How do I apply for licensure as a nutritionist in Montana?

http://mt.gov/dli/bsd/license/bsd_boards/med_board/licenses/med/lic_nutr.asp

How can I be sure that someone is licensed to practice nutrition in Montana?

Check in Montana license lookup
http://app.mt.gov/cgi-bin/lookup/licenseLookup.cgi

How does Montana define and regulate the practice of nutrition?

By Statutes and by Rules
http://mt.gov/dli/bsd/license/bsd_boards/med_board/licenses/med/lic_nutr.asp