Featured Research

from universities, journals, and other organizations

When considering bariatric surgery, think about bones

Date:
November 2, 2012
Source:
Garvan Institute of Medical Research
Summary:
Bariatric surgery, which significantly curtails the amount of food a person can eat, is the most effective treatment against obesity and is being recognized as a potentially valuable tool in the fight against diabetes related to obesity. It is being performed on increasing numbers of people worldwide, including teenagers. Unfortunately, some types of bariatric surgery may also cause bone loss, a cause for concern, particularly when carried out on young people who have not yet reached their peak bone mass, say endocrinologists who have just published a new review.

Bariatric surgery, which significantly curtails the amount of food a person can eat, is the most effective treatment against obesity and is being recognized as a potentially valuable tool in the fight against diabetes related to obesity. It is being performed on increasing numbers of people worldwide, including teenagers.

Related Articles


Unfortunately, some types of bariatric surgery may also cause bone loss, a cause for concern, particularly when carried out on young people who have not yet reached their peak bone mass, say endocrinologists from Sydney's Garvan Institute of Medical Research, who have just published a review of current literature in the journal Obesity Reviews, now online.

Authors, Dr Malgorzata Brzozowska and Associate Professor Jackie Center, say that skeletal examination and treatment should be considered part of patient care, before and after procedures.

In the United States, 'Roux-en-Y' gastric bypass surgery, one of the most invasive of the procedures, is the most common. Much of the stomach is removed and part of the small bowel bypassed. Less radical is the 'gastric sleeve', which involves removing a large part of the stomach leaving a narrowed smaller stomach, restricting food intake and at the same time speeding the passage of food to the gut. The least invasive, and only reversible measure, is the 'gastric band', which is an inflatable ring placed between the esophagus and stomach, making it possible to eat only small amounts of food slowly.

"Even though we don't yet understand all the mechanisms, we can see that the more radical the procedure, the greater the bone loss long-term," said Dr Brzozowska, who undertook the review as part of her PhD.

Dr Brzozowska is the first person to do a widespread analysis of current research into the complex interrelationships between fat, bone and nutritional restriction.

"In many situations significant weight loss is associated with bone loss, with or without surgery. The more invasive types of surgery appear to heighten bone turnover and the associated bone loss. This is thought to be caused not only by rapid weight loss and absorption of fewer vital nutrients like vitamin D and calcium, but possibly also by changes in hormones released by fat and the gut, and their impact on the central nervous system," she said.

In particular, the review points out, we should be aware of surgery-induced changes in hormones that can affect the central regulation of appetite and bone strength. These include the fat-derived hormones leptin and adiponectin; gut-derived hormones such as peptide YY (PYY), glucagon-like peptide 1 (GLP-1) and ghrelin; and the hypothalamic regulator of energy balance, neuropeptide Y (NPY). However, although there is quite a lot of animal data concerning these hormones and their effects, human data are scanty.

Associate Professor Jackie Center believes that the findings are very important despite the widely held assumption that obese people are protected against bone fragility and fracture.

"It has always been assumed that the heavier someone is, the denser their bones will be, because bones become strong when they carry a load. While that is true up to a certain point, the bones may not continue to become stronger in the very obese, who can also have low bone density and fracture.

"Increasing evidence suggests that in very obese people, the relationship between bone density and weight fails and that the excess fat is detrimental to bone.

"While there are many studies looking at weight loss and improvement in insulin sensitivity after bariatric surgery, very few look at what happens in bone.

"We are certainly not arguing against bariatric surgery. There is no doubt that it is an effective weapon against obesity and obesity-related diabetes. We just ask that doctors and patients take bone health into account.

"Bone mineral densitometry scans can be done and adequate calcium and vitamin D intake advised. For those patients at particular risk, additional monitoring may be advised and protective drugs considered."


Story Source:

The above story is based on materials provided by Garvan Institute of Medical Research. Note: Materials may be edited for content and length.


Journal Reference:

  1. M. M. Brzozowska, A. Sainsbury, J. A. Eisman, P. A. Baldock, J. R. Center. Bariatric surgery, bone loss, obesity and possible mechanisms. Obesity Reviews, 2012; DOI: 10.1111/j.1467-789X.2012.01050.x

Cite This Page:

Garvan Institute of Medical Research. "When considering bariatric surgery, think about bones." ScienceDaily. ScienceDaily, 2 November 2012. <www.sciencedaily.com/releases/2012/11/121102115342.htm>.
Garvan Institute of Medical Research. (2012, November 2). When considering bariatric surgery, think about bones. ScienceDaily. Retrieved November 27, 2014 from www.sciencedaily.com/releases/2012/11/121102115342.htm
Garvan Institute of Medical Research. "When considering bariatric surgery, think about bones." ScienceDaily. www.sciencedaily.com/releases/2012/11/121102115342.htm (accessed November 27, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Thursday, November 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Leaves Orphans Alone in Sierra Leone

Ebola Leaves Orphans Alone in Sierra Leone

AFP (Nov. 27, 2014) — The Ebola epidemic sweeping Sierra Leone is having a profound effect on the country's children, many of whom have been left without any family members to support them. Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
Experimental Ebola Vaccine Shows Promise In Human Trial

Experimental Ebola Vaccine Shows Promise In Human Trial

Newsy (Nov. 27, 2014) — A recent test of a prototype Ebola vaccine generated an immune response to the disease in subjects. Video provided by Newsy
Powered by NewsLook.com
Pet Dogs to Be Used in Anti-Ageing Trial

Pet Dogs to Be Used in Anti-Ageing Trial

Reuters - Innovations Video Online (Nov. 26, 2014) — Researchers in the United States are preparing to discover whether a drug commonly used in human organ transplants can extend the lifespan and health quality of pet dogs. Video provided by Reuters
Powered by NewsLook.com
Today's Prostheses Are More Capable Than Ever

Today's Prostheses Are More Capable Than Ever

Newsy (Nov. 26, 2014) — Advances in prosthetics are making replacement body parts stronger and more lifelike than they’ve ever been. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins