Medica Health Plans is launching an aggressive program to help people kick the bad habits that can make them sick. Medica has hired and trained 30 professionals to work the phones as full-time "health coaches" to coax, cajole and inspire others to live healthier lives. Medica's program uses a computer program to identify which members of the plan need help the most. They'll get invitations in the mail to take part, at no cost. But critics say the program is like healthcare Big Brother.