Cheaper Food May Be Fueling U.S. Obesity Epidemic

Latest Diet & Weight Management NewsIs Breakfast the Key to Weight Control?Health Tip: If You Aren't Hungry, Don't EatDiabetes Drug Spurs Weight Loss in NondiabeticsObesity Crisis Has Scaled Even the HimalayasObesity, Overweight Rates Jump Worldwide, ReportWant More News? Sign Up for MedicineNet Newsletters!

THURSDAY, May 22, 2014 (HealthDay News) -- Cheaper food could be a major cause of the obesity epidemic in the United States, according to a new study.

The study also found that it's an epidemic that is hitting all Americans, not just certain groups.

"Not only has food been getting cheaper, but it is easier to acquire and easier to prepare," Roland Sturm, lead author of the report and a senior economist at RAND, a nonprofit research organization, said in the group's news release.

"It's not just that we may be eating more high-calorie food, but we are eating more of all types of food," he said.

Sturm wrote the new data review along with Ruopeng An, of the University of Illinois at Urbana-Champaign. They wrote that "Americans are spending a smaller share of their income (or corresponding amount of effort) on food than any other society in history or anywhere else in the world, yet get more for it."

In the 1930s, Americans spent one-quarter of their disposable income on food. That fell to one-fifth in the 1950s, and currently is less than one-tenth of disposable income, the researchers noted.

Some common notions about the causes of obesity seem to be cast in doubt by the new research. They include theories such as Americans becoming fatter because they find fresh fruits and vegetables tougher to obtain; that exercise rates are falling; and that many Americans lack the time to exercise and eat better.

However, the RAND review found that rising obesity rates in the United States coincided with a rise in the availability of fruits and vegetables, as well as a rise in people exercising and having more leisure time.

So why are Americans still piling on excess pounds? The fact that Americans have the cheapest food available in history is likely the reason, the researchers said.

Many factors have been suggested as reasons for the steady climb in obesity rates over the past several decades, leading to the current situation where two in three Americans are overweight or obese. These factors include snack products and fast food, large portion sizes, vending machines, increased use of cars, and spending too much time in front of televisions and computers.

However, cheap food has the strongest link to obesity, according to the authors of the study published online May 22 in the journal CA: A Cancer Journal for Clinicians.

The RAND review also found that obesity is a growing threat to Americans everywhere, regardless of where they live or what social group they belong to.

The findings suggest that focusing on reducing calorie intake -- particularly from sugar-sweetened drinks and salty snacks -- might be a better way to reduce obesity rates than attempts to get Americans to eat more fruits and vegetables and get more exercise, according to the study authors.

-- Robert Preidt

Obesity Gene May Explain Why Some Gain Weight as They Age

By Dennis Thompson
HealthDay ReporterLatest Diet & Weight Management NewsIs Breakfast the Key to Weight Control?Health Tip: If You Aren't Hungry, Don't EatDiabetes Drug Spurs Weight Loss in NondiabeticsObesity Crisis Has Scaled Even the HimalayasObesity, Overweight Rates Jump Worldwide, ReportWant More News? Sign Up for MedicineNet Newsletters!

TUESDAY, May 27, 2014 (HealthDay News) -- A defective gene linked to obesity appears to affect impulse control and food choices. And this could explain why people with the gene have so much trouble maintaining a healthy weight as they age, a new U.S. study says.

Middle-aged and older people with obesity-associated variants of the FTO gene tend to gain weight, according to researchers from the National Institutes of Health. Moreover, scans detected reduced function in brain regions that govern impulsivity and perception of food texture and taste, the researchers found.

"Sure enough, people who carry one or two copies of the FTO variant show increased intake of high-calorie or fatty food as they age," said senior author Dr. Madhav Thambisetty, chief of clinical and translational neuroscience at the National Institute on Aging's Laboratory of Behavioral Neuroscience.

"There may be a common biological factor underlying both the risk for obesity during aging as well as obesity-related behavior like your ability to resist impulse eating," Thambisetty said.

Many studies have tied certain versions of the FTO gene to chronic obesity, but doctors have struggled to determine why the gene affects a person's risk of obesity, said Ruth Loos, director of the genetics of obesity and related metabolic traits program at the Icahn School of Medicine at Mount Sinai in New York City.

"These types of studies are important to disentangle the mechanism of why FTO is associated with obesity, but it's only one piece of a huge puzzle," Loos said.

In the United States, more than one-third of adults aged 65and over are obese, according to background information in the study.

About 45 percent of people in this study had at least one copy of the pro-obesity FTO variant, Thambisetty said, which tracks with the white population in the United States. About 16 percent of people had two copies of the gene, which confers an even greater risk of obesity.

The study focused on nearly 700 participants, including 69 people who agreed to annual PET scans to gather additional information regarding their brain structure and function. At the start of the study, average age was 46. All were participating in the Baltimore Longitudinal Study of Aging, one of the longest running studies of human aging in North America.

They first confirmed that body mass index increased in those with one or two copies of the FTO gene variant. They then compared brain PET scans of patients with the FTO variant with scans of non-carriers, looking for differences in brain function over time.

They found people with the gene variant had reduced function in their medial prefrontal cortex, a region thought to be important in controlling impulses and response to the taste and texture of food.

