.
The calorie-restricted group lost about 11 pounds by the third month while the veggies group lost about a little more than 2 pounds on average.
Although the calorie-restricted group lost more weight overall than the fruits and veggies group, the authors say that increasing the veggies and fruit in the diet should go with the lower calorie intake.
"In fact, the individual who lost the most weight and fat during the study also increased serum carotenoids the most and was in the calorie reduction group," the authors said.
The study was published online October 1 in the journal Nutrition and Diabetes. The authors do not report any conflicts of interest.