Sorry for the late reply teck. The wiki post is this:
http://ringofbrodgar.com/wiki/FEPIf you read the examples given, they *seem* to suggest that you need to eat different types of FEP's to reduce your required total FEP's. Certainly to the new players it reads that way. A re-write of those examples with some real numbers and an example that includes all the same FEP food types would clear that up in my opinion.
So I did some calculations: First food eaten is 30% reduction (18->12.6), second is ~21% reduction (12.6->9.9). There is a formula behind this, does anyone know the actual constants behind it? I'm not quite enough of a mathy to be able to pick it out. Square of the total foodbar is a good hint, but it doesn't line up with a reduction based off that alone. I think it would be a nice addition to the wiki.