According to biochemists who have analyzed metabolism at a microscopic level, fat can breathed out and can also burned off when people lose fat. But they have also given warning that still people require to huff and puff with exercise to keep themselves slim.
Chemical bonds are broken, a process which emits heat and fuel to power muscles. The route of fat out of the body has been traced by the Australian team as atoms. Some things take place when fat is broken down to its constituent parts.