Gen Ys often get a bad rap for being lazy, but according to a new study they're addicted to being busy.

Two thirds of 18 to 29-year-olds surveyed say they feel high levels of stress and have a fear of missing out.

Health guru Dr Libby Weaver told Newstalk ZB it's vital people with hectic lifestyles make room for rest.

"The human body on a physical level needs to rest and we can't fight that aspect of our biology," Weaver said.

"So if we believe that we're under immense pressure and that everything is urgent then that will be the experience of our body and it will make the appropriate stress hormones."