She said: "Despite its negative reputation, not all worry is destructive or even futile. It has motivational benefits, and it acts as an emotional buffer.
"Worry can motivate proactive efforts to assemble a ready-made set of responses in the case of bad news.
"I don't intend to advocate for excessive worrying. Instead, I hope to provide reassurance to the helpless worrier."
Writing in the journal Social and Personality Psychology Compass, Professor Sweeny noted three possible explanations for worry's motivating effects.
People use their emotions when making decisions, and worry serves as a cue that the situation is serious, she said.
While it also keeps a stressor at the front of their mind, prompting them into doing something about what's bothering them.
The third reason could be due to the unpleasant feeling it creates pushing people to find ways to reduce their worry.
Worry can also benefit one's emotional state by serving as an emotional bench-mark, Professor Sweeny added.
Compared to the negative feelings of worry, any other feeling is deemed pleasurable by contrast.
In her paper, she likened worry to that of using a seat belt in terms of its preventative health benefits.
She pointed to a previous study that found those who worry about skin cancer were more likely to use sunscreen.
While other research has found women worried about breast cancer reported self-examining themselves more often.
