A joint study has found through applied carbon dating to DNA that the number of fat cells stay constant in adulthood no matter how thin or fat the individual is or how much weight they put on or loose.
The study was carried out between Lawrence Livermore National Laboratory scientist Bruce Buchholz – along with colleagues from the Karolinska Institute in Sweden; Humboldt University Berlin, Foundation of Research and Technology in Greece; Karolinska University Hospital; and Stockholm University
This study indicates that the number of fat cells is set during childhood and adolescence.
Previous studies had determined that fat cell volume increases but no one had measured fat cell turnover.
It was found that the number of fat cells in the human body was determined during the early years of life, so lean youngsters will develop less fat cells than overweight ones. However once adulthood is reached the fat cells stay constant.
So the weight you are as a child will impact on your weight as you get older. When someone puts on weight it is the size or volume of the fat cell that increases not the number of cells. Therefore if you have more cells to begin with you have more cells to store the lipids and increase the cell volume which in turn increases body mass..
However lean men who became obese during adulthood had the same problem with the increase in their fat cell volume but their fat cell count still remained the same.
The cells were also monitored during rapid weight loss such as through gastric band surgery and lower calorie intake and again although the weight was lost the cell count remained constant.
This may be a reason why some people loose or gain weight more rapidly than their counterparts, it actually comes down to the number of fat cells increasing or decreasing their volume.
In an adult there was a 10 percent regeneration of fat cells but neither fat cell death nor its generation rate is altered in early onset obesity, suggesting a tight regulation of the number of fat cells in obese adults.
These results could help researchers develop new pharmaceuticals to battle obesity as well as the accompanying diseases such as high blood pressure and diabetes.