(AP) – Researchers are reporting success with using cash incentives to help people lose weight.

In a yearlong study, people were offered a chance to win or lose $20 a month if they met certain diet goals. They lost an average of 9 pounds compared to just over 2 pounds for other study participants who were not offered the chance to win money if they shed pounds.

The diet study involved 100 obese employees at the Mayo Clinic.

Offering incentives is a tactic that many employers, insurers and Internet programs use to entice people to change bad habits like smoking or not exercising. Mayo researchers say it is important to keep the incentives going to maintain healthy changes.

The study will be discussed this weekend at a medical conference in San Francisco.