Weight loss advice

You may spend all day hurried with work and activities, and in the evening prepare a great and relaxing dinner. But new research indicates that the longer you dine , the more weight you are likely to accumulate.

That's the moral of a week-long study involving 31 overweight and obese patients, especially women.

"We evaluated meal and sleep schedules in overweight / obese patients at the start of a trial to lose weight, before participants began the intervention," said lead author Dr. Adnin Zaman, endocrinologist at the Faculty of Medicine of the University of Colorado.

His team found that " eating later in the day was associated with a higher body mass index (BMI) and a greater amount of body fat ." BMI is a measure of body fat based on height and weight.

In the study, participants were enrolled in a weight-loss trial that compared daily calorie limits with eating at a restricted time. In other words, once the trial began, they could eat only during certain times of the day.

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90% of the participants were women. Their average age was 36 years.

One week before the start of the study, they were provided with electronic devices to monitor their activity and their sleep. They also asked them to take pictures with a cell phone of everything they ate . The time was included in the photos, with an application called MealLogger.

Zaman and his collaborators did not define which hours would be equivalent to "eating late", and did not record calories or nutritional values.

His team did notice that the participants who ate later in the day also went to bed later, although everyone slept, on average, seven hours a night.

Participants' meal consumption covered 11 hours a day, and typically the last meal was around 8 pm Those who ate later tended to have a higher BMI and body fat, the study found.

Although the majority of participants were women, Zaman said the findings could "also apply to men."

But, he added, the study was purely observational and more research is needed to understand why eating at a late hour could lead to obesity .

His team is already exploring whether eating at an earlier hour of the day, when people tend to be more active, could help prevent obesity.

"Future studies are also needed in which these methods are applied to people with normal BMI, and compared with an overweight / obese population ," Zaman said.

Lona Sandon is a program director at the Department of Clinical Nutrition at the Southwest Medical Center at the University of Texas, Dallas. He reviewed an advance of the findings, and it was not surprising.

Sandon has his own theories about why eating at a late hour of the day could lead to weight gain.

" When you eat a greater part of the calories from food at an earlier hour of the day, they may be more likely to be used for energy and less likely to be stored as fat due to different levels of hormones, " he said. You may also feel more satisfied with fewer calories.

"Eating at an hour later in the day, and more at night, seems to be linked to the accumulation of more body fat due to hormonal differences at that time of day," Sandon added.

What is your advice? Have breakfast and enjoy a substantial lunch.

"If you do not eat breakfast, have a light lunch and eat at an hour late at night because you have barely eaten all day, simply eating less at night will not work," Sandon warned. "Making lunch the biggest meal of the day, and having at least some breakfast , has worked for some of my clients so they can eat less at night or be satisfied with a lighter dinner."

The findings were presented Saturday at a meeting of the Endocrine Society in New Orleans. The investigations presented at meetings are considered preliminary until they are published in a journal reviewed by professionals.

More information

The Centers for Disease Control and Prevention of the United States. UU offers more information on healthy eating .

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