Study Ties Too Little Sleep With Too Much Weight

A study of 7-year-olds has found that sleeping less than nine hours a night was associated with being overweight or obese, even after accounting for amounts of television watching and physical exercise.

The study, being published Tuesday in the journal Sleep, also found that short sleep duration was associated with mood swings. The researchers had followed the subjects — 519 children in New Zealand — since birth, making periodic health and developmental assessments and interviewing their parents.

Sleep time did not affect I.Q. scores or measures of attention-deficit/hyperactivity disorder, but children who averaged less than nine hours’ sleep were significantly more likely than the others to be overweight.

Using sleep monitors, the scientists discovered some other patterns in the 7-year-olds. On average, the children stayed awake for 48 minutes after they went to bed, and slept about a half-hour longer on weekdays than weekends. They slept the least in the summer: 40 minutes longer on winter nights, 31 minutes longer in the fall and 15 minutes longer in the spring. Having a younger sibling cost a 7-year-old an average of 12 minutes of sleep per night.

“The study is important from the perspective of providing another means of preventing the development of obesity,” said Ed Mitchell, the senior author and a professor of child health research at the University of Auckland. “At least in New Zealand — and it needs to be confirmed in other age groups — this seems to be an important factor.”

By NICHOLAS BAKALAR

Conflict on the Menu

New York City’s new rules for menu labels at chain restaurants have set off a food fight among the nation’s obesity experts.

Most support the theory of the city’s health commissioner that forcing chain restaurants to list the calories alongside menu items — flagging that a Double Whopper With Cheese has 990 calories, for example — will make patrons think twice about ordering one. The rules are set to take effect at the end of March.

There is a countertheory, however, set forth by Dr. David B. Allison, the incoming president of the Obesity Society, a leading organization of obesity doctors and scientists. An affidavit he recently submitted to the United States District Court for the Southern District of New York has ignited a controversy within his organization.

In the filing, Dr. Allison argues that the new rules could backfire — whether by adding to the forbidden-fruit allure of high-calorie foods or by sending patrons away hungry enough that they will later gorge themselves even more.

“What harms (if any) might result” from the new rules? Dr. Allison wrote in the court filing. “That is difficult to predict.”

It might be only a scientific debate among nutrition experts, except for the fact that Dr. Allison was paid to write the document on behalf of the New York State Restaurant Association, which is suing to block the new rules.

Dr. Allison’s role in the debate has angered some members of the Obesity Society, setting off an e-mail fury since word of his court filing began to circulate. Some have pointed to Dr. Allison’s other industry ties, which have included advisory roles for Coca-Cola, Kraft Foods and Frito-Lay.

Many of the group’s 1,800 members are “completely mad that a president-elect of the Obesity Society, an organization that cares about obesity and cares about healthy eating, wants to hold back information from people that helps them make healthy choices,” said Dr. Barry M. Popkin, a member of the organization, who is director of the Interdisciplinary Obesity Center at the University of North Carolina, Chapel Hill.

Dr. Popkin has filed his own affidavit in the lawsuit, defending the city’s menu labeling plan.

The controversy highlights unresolved issues in the obesity field about industry ties and conflicts of interest, said Dr. Kelly D. Brownell, director of the Rudd Center for Food Policy and Obesity at Yale University. “The field is incapable of policing itself,” Dr. Brownell said.

Spurred by Dr. Allison’s affidavit, the obesity group released a statement on Tuesday supporting calorie labeling on menus. “The Obesity Society believes that more information on the caloric content of restaurant servings, not less, is in the interests of consumers,” said the statement by the society, which is based in Silver Spring, Md.

Dr. Allison, a professor of biostatistics and nutrition at the University of Alabama, Birmingham, is scheduled to start a one-year term as president of the Obesity Society in October. He has defended his affidavit. In a telephone interview, he said he did not take a position for or against menu labeling in the document but merely presented the scientific evidence that the labeling might deter over-eating but might not and, in fact, might be harmful.

