It was also initially believed that brown fat is only present in babies. Newborns have a significant amount of brown fat -- up to 5% of their body weight -- which helps to keep them warm.

Let’s see what’s so unique about this brown fat. Babies are born with brown fat to regulate their body temperature. (Shutterstock) This fat tissue is different from regular white fat.

"But you don't want preterm babies to do that," she said. "They don't have as much fat, minerals or iron, so they need extra nutrients." Currently, in the UK, breastfed premature babies are given ...