Administering the hormone leptin to the brain through the principles of gene therapy may help individuals lose weight without having to up their risks of bone loss.

Extreme adult weight gain is linked with numerous outcomes that are detrimental to health. While various methods for weight loss like diet, physical activity and drugs have sprouted, these have not guaranteed long-term weight control and may lead to negative side effects such as degenerative loss of cancellous bones.

Bone loss is of particular concern among people who exhibit fluctuating weight because of the so-called "yo-yo diet," which is the cyclic loss and gain of weight. Such type of dieting raises bone health concerns because when an individual loses weight, the amount of bone lost will not be regained should weight increase again.

Researchers from the Oregon State University (OSU) and University of Florida wanted to know if there is a way to reduce excessive weight while still retaining bone density.

Leptin is a hormone that helps in the growth and maintenance of bones. Aside from these main functions, leptin also aids the body in terms of maintaining weight by providing the brain with information about the amount of fats present and if fat supplies are enough. People who gain weight appear to develop a resistance against leptin thus the brain cannot perceive correct data.

To investigate further on the role of leptin in weight control, the authors injected leptin directly into rats' hypothalamus and studied the impacts of the hormone on weight and bones.

The findings of the study showed that the rats that were administered with leptin exuded a weight loss of approximately 20 percent but did not exhibit any bone loss. These subjects were also found to maintain their weight and cut abdominal fat significantly.

"Using leptin at the level of the hypothalamus to control weight is where, at some point, we believe we're going to be able to control weight gain," said Urszula Iwaniec, the study's corresponding author and an associate professor at OSU. She added that the body loses weight when the brain tells it to, but if the brain said don't, the body won't follow even if the person wants to lose weight.

Such gene therapy is permanent and may entail risks and side effects that are yet unknown. Further studies are required prior to hailing the procedure as a treatment for human weight loss.

Russell Turner, co-author of the study and the director of OSU's Skeletal Biology Lab said this type of therapy may be less invasive than the likes of bariatric surgery. He emphasized, however, that it is for a lifetime and with that being said, the procedure may sound highly extreme.

The study was published in the Journal of Endocrinology on Tuesday, Oct. 20.