The combination of these three habits is associated with a lower risk of obesity in children, according to a new study.

The study, which included 8,550 4-year-olds from around the United States, found that children who ate dinner with their families more than five times a week, slept for at least 10.5 hours a night, and watched less than two hours of TV a day were 40 percent less likely to be obese than children who did none of those things.

Roughly one in seven children who practiced all three of the behaviors was obese, compared with one in four youngsters who practiced none of them, according to the study, which was published in Pediatrics.

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Even maintaining just one of the routines–all of which, on their own, have been linked to a lower risk of childhood obesity in previous studies–lowered the odds that a child would be obese by about 25 percent, the study found.

“We found an independent effect of each, which suggests that doing more of them was better,” says lead study author Sarah Anderson, Ph.D., an assistant professor of epidemiology at Ohio State University. “If you were doing one, adding another one–either one–was associated with a lower prevalence of obesity.”

Many families in the study were already implementing at least some of the behaviors. Nearly 40 percent of the families practiced two of the three, which lowered the odds that a child was obese nearly as much as all three, the researchers found. However, just 15 percent of families practiced all three of the behaviors, according to the study.

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Households were more likely to practice all three if they were white, if they were two-parent families, if the mother wasn’t obese, if the mother had a bachelor’s degree, or if the household income was higher.

Significantly, however, the study found that the link between the behaviors and the lower risk of obesity held even after they controlled for a family’s economic status and other factors, which suggests that the behaviors are beneficial regardless of a family’s circumstances.

“We should encourage parents to have these routines for young children,” says Anderson. “In some families it’s going to be harder to do these things [because of] social and economic constraints, but we should consider what would make it possible for them to have these routines in their household.”

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William T. Dalton III, Ph.D., an assistant professor of psychology at East Tennessee State University, says that the relationship between the three routines in the study–as well as other factors that weren’t studied–is complex, and that they are likely interconnected.

“If kids are getting adequate sleep, they’re going to have more energy during the day to be physically active,” says Dalton, who has researched the link between families and obesity but was not involved in the current study. Similarly, he adds, children who eat dinner at the table with their family aren’t eating in front of the TV, a bad habit that often leads to less mindful eating and doesn’t teach children how to regulate their food intake.

The larger household context needs to be considered, says Dalton, not just certain behaviors in isolation. “I think it’s important to look at broader family functioning, in terms of how families work as a unit,” he says. “Are the families where kids don’t get enough sleep the types of families that have other challenges? [Maybe] both parents are working, so they let the kids stay up later because that’s their only chance to see them, and then staying up later leads to more snacking.”

Anderson acknowledges that the study, which used surveys to gauge the frequency of each routine in households, says little about how each household implemented the behaviors. “We don’t know who was eating dinner with the kids, what kind of TV was watched, or how well the child slept,” she says. Nor did she and her co-author assess what kind of food the children ate or how physically active they were.

Anderson and her co-author are unable to say with any certainty that eating dinner together more often, getting more sleep, and watching less TV will help any given child lose weight, because of the other factors that may contribute to a child’s obesity (or that may protect normal-weight children from becoming obese).

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Still, says Anderson, “We feel comfortable recommending these routines for the prevention of obesity. They may have a potential benefit for obesity, they also have a benefit for children’s development, and they’re not likely to cause the child any harm.” Although more research is needed to prove that these routines directly lower childhood obesity, she adds, parents shouldn’t wait to implement the behaviors in the study.

Nor, says Dalton, should the routines outlined in the study distract parents from the most important contributors to childhood obesity. In the end, he says, “It still comes down to eating too much and not being active enough.”

Desani Marshall was never really overweight, but she was always a little big for her age. During a checkup at age 4, her doctor pointed out to her mother that Desani was gaining weight more rapidly than he thought was normal. Six months later, she was still putting on pounds at a rapid pace—a strong predictor of future obesity.

“I didn’t take it seriously; I didn’t think it was that bad,” says Desani’s mother, Caryl Marshall, of New York City. “But then he showed me the growth chart. At the rate she was gaining, what really made me take it more seriously was what the future could be.”

Now 7, Desani is gaining weight at a normal pace, thanks in part to dietary changes—such as cutting out soda—that Marshall has implemented. “Everybody would look at her and say, ‘She’s so skinny. Why?’” Marshall says of her daughter’s regimen.

In some ways, Desani’s success story is an exception. Across the country, childhood obesity has only gotten worse. More than 20 years after it was first described as an epidemic, 17% of American children and adolescents are obese—triple the rate in 1980—and nearly one-third are overweight, according to the latest government data. Alarming statistics such as these have prompted government agencies, schools, and nonprofit organizations to launch a barrage of anti-obesity programs in recent years.

