Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

U of I study shows how to lose weight without losing bone

09.06.2008
A higher-protein diet that emphasizes lean meats and low-fat dairy foods as sources of protein and calcium can mean weight loss without bone loss--and the evidence is in bone scans taken throughout a new University of Illinois study.

The research, which compared the results of a high-protein, dairy-intensive diet with a conventional weight-loss diet based on the food-guide pyramid, was published in this month's Journal of Nutrition.

"This is an important finding because many people, especially women in mid-life, are concerned with both obesity and osteoporosis," said Ellen Evans, a U of I associate professor of kinesiology and community health and member of the U of I Division of Nutritional Sciences.

"Furthermore, treating obesity often increases risk for osteoporosis. Many people lose bone mass when they lose weight," she said.

Study co-author Donald Layman, a U of I professor of nutrition, has previously reported that protein-rich weight-loss diets preserve muscle mass, help lower blood sugar and lipids, and improve body composition by targeting weight carried in the abdomen.

In the recent study, Layman's diet prescribed approximately 30 percent of all calories from protein, with an emphasis on lean meats and low-fat dairy products.

The scientists recruited and randomized 130 middle-aged, overweight persons at two sites—the U of I and Pennsylvania State University. Participants then followed either the higher-protein weight-loss diet or a conventional higher-carbohydrate weight-loss diet based on the food-guide pyramid for four months of active weight loss followed by eight months of weight maintenance.

"Essentially we substituted lean meats and low-fat milk, cheese, yogurt, etc., for some of the high-carbohydrate foods in the food-pyramid diet. Participants also ate five servings of vegetables and two to three servings of fruit each day," Evans said.

Bone mineral content and density were measured with DXA scans of the whole body, lumbar spine, and hip at the beginning of the study, at four months, at eight months, and at the end of the 12-month period.

"In the higher-protein group, bone density remained fairly stable, but bone health declined over time in the group that followed the conventional higher-carbohydrate diet. A statistically significant treatment effect favored the higher-protein diet group," said Matthew Thorpe, a medical scholars (MD/PhD) student who works in Evans's lab and was the primary author of the study.

"The combination and/or interaction of dietary protein, calcium from dairy, and the additional vitamin D that fortifies dairy products appears to protect bone health during weight loss," he added.

Because higher-protein diets have been associated with elevated urinary calcium levels, some scientists have feared that these diets cause bone demineralization.

The U of I team measured these levels at the beginning and eight months into the study. Although the researchers did note increased amounts of urinary calcium in the higher-protein group, they attributed the source of the increased calcium to improved intestinal absorption of calcium rather than bone loss.

"Other recent studies using radiolabeled calcium have shown that the higher urinary calcium levels associated with higher-protein diets are not coming from bone as some researchers had believed," Thorpe said.

The U of I scientists will soon begin a similar study contrasting higher-protein, dairy-rich diets with conventional weight-loss diets in older, mildly frail women.

"We'll measure bone and muscle outcomes in the two groups after six months of weight loss. Ultimately we want to know if a higher-protein weight-loss diet that emphasizes lean meats, whey protein, and low-fat dairy consumption can reduce the risk for osteoporosis and muscle loss.

"We also want to learn how these changes in body composition will affect balance, gait, and other measures of physical function in this population known to be at high risk for osteoporosis and physical disability," she said.

Phyllis Picklesimer | EurekAlert!
Further information:
http://www.illinois.edu

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

NASA's Fermi catches gamma-ray flashes from tropical storms

25.04.2017 | Physics and Astronomy

Researchers invent process to make sustainable rubber, plastics

25.04.2017 | Materials Sciences

Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017

25.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>