It is a word use to describe people who seek foods high in micronutrients such as vitamins, minerals, phytochemicals, what humans need appears to be mainly a plant based diet. Other diets concentrate on the macronutrients, eg protien, carbohydrates etc, rather than the wellbeing and general health of the person.
To quote T Colin Campbell, author of the China Study:
"Nutrition ought to be the premier medical Science of the future"
See my blog at //www.curezone.org/blogs/fm.asp?i=1368959
for where this quote came from.
Also http://www.wellnessforum.com/
"Our mission is to empower people to take control of their health by providing up-to-date information about how nutrition, exercise and lifestyle choices impact health, longevity and quality of life."
This is the sort of thing this forum would be geared up to.