He also defended his work for the restaurant industry, but would not disclose how much he was paid for his efforts.

“I’m happy to be involved in the pursuit for truth,” Dr. Allison said. “Sometimes, when I’m involved in the pursuit for truth, I’m hired by the Federal Trade Commission. Sometimes I help them. Sometimes I help a group like the restaurant industry. I’m honored that people think my opinion is sufficiently valued and expert.”

The executive vice president for the restaurant association’s metropolitan New York chapters, E. Charles Hunt, said that Dr. Allison was retained by the association’s lawyers. “Obviously, a lot of it was in favor of our position,” Mr. Hunt said, “although he didn’t come right out and say that.”

Dr. Allison’s 33-page affidavit cites a study that found that dieters who were distracted while eating and presented with information that food was high in calories were more likely to overeat.

“To the extent that many NY diners consume food from restaurants while in a state of distraction or performing distracting tasks,” he writes, “we might hypothesize that the belief that the food is especially high in calories would trigger disinhibited increased consumption.”

He also says that for some people, the deterrent of a high-calorie label might be short-lived and end up making them even hungrier and likely to eat even more later — “inadvertently encouraging patrons to consume lower-calorie foods that subsequently lead to greater total caloric intake because of poor satiating efficiency of the smaller calorie loads.”

Dr. Allison was quoted advancing similar arguments in 2006 during a breakfast meeting sponsored by Coca-Cola at an international conference of obesity experts in Sydney.

Dr. Allison, who disclosed at the meeting that he was a consultant to Coca-Cola on obesity issues, warned that policies to restrict certain foods might backfire, citing research showing that birds put on weight when food is scarce, according to a newsletter article about the conference.

The new labeling rules by New York City’s Board of Health have support from a cross section of organizations, including consumer groups like Public Citizen and the Center for Science in the Public Interest, as well as doctor groups like the American Medical Association, the American Academy of Pediatrics, the American Diabetes Association and the American Heart Association.

While some chains already post calorie information on posters, fliers or on the Internet, public health officials argue that people may change their ordering habits or restaurants might change their menus if calorie labeling is more conspicuous.

The New York rule would require that chains with 15 or more restaurants nationally, including fast-food restaurants, put the information on their menus or menu boards.

This is the city’s second attempt to adopt such regulations. A judge struck down a menu-labeling plan last year, saying the law needed to be reworded. It has since been revised to comply with the judge’s order.

Similar requirements have been adopted in King County, Wash., which includes Seattle, and are under consideration by 21 other state and local governments.

New York’s health commissioner, Dr. Thomas R. Frieden, likened Dr. Allison’s claims to an argument that the world is flat.

“We don’t have 100 percent proof that it’s going to work, but we have a reasonable expectation it will be successful,” Dr. Frieden said.

“When places have to put ‘2,700 calories’ next to an appetizer,” Dr. Frieden said, “they might not have a 2,700-calorie appetizer anymore.”

By STEPHANIE SAUL

For the Overweight, Bad Advice by the Spoonful

Americans have been getting fatter for years, and with the increase in waistlines has come a surplus of conventional wisdom. If we could just return to traditional diets, if we just walk for 20 minutes a day, exercise gurus and government officials maintain, America’s excess pounds would slowly but surely melt away.

A month-long series of discussions with reporters and experts on weight loss, fitness, children's health, emotional well-being and nutrition.
Gina Kolata on Fitness

This week Times reporter Gina Kolata hosts a discussion on exercise and losing weight. Ask questions and share your thoughts with other readers.

Scientists are less sanguine. Many of the so-called facts about obesity, they say, amount to speculation or oversimplification of the medical evidence. Diet and exercise do matter, they now know, but these environmental influences alone do not determine an individual’s weight. Body composition also is dictated by DNA and monitored by the brain. Bypassing these physical systems is not just a matter of willpower.

