Stevia in Candidasis and Diabetes

Three questions please.
(1) Is stevia pronounced as in Steve or is it pronounced as in step?

We are not experts in Latin, but we believe the correct pronounciation is "stay-via". This would be what William Stearn calls (in his book "Botanical Latin") the 'reformed' or 'restored' academic pronunciation. This is a form of Latin that has been adopted by scholars as being reasonably close to how educated Romans spoke Latin.
However, Latin is widely spoken with an English pronounciation among gardeners. Like the Latin spoken in Europe in four or five hundred years ago, modern Latin takes on the bias of the dominant language, which in North America is, of course, English. So, while the reformed academic pronounciation of the long "e" is as in "they", the corresponding modern English-bias pronounciation is as in "me", which makes stevia more like "stee-via".
I often hear people using the short "e" as in "pet" so that stevia sounds like "steh-via". I do not believe that this is correct. The short "e", which is the same in both academic and modern Latin, occurs in Latin by complex rules that depend on the position of the vowel and on the origin of the word. Based on my limited knowledge of Latin, I suspect that the "e" in stevia is a long "e". Stearn does not list "Stevia" in his book so I am not completely sure of the correct pronounciation.

(2) What is its effect on people with candida, a fungus which is stirred up by sweet things?

Donna Gates, who developed the "Body Ecology Diet" for women suffering from candidasis, is a strong proponent of the use of stevia. She has written several books on using stevia in the diet.

(3) What is its effect on people with diabetes?

The steviosides in stevia are the sweet components. They have very little caloric value. They do not break down into glucose or other sugars. Stevia has been recommended widely for diabetics, but diabetics should seek the advice of a health care professional before starting to use stevia products.