An increasing number of companies are keeping tabs on their employees' eating habits and fitness routines to reduce healthcare costs. Several U.S. workplaces recently started using armbands to monitor employees' physical activity. Ane one healthcare firm bought spending data on millions of people in its employer group plans, sending weight loss information to those who bought plus-size clothes or junk food. Some companies, like Johnson & Johnson, offer pay incentives to workers who submit certain health details or get important medical procedures like colonoscopies. While it's all part of an effort to encourage healthy habits some say this monitoring of personal data feels like a privacy invasion.