More than 66 percent of Americans are overweight or obese, according to the federal Centers for Disease Control and Prevention, in Atlanta. Although the number of obese women in the United States appears to be holding steady at 33 percent, for most Americans the risk is growing. The nation’s poor diet has long been the scapegoat. There have been proposals to put warning labels on sodas like those on cigarettes. There are calls to ban junk foods from schools. New York and other cities now require restaurants to disclose calorie information on their menus.

But the notion that Americans ever ate well is suspect. In 1966, when Americans were still comparatively thin, more than two billion hamburgers already had been sold in McDonald’s restaurants, noted Dr. Barry Glassner, a sociology professor at the University of Southern California. The recent rise in obesity may have more to do with our increasingly sedentary lifestyles than with the quality of our diets.

“The meals we romanticize in the past somehow leave out the reality of what people were eating,” he said. “The average meal had whole milk and ended with pie.... The typical meal had plenty of fat and calories.”

“Nostalgia is going to get us nowhere,” he added.

Neither will wishful misconceptions about the efficacy of exercise. First, the federal government told Americans to exercise for half an hour a day. Then, dietary guidelines issued in 2005 changed the advice, recommending 60 to 90 minutes of moderate exercise a day. There was an uproar; many said the goal was unrealistic for Americans. But for many scientists, the more pertinent question was whether such an exercise program would really help people lose weight.

The leisurely after-dinner walk may be pleasant, and it may be better than another night parked in front of the television. But modest exercise of this sort may not do much to reduce weight, evidence suggests.

“People don’t know that a 20-minute walk burns about 100 calories,” said Dr. Madelyn Fernstrom, director of the weight-management center at the University of Pittsburgh Medical Center. “People always overestimate the calories consumed in exercise, and underestimate the calories in food they are eating.”

Tweaking the balance is far more difficult than most people imagine, said Dr. Jeffrey Friedman, an obesity researcher at Rockefeller University. The math ought to work this way: There are 3,500 calories in a pound. If you subtract 100 calories per day by walking for 20 minutes, you ought to lose a pound every 35 days. Right?

Wrong. First, it’s difficult for an individual to hold calorie intake to a precise amount from day to day. Meals at home and in restaurants vary in size and composition; the nutrition labels on purchased foods — the best guide to calorie content — are at best rough estimates. Calorie counting is therefore an imprecise art.

Second, scientists recently have come to understand that the brain exerts astonishing control over body composition and how much individuals eat. “There are physiological mechanisms that keep us from losing weight,” said Dr. Matthew W. Gilman, the director of the obesity prevention program at Harvard Medical School/Pilgrim Health Care.

Scientists now believe that each individual has a genetically determined weight range spanning perhaps 30 pounds. Those who force their weight below nature’s preassigned levels become hungrier and eat more; several studies also show that their metabolisms slow in a variety of ways as the body tries to conserve energy and regain weight. People trying to exceed their weight range face the opposite situation: eating becomes unappealing, and their metabolisms shift into high gear.

The body’s determination to maintain its composition is why a person can skip a meal, or even fast for short periods, without losing weight. It’s also why burning an extra 100 calories a day will not alter the verdict on the bathroom scales. Struggling against the brain’s innate calorie counters, even strong-willed dieters make up for calories lost on one day with a few extra bites on the next. And they never realize it. “The system operates with 99.6 percent precision,” Dr. Friedman said.

The temptations of our environment — the sedentary living, the ready supply of rich food — may not be entirely to blame for rising obesity rates. In fact, new research suggests that the environment that most strongly influences body composition may be the very first one anybody experiences: the womb.

According to several animal studies, conditions during pregnancy, including the mother’s diet, may determine how fat the offspring are as adults. Human studies have shown that women who eat little in pregnancy, surprisingly, more often have children who grow into fat adults. More than a dozen studies have found that children are more likely to be fat if their mothers smoke during pregnancy.

The research is just beginning, true, but already it has upended some hoary myths about dieting. The body establishes its optimal weight early on, perhaps even before birth, and defends it vigorously through adulthood. As a result, weight control is difficult for most of us. And obesity, the terrible new epidemic of the developed world, is almost impossible to cure.

Published on August 30, 2007.