And no family—including the first family—is untouched by it, it seems. Michelle Obama recently started an anti-obesity campaign and also created a storm of controversy when she mentioned that at one point she was concerned about her own daughters’ risk of obesity. The family’s pediatrician told her to keep an eye on Sasha’s and Malia’s weight, so the family made some small changes to get the girls back on track, including less TV watching, smaller portions, and water in lunch boxes instead of other drinks. It made a difference, the first lady said, and the weight concern is a thing of the past.

But critics said she might be fostering eating disorders by discussing her daughters’ weight in public. Although eating disorders can be a risk in weight-conscious teens or preteens, research suggests that the more common scenario is that parents are oblivious to a child’s extra weight, and make no changes to reign in weight gain.

Parents clueless about kids’ weight
Parents tend to underestimate their child’s weight and the health risks associated with being too heavy, studies suggest. In a 2006 study that surveyed the parents of obese children, only one-half recognized that their child was overweight, and less than one-third said they were “worried” about their child’s weight. In another survey, only 38% of parents had taken steps, or were planning to take them, to help their obese child lose weight.

Several factors may be contributing to this indifference among parents, experts say. Some parents believe their child’s excess weight is just “baby fat,” for instance, and some may simply be in denial. Or it could be that parents have concluded their kid is normal after eyeballing his or her overweight peers.

“Because so many children are overweight and obese…they don’t stand out as much as they would have 20 or 30 years ago,” says nutritionist Elisa Zied, a registered dietitian and spokesperson for the American Dietetic Association. “I almost see a lack of concern with some parents.”

Parents should be concerned. Although some overweight kids do outgrow their baby fat, roughly two out of three are likely to grow up to be obese adults, according to a 2009 study by the U.S. Centers for Disease Control and Prevention (CDC). Childhood obesity, moreover, is associated with a slew of serious health problems, including diabetes, asthma, heart disease, and depression.

How do you know if your child’s chubbiness is baby fat or a serious health problem? You can’t always tell just by looking, and you can’t always count on pediatricians to broach the subject. But you can take matters into your own hands and adopt habits that will keep your child as healthy as possible.

You can’t trust your eyes
Most parents probably feel pretty confident that they know whether their child is overweight or not. The research tells a different story: A large proportion of the parents of overweight children—and especially mothers, who are surveyed more often—do not perceive their children as overweight. In some studies, the percentage of parents who don’t realize (or won’t admit) that their child is overweight has been reported to be as high as 80% to 90%.

It’s not entirely clear what accounts for this disconnect. For starters, many parents define obesity differently than health professionals do, and distrust the growth charts used by pediatricians. In a focus group discussion that was excerpted in the journal Pediatrics in 2001, one mother of a preschooler defined an obese person as someone who “can barely walk.” Other mothers denied that their children were fat or overweight, and instead used words like “big-boned,” “chunky,” and “solid” to describe them.

Susan Carnell, PhD, a research fellow and childhood obesity expert at the New York Obesity Research Center, attributes the failure of parents to accurately assess their child’s weight to changing social norms. Not only are kids heavier than ever before, but roughly two-thirds of adults are also overweight, and parents who are overweight themselves are less likely to identify their children as overweight, Carnell notes.

“We gain many of our perceptions from comparison with peers,” she says. “So if we compare a healthy-weight child with their overweight classmates, we may even think they are too skinny and try to feed them up.”

Social values and beliefs may also distort a parent’s perception. Parents are more likely to overestimate the weight of their daughters, for instance, perhaps because they feel it is less acceptable for girls to be heavy. Similarly, some studies suggest that parents of different ethnicities and cultural backgrounds have different conceptions of body type and overweight.

The doctor may not bring it up
If you’re waiting for your child’s pediatrician to tell you that your child is a bit heavy, don’t hold your breath. In spite of the myriad health risks associated with childhood obesity, pediatricians often fail to screen for it during annual checkups and office visits.

In a recently published survey of its members conducted by the American Academy of Pediatrics (AAP), virtually every pediatrician said they measured height and weight during checkups. But just 52% use those figures to calculate body mass index (BMI), a simple ratio of height-to-weight that provides a rough yet useful snapshot of whether a child is overweight for his or her age. (The CDC defines overweight as a BMI in the 85th percentile or above, and obesity as the 95th percentile or above.)

Even if they do feel that a child is overweight, many pediatricians are hesitant to say so, perhaps because they think it’s a touchy subject. In the AAP survey, only 59% of pediatricians said they believe that families want to discuss weight.

“I think some doctors are reluctant to bring up weight because they are not trained to deal with it sensitively,” says Carnell. Discussing a child’s weight with parents in the wrong way—by implying that they are to blame, for instance—can make parents “feel guilty and defensive,” she adds.

Doctors may also adopt a hands-off approach to weight because they feel there’s little they can do. Less than one-quarter of the pediatricians in the AAP survey believed that there are effective treatment strategies for overweight and obesity.

