Accelerated bone turnover remains after weight loss

Jul 28, 2008

When a person is losing a significant amount of weight, they expect to notice changes in their body. However, they may overlook changes happening in their bones. During weight loss through calorie-restricted diets, bones are being remodeled - breaking down old bone and forming new bone - at an accelerated rate. At the same time, bone density is decreasing, causing increased fragility.

In a new study, a University of Missouri researcher and collaborators at the University of Kansas found that the potentially harmful effects of weight loss on bone persist during weight maintenance following moderate weight loss.

Researchers examined protein markers of bone breakdown and formation in 37 obese, middle-aged adults who lost 20 percent of their body weight through a severe calorie-restricted diet. Protein markers, which are released during bone breakdown and formation, are used as indirect indicators of bone remodeling. During the 3-month weight-loss phase, bone remodeling was elevated, and bone formation and breakdown were imbalanced as a result of a low energy intake. After weight loss phase, bone remodeling remained elevated during the 9-month weight maintenance phase, but bone formation and breakdown appeared to be balanced.

"When people increased their calorie intake after weight loss, the bone remodeling markers did not respond and remained above what they were before weight loss," said Pam Hinton, associate professor of nutritional sciences in the MU College of Human Environmental Sciences. "However unlike the weight loss phase, it appeared that bone breakdown and bone formation were balanced. Rapid rates of bone remodeling, regardless of the balance of breakdown and formation, can increase bone fragility."

Hinton found that a greater reduction in body weight resulted in a greater increase in bone breakdown. Having a low-carbohydrate or a low-fat diet during the weight maintenance phase had no effect on bone remodeling in the participants. Hinton also found that gender, hormone replacement therapy and menopausal status did not affect changes in bone remodeling markers and body weight. Previous studies have reported elevated bone formation and breakdown and decreased bone mass after modest weight reduction in a 6 to 12 month period, Hinton said.

"From this study alone, it is impossible to determine the consequences of accelerated bone remodeling during weight maintenance," Hinton said. "Because bone strength adapts to match skeletal load, body weight is one of the strongest predictors of bone mass. People planning on losing a significant amount of weight should consider incorporating high-impact weight-bearing physical activity into their exercise routine and consuming adequate calcium to improve bone health."

Source: University of Missouri-Columbia

Explore further: The impact of bacteria in our guts

add to favorites email to friend print save as pdf

Related Stories

The battle against what spaceflight does to your health

May 30, 2014

Why do some astronauts come back from the International Space Station needing glasses? Eye problems are one of the largest problems that have cropped up in the last three to four years of space station science, ...

Life's first taste of phosphorus

Aug 23, 2012

Despite its impressive biological resume, phosphorus is relatively inaccessible as elements go. To understand how phosphorus obtained its prominent role, scientists are modeling the early geochemical environment ...

Tour de France Stresses Riders' Bodies to the Limit

Jul 19, 2010

Glancing at the elevation profiles of the stages of the 2010 Tour de France is enough to tire a couch potato. The mountainous race is legendarily strenuous, but beyond short-term discomforts such as road rash ...

Recommended for you

The impact of bacteria in our guts

10 hours ago

The word metabolism gets tossed around a lot, but it means much more than whether you can go back to the buffet for seconds without worrying about your waistline. In fact, metabolism is the set of biochemical ...

Stem cell therapies hold promise, but obstacles remain

10 hours ago

(Medical Xpress)—In an article appearing online today in the journal Science, a group of researchers, including University of Rochester neurologist Steve Goldman, M.D., Ph.D., review the potential and ch ...

New hope in fight against muscular dystrophy

11 hours ago

Research at Stockholm's KTH Royal Institute of Technology offers hope to those who suffer from Duchenne muscular dystrophy, an incurable, debilitating disease that cuts young lives short.

Biologists reprogram skin cells to mimic rare disease

Aug 21, 2014

Johns Hopkins stem cell biologists have found a way to reprogram a patient's skin cells into cells that mimic and display many biological features of a rare genetic disorder called familial dysautonomia. ...

User comments : 0