If you're not familiar with Naturopathy, read up on it in your native language here:
It is important that it convey that we are the world federation -- not a national or provincial association. The logo should look global and professional.
The logo should be classic and clean and highly professional without looking generic. Stay away from anything that looks like it could be clipart, stock, or free vector work.
The logo should balance the look of natural/holistic medicine and very classic, large organizations like ours.
This website has an example of a very classic, but a bit generic, emblem style logo:
We also like the stock photo in the upper right. The concept of holding the world/globe like an apple is interesting and maybe someone could elaborate on that for a pictorial style logo.
On this site, there is an example of a great letter style logo:
It's very classic and professional. This is a look we are interested in as well.
Please let us know if you have any questions.