“We all have strategies we use that can make a difference with a certain proportion of kids,” says Eugene Dinkevich, MD, the division chief of general pediatrics at SUNY Downstate Medical School, in Brooklyn. “But it’s not like an ear infection where you can give someone an antibiotic and they’re better.”

Pediatricians only set aside about 15 minutes for a regular checkup, Dr. Dinkevich says, and they have to pick and choose which topics to discuss with parents in that time. Doctors must ask themselves, “What am I competent to talk about, and if I talk about it, will it make a difference?” he says. For far too many doctors, he adds, obesity treatment and prevention don’t fall into that category.

New guidelines for childhood obesity screening might help reassure pediatricians. In January, the U.S. Preventive Services Task Force, an independent panel of experts that advises the federal government on preventive care, released new guidelines that urge doctors to routinely calculate the BMI of children between the ages of 6 and 18. The guidelines also say that children who qualify as obese should be referred to various interventions, such as nutritional counseling or physical activity programs.

“In 2005, we said you can screen kids, but we had insufficient evidence of any effective therapy for weight loss,” says task force chairman Ned Calonge, MD, referring to the previous guidelines. “Now we have evidence that shows you can get modest weight loss through these intensive programs.”

What parents can do
Although the new guidelines may encourage pediatricians to monitor the weight of their patients more closely, parents should be proactive about doing so as well.

The easiest and best way to gauge whether your child is overweight or obese is to track their BMI using growth charts, which show the national percentiles for children by age. (Printable growth charts for boys and girls are available on the website of the CDC.)

Parents should monitor their children’s weight more or less from birth, experts say. “If they shoot up on the growth charts in terms of weight, that’s when you have to be aware of the situation,” says Zied. “You want to see consistency across the growth charts rather than any fluctuation.”

Periods of rapid weight gain have been shown to predict future obesity, says Samuel S. Gidding, MD, the chief of pediatric cardiology at the Nemours/Alfred I. duPont Hospital for Children.

Of course, prevention is also key. Parents need to choose good foods for their children as soon as they stop breast-feeding, says Dr. Gidding. “A lot of kids are being overfed, and they’re being fed foods that really have no business being in a child’s diet: sugar beverages, excess juice, lack of fruits and vegetables, too many french fries,” he says. “Parents really need to provide nutritious food while the child’s a baby.”

As children get older, parents should teach them about nutrition, appropriate portion sizes, healthy eating habits (such as sticking to regular meal times), and the importance of being active, according to Zied. These messages are often more successful if they’re delivered in kid-friendly terms, she adds. “Try to teach your kids what’s in it for them,” Zied says. “Are they going to run faster, throw the ball farther, get more baskets in? Teach it in terms that relate to them, because the health messages get lost.”

Above all, parents should remember that their kids are likely to adopt their eating and exercise habits, good or bad, and that they should therefore model healthy behavior.

“You have to practice what you preach,” says Zied. “If parents don’t have healthful habits, you can’t really expect kids to have those either.”

Obesity Counties

People who want to maintain a healthy weight over time shouldn’t obsess about their fat intake, new research shows.

The percentage of calories that a person got from fat, as opposed to protein or carbohydrates, had nothing to do with how much weight they gained in the coming years, the research team found.

The kinds of fat they ate didn’t matter either, Dr. Nita Forouhi of the Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge, UK and her colleagues found.

The findings, Forouhi noted in an email to Reuters Health, show that “it is more important to aim for a healthy lifestyle including a balanced healthy diet and regular physical activity, than to focus on fat intake alone as a factor for weight gain.”

The role of dietary fat content in obesity and weight gain is still controversial, Forouhi and her team note. To investigate, they looked at data on nearly 90,000 men and women from six different countries participating in the European Prospective Investigation into Cancer and Nutrition Study. Participants were followed for up to 10 years.

Average fat intake ranged from 31.5 percent to 36.5 percent of total calories. On average, people gained about a quarter of a pound every year. But analyses that accounted for several factors found no relationship between how much weight people gained and how much fat they ate, or their intake of polyunsaturated fats versus saturated fats.

The findings shouldn’t be seen as showing that people can eat as much fat as they want, Forouhi said. “That would be absurd, given so much evidence that already exists on the potential harms of diets high in saturated or trans-fats for heart health for instance,” the researcher said.

In the US, she added, dietary recommendations state that people should maintain a fat intake that is 20 percent to 35 percent of total calories, and eat “healthy” fats from fish, nuts, and vegetable oils instead of “unhealthy” saturated and trans fats.

She added: “The healthiest way to avoid weight gain is to make sure that, when appropriate, total calorie intake is limited by reducing one’s intake of added sugars, fats, and alcohol, which all provide calories but few or no essential nutrients, to watch portion sizes of food (so food portions consumed do not increase in size over time), and at the same time take regular physical activity.”