In a final step, the team reviewed data gathered on participants' personality and diet. The group at increased genetic risk for obesity showed a greater tendency to impulsivity as well as a greater intake of fatty foods during aging.

The effect appears to increase with the number of copies. "We see a dose effect, where these changes in impulsivity or a preference for fatty foods increase with multiple copies of the gene," Thambisetty said.

The findings are published May 27 in the journal Molecular Psychiatry.

If these results pan out in additional studies, they mean that people who have a greater genetic risk of obesity face an uphill battle to maintain a healthy weight.

"This should not be an excuse, but it has to be a partial explanation why intelligent and motivated individuals struggle so much, because they are fighting their biology and it's uncomfortable to fight your own biology," said Dr. Steven Lamm, medical director of the Tisch Center for Men's Health at NYU Langone Medical Center in New York City.

However, a genetic predisposition to obesity does not mean one is doomed to obesity.

"You may be genetically susceptible, but by living a healthy lifestyle you can overcome your genetics," Loos said. "You are not destined to be obese."

Thambisetty agreed, noting that previous studies have shown that people can overcome the obesity risk posed by the FTO gene through regular exercise.

Obesity, Overweight Rates Jump Worldwide, Report Finds

Latest Diet & Weight Management NewsIs Breakfast the Key to Weight Control?Health Tip: If You Aren't Hungry, Don't EatDiabetes Drug Spurs Weight Loss in NondiabeticsObesity Crisis Has Scaled Even the HimalayasObesity, Overweight Rates Jump Worldwide, ReportWant More News? Sign Up for MedicineNet Newsletters!

WEDNESDAY, May 28, 2014 (HealthDay News) -- In the past three decades, the number of overweight and obese people worldwide has jumped from 857 million to 2.1 billion, a new analysis shows.

Not only that, the United States is home to the highest proportion of the world's obese people, at 13 percent.

The study shows that obesity is a major public health epidemic in both developing and developed nations, said the researchers at the Institute for Health Metrics and Evaluation (IHME) at the University of Washington in Seattle.

They analyzed data collected between 1980 and 2013 about children and adults in 188 countries.

Rates of overweight and obesity rose from 29 percent to 37 percent among men and from 30 percent to 38 percent among women. Rates of overweight and obesity among men were higher in developed nations, while rates among women were higher in developing nations.

The researchers also found that peak obesity rates are occurring at younger ages in developed nations, according to the study that appears May 29 in The Lancet.

Rates of overweight and obese children worldwide rose by nearly 50 percent between 1980 and 2013. In 2013, more than 22 percent of girls and nearly 24 percent of boys in developed nations were overweight or obese. The rates in developing nations were nearly 13 percent for both boys and girls.

"The rise in obesity among children is especially troubling in so many low- and middle-income countries," study author Marie Ng, an assistant professor of global health at IHME, said in an institute news release.

"We know that there are severe downstream health effects from childhood obesity, including cardiovascular disease, diabetes and many cancers. We need to be thinking now about how to turn this trend around," she said.

The study also found that more than 50 percent of the world's 671 million obese people live in 10 countries: the United States, China, Russia, Brazil, Mexico, Egypt, Germany, Pakistan and Indonesia.

"Obesity is an issue affecting people of all ages and incomes, everywhere," IHME Director Dr. Christopher Murray said in the news release. "In the last three decades, not one country has achieved success in reducing obesity rates, and we expect obesity to rise steadily as incomes rise in low- and middle-income countries in particular, unless urgent steps are taken to address this public health crisis."

-- Robert Preidt

Obesity Crisis Has Scaled Even the Himalayas

Latest Diet & Weight Management NewsIs Breakfast the Key to Weight Control?Health Tip: If You Aren't Hungry, Don't EatDiabetes Drug Spurs Weight Loss in NondiabeticsObesity, Overweight Rates Jump Worldwide, ReportWant More News? Sign Up for MedicineNet Newsletters!

WEDNESDAY, May 28, 2014 (HealthDay News) -- Obesity rates in remote Himalayan mountain villages are five times higher than they were two decades ago, according to a new study that highlights the extent of the global obesity epidemic.

Obesity-related health issues have skyrocketed as well, the study found.

Researchers looked at data from more than 4,600 adults in the Gilgit Baltistan region of Pakistan who took part in surveys conducted in 1995 and 2013. Over those 18 years, the obesity rate rose from about 2 percent to almost 13 percent, and the proportion of overweight people increased from almost 12 percent to about 27 percent.

"Overweight and obesity is a rapidly growing public health burden in the rural population of Pakistan. Overall obesity and central obesity were significant correlates for type 2 diabetes and pre-diabetes in the high mountain study population," said Syed Shah, an associate professor at the Institute of Public Health of United Arab Emirates University, and colleagues.

The study was scheduled for presentation Tuesday at the European Congress on Obesity in Bulgaria. Findings presented at meetings are usually considered preliminary until published in a peer-reviewed medical journal.

Of the nearly 1,100 people who took part in the 2013 survey, more than 6 percent had type 2 diabetes and almost 8 percent had pre-diabetes. Those with a waist circumference of 35 inches or more were four times more likely to have diabetes than those with smaller waists. Obese people were 16 times more likely to have pre-diabetes than normal weight people.

However, the investigators also found that 9 percent of people were underweight, which shows that the region faces "a dual war" against both malnutrition and obesity, the researchers said in a European Congress news release.

-- Robert Preidt