Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientific evidence for diets: don’t believe everything you read

23.02.2005


In a society increasingly fixated with body image, we are bombarded with so-called scientific evidence promoting the use of a myriad of diets. An article published today in the Open Access journal BMC Medical Research Methodology suggests that we shouldn’t take everything we read at face value, as most research articles reporting weight loss studies fail to indicate crucial patient characteristics that may bias the results.



Cheryl Gibson, from the University of Kansas School of Medicine, and colleagues found that over 90% of diet studies did not adequately and comprehensively describe their subjects, making them almost impossible to interpret accurately.

In the USA, 97 million adults are overweight or obese. Extensive studies on the role of diet, exercise and genes are being carried out in a general effort to better understand and prevent obesity.


The researchers analysed 231 articles reporting studies of the effects of diet restriction, diet restriction and exercise, or exercise only, on weight loss; as well as research studies on body composition, fat distribution, metabolism and aerobic fitness. The analysis included articles from 1966 to 2003 that reported studies of obese adult participants.

The team focused on how the articles reported subject characteristics, using the Consolidation of the Standard of Reporting Trials Characteristics (CONSORT) as a guide. The CONSORT statement is a list of 21 elements, recommended as essential for a study to be valid, by a panel of clinical investigators, epidemiologists, biostatisticians and journal editors. The characteristics the researchers chose to concentrate on were age, gender, general health, medication use (other than drugs taken to control obesity), ethnicity and postmenopausal status. It has been shown that all of these characteristics affect weight and can alter the effect of diet and exercise on weight loss.

The researchers also examined whether the sample size at the beginning and at the end of the study was indicated, by gender. “Without knowledge of the number of subjects who were lost to follow-up, readers are unable to judge the effectiveness of a clinical treatment or ascertain whether or not a research finding has practical significance” explain the authors.

Their results show that medication use was the least indicated of the characteristics, as 92% of the articles missed it out. The subject’s health status was ignored by 34% of the studies. Ethnicity was not indicated in 86% of the studies, and the subject’s age was not reported in 11% of the studies. 8% of the studies failed to report the postmenopausal status of their participants, and 4% did not indicate gender.

“We found major shortcomings in the reporting of subject characteristics” conclude the authors. “Many studies did not report variables that may explain some of the variance in outcomes […] and reveal poor adherence to published standards of reporting”.

Inadequate reporting can lead to biased results being accepted as valid. The quality of reporting for weight loss studies has to improve if we are ever to understand obesity.

Juliette Savin | alfa
Further information:
http://www.biomedcentral.com

More articles from Health and Medicine:

nachricht NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures
17.11.2017 | National Institute of Standards and Technology (NIST)

nachricht High speed video recording precisely measures blood cell velocity
15.11.2017 | ITMO University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>