Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Old age offers no protection from obesity's death grip

06.02.2013
Getting older increases Americans' risk of death from excessive BMI, finds new study, correcting flaw in earlier 'obesity paradox' research

Obesity kills, giving rise to a host of fatal diseases. This much is well known. But when it comes to seniors, a slew of prominent research has reported an "obesity paradox" that says, at age 65 and older, having an elevated BMI won't shorten your lifespan, and may even extend it.

A new study takes another look at the numbers, finding the earlier research flawed. The paradox was a mirage: As obese Americans grow older, in fact, their risk of death climbs.

Ryan Masters, PhD, and Bruce Link, PhD, at Columbia University's Mailman School of Public Health, in collaboration with Daniel Powers, PhD, at the University of Texas published the results online in the American Journal of Epidemiology.

The researchers argue that past studies of longevity and obesity were biased due to limitations of the National Health Interview Survey, or NHIS, which provides information on obesity. The survey excludes individuals who are institutionalized, such as in a hospital or nursing home—a group largely made up of seniors. Consequently, the data is overrepresented by older respondents who are healthy, including the relatively healthy obese. What's more, many obese individuals fail to make it to age 65—and thus do not live long enough to participate in studies of older populations.

"Obesity wreaks so much havoc on one's long-term survival capacity that obese adults either don't live long enough to be included in the survey or they are institutionalized and therefore also excluded. In that sense, the survey data doesn't capture the population we're most interested in," says Dr. Masters, a Robert Wood Johnson Foundation Health & Society Scholar at Columbia's Mailman School and the study's first author.

In his analysis Dr. Masters matched NHIS data on obesity with corresponding records in the National Death Index using data from close to 800,000 adults surveyed between 1986 and 2004. Next he performed statistical adjustments to account for the survey selection biases. The result: risk for death from obesity increases with age.

The finding jibes with countless medical studies that document how obesity takes a cumulative, even compounding toll on the human body. (Exponents of the obesity paradox have explained their counterintuitive results by suggesting that obesity's extra padding protects seniors from fall-related injuries and provides energy reserves during illness.)

"This study should put to rest the notion that it's possible to 'age out' of obesity risk, and provides a powerful counterfactual against those who say concern over obesity is overhyped," says Dr. Link, a professor of Epidemiology and Sociomedical Sciences at the Mailman School.

Going forward, Dr. Masters has set his sites on another possible reason behind the obesity paradox—that some of the older obese captured in NHIS data only put on extra weight later in life.

"The recent obesity epidemic hit all age groups at the same time, meaning many of the elderly obese only gained their excess weight in the last 10 years or so," Dr. Masters says. "To account for this fact, I will take a page from studies of cigarette smokers by looking at 'life years' to measure how long someone has been obese rather than whether or not they happen to be obese at the time of a single snapshot survey."

Funding was provided by the Robert Wood Johnson Foundation Health & Society Scholars Program. The authors declare no conflicts of interest.

Timothy S. Paul | EurekAlert!
Further information:
http://www.columbia.edu

More articles from Studies and Analyses:

nachricht Researchers simplify tiny structures' construction drip by drip
12.11.2018 | Princeton University, Engineering School

nachricht Mandibular movement monitoring may help improve oral sleep apnea devices
06.11.2018 | Elsevier

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>