Is Obesity Promoted by Outdoor Fast Food Ads?

Past studies have suggested a relationship between neighborhood characteristics and obesity, as well as a connection between obesity and advertisements on television and in magazines.

Now, new research from UCLA has identified a possible link between outdoor food ads and a tendency to pack on pounds. The findings, researchers say, are not encouraging.

Researchers suggest that the more outdoor advertisements promoting fast food and soft drinks there are in a given census tract, the higher the likelihood that the area’s residents are overweight.

“Obesity is a significant health problem, so we need to know the factors that contribute to the overeating of processed food,” said Lesser, who conducted the research while a Robert Wood Johnson Foundation Clinical Scholar at the UCLA Department of Family Medicine and UCLA’s Fielding School of Public Health.

“Previous research has found that fast food ads are more prevalent in low-income, minority areas, and laboratory studies have shown that marketing gets people to eat more,” said Lesser, now a research physician at the Palo Alto Medical Foundation Research Institute in California. “This is one of the first studies to suggest an association between outdoor advertising and obesity.”

For the study, the researchers looked at two densely populated areas in Los Angeles and New Orleans, each with more than 2,000 people per square mile. They focused on more than 200 randomly selected census tracts from those two areas, which included a mixture of high- and low-income residents.

The team used data on outdoor food advertising in those areas gleaned from a previous study on ads and alcohol consumption (which had tracked all the outdoor ads). They then linked that information with telephone-survey data from the same study, in which nearly 2,600 people between the ages of 18 and 98 from those areas were asked health-related questions in addition to questions about their height, weight, self-reported body mass index (BMI) and soda consumption.

The researchers found a correlation: The higher the percentage of outdoor ads for food, the higher the odds of obesity in those areas.

“For instance, in a typical census tract with about 5,000 people, if 30 percent of the outdoor ads were devoted to food, we would expect to find an additional 100 to 150 people who are obese, compared with a census tract without any food ads,” Lesser said.

Given that the study focused on only two areas, the authors urge further research to determine if the findings would be replicated in other areas. Because the study was cross-sectional, the researchers do not claim that the ads caused the obesity. They also note that self-reported information about weight is subject to recall bias, and people often under-report their true weight.

But this study suggests enough of a link between outdoor food advertising and “a modest, but clinically meaningful, increased likelihood of obesity” to warrant further examination, the researchers conclude.

“If the … associations are confirmed by additional research, policy approaches may be important to reduce the amount of food advertising in urban areas,” the researchers write, while noting that outright bans on such ads might be deemed unconstitutional. “Innovative strategies, such as warning labels, counter-advertising, or a tax on obesogenic advertising should be tested as possible public health interventions for reducing the prevalence of obesity.”

Dietary Nutrients Associated With Sleep Patterns

Sleep, like nutrition and physical activity, is a critical determinant of health and well-being. With the increasing prevalence of obesity and its consequences, sleep researchers have begun to explore the factors that predispose individuals to weight gain and ultimately obesity. Now, a new study from the Perelman School of Medicine at the University of Pennsylvania shows for the first time that certain nutrients may play an underlying role in short and long sleep duration and that people who report eating a large variety of foods — an indicator of an overall healthy diet — had the healthiest sleep patterns.

“Although many of us inherently recognize that there is a relationship between what we eat and how we sleep, there have been very few scientific studies that have explored this connection, especially in a real-world situation,” said Michael A. Grandner, PhD, instructor in Psychiatry and member of the Center for Sleep and Circadian Neurobiology at Penn. ” In general, we know that those who report between 7 — 8 hours of sleep each night are most likely to experience better overall health and well being, so we simply asked the question “Are there differences in the diet of those who report shorter sleep, longer sleep, or standard sleep patterns?”

To answer this question, the research team analyzed data from the 2007-2008 National Health and Nutrition Examination Survey (NHANES) sponsored by the Centers for Disease Control and Prevention. NHANES includes demographic, socioeconomic, dietary, and health-related questions. The sample for the survey is selected to represent the U.S. population of all ages and demographics. For the current study, researchers used the survey question regarding how much sleep each participant reported getting each night to separate the sample into groups of different sleep patterns. Sleep patterns were broken out as “Very Short” (<5 h per night), ”Short” (5-6 h per night), ”Standard’ (7-8h per night), and ”Long” (9 h or more per night). NHANES participants also sat down with specially trained staff who went over, in great detail, a full day’s dietary intake. This included everything from the occasional glass of water to complete, detailed records of every part of each meal. With this data, the Penn research team analyzed whether each group differed from the 7-8 hour “standard” group on any nutrients and total caloric intake. They also looked at these associations after controlling for overall diet, demographics, socioeconomics, physical activity, obesity, and other factors that could have explained this relationship.

The authors found that total caloric intake varied across groups. Short sleepers consumed the most calories, followed by normal sleepers, followed by very short sleepers, followed by long sleepers. Food variety was highest in normal sleepers, and lowest in very short sleepers. Differences across groups were found for many types of nutrients, including proteins, carbohydrates, vitamins and minerals.

In a statistical analysis, the research team found that there were a number of dietary differences, but these were largely driven by a few key nutrients. They found that very short sleep was associated with less intake of tap water, lycopene (found in red- and orange-colored foods), and total carbohydrates, short sleep was associated with less vitamin C, tap water, selenium (found in nuts, meat and shellfish), and more lutein/zeaxanthin (found in green, leafy vegetables), and long sleep was associated with less intake of theobromine (found in chocolate and tea), dodecanoic acid (a saturated fat) choline (found in eggs and fatty meats), total carbohydrates, and more alcohol.

“Overall, people who sleep 7 — 8 hours each night differ in terms of their diet, compared to people who sleep less or more. We also found that short and long sleep are associated with lower food variety,” said Dr. Grandner. “What we still don’t know is if people altered their diets, would they be able to change their overall sleep pattern? This will be an important area to explore going forward as we know that short sleep duration is associated with weight gain and obesity, diabetes, and cardiovascular disease. Likewise, we know that people who sleep too long also experience negative health consequences. If we can pinpoint the ideal mix of nutrients and calories to promote healthy sleep, the healthcare community has the potential to make a major dent in obesity and other cardiometabolic risk factors.”