On 20 Nov 2001, at 8:30, toni mettler wrote:

> So, my questions is are sweet potatoes and yams considered potatoes?

Only by those who like to use naming to promote confusion between
unrelated species.

> What about purple potatoes?

There are many species of potato is places like Peru which is a
centre of diversity.   All potatoes currently in production are crosses.
 A local joke is that a successful New Zealand potato is a cross
between a Scottish variety and an Australian or Mexican variety.   To
get tubers to set the variety must be matched to day length hence the
cross between varieties with shorter and longer day length than ours.

There is a resurgence in growing old varieties maintained by Maori
tribes in New Zealand.  One of these varieties is a purple-fleshed
potato that has some frost resistance.

>And are they quick insulin elevating as  well as white potatoes?

I suspect their GI is less though I have no proof of it.

>Are they also not good for those with insulin  resistance struggles?

"Yams" is a confusing title applied to