A study led by Dr. Daniella Chusyd of Indiana University showed that an average Asian Captive Elephant carries less body fat than an average human.

Despite their massive size, the captivated elephants carried a lesser body fat percentage. Their counterparts in the forests are lesser obese due to their frequent activity.

Chusyd said she wanted to know why elephants in the zoo had lesser birthrates. It was thought that these elephants had lower birthrates due to obesity. Such a case is similar to what health experts say is happening with humans.

This is the first time that an elephant's fatness is measured. The task sounds simple when someone says the amount of water inf an elephant's body is to be subtracted from its body mass. Researchers had to give each animal a dose of heavy water, however, the team had to be creative in their approach so the elephants wouldn’t spill the liquid.

“We came up with the idea of using bread soaked with heavy water to deliver it to the elephants,” Chusyd said.

Before the heavy water treatments and up to 20 days after the experiment, the zookeepers had collected blood samples of the elephant. The results were drawn with the help of scientists at the University of Aberdeen.

An average male elephant carries 8.5% of body fat, slightly lesser than 10% in the females.

Of those in research, the female elephants were found to have a body fat between 2 to 25%. The males in the research had a slightly higher fat. In comparison, an average human has 6 to 31% of body fat.

The researchers also say that they were surprised that infertile female elephants carried the least fat. The cause of infertility among the elephants is unclear after all.