What kinds of basic nutritional training, or overall-health training, exist?

I’ve had a long-time interest in health, including many forms of exercise, natural remedies and healing practices, and information about nutrition and eating. Since I’m fairly obsessive about learning everything I can about it (first thing I read on the news, first book I pick up in a store, lots of related college classes, internet procrastination, etc) and really passionate about it, I’ve often become an (informal) counselor for friends and family – particularly when people have easily remedied, lifestyle-related health problems or when they need to lose weight. That seems to be a really common topic! Since it comes up often enough, someone recently suggested I get some kind of formal training, so that I could make sure my knowledge/advice was well-founded (fill in any gaps) and to give some legitimacy to it. Maybe even have nutritionist/weight-loss guru/etc as a second career or income option.

Now, I’m a musician and 100% content with pursuing that professionally, and content having other areas of interest as side passions and hobbies. But this is intriguing, and some quick Google searching found Masters programs and 9-month intensive career-change programs, and of course lots of weight loss sites and such. I’m not interested in a bunch of science courses, nor graduate school round #2, but I like the idea of learning more and being able to help people more to improve their health (on a general, common-sense, natural-oriented, whole-lifestyle level – basic anatomy, exercises and stretches, comprehensive nutrition and meal ideas).

Anyone know about types of nutritional/health/etc programs? Non-degree or degree? Certificates? What training/experience is needed for relevant jobs? Other thoughts on the subject?

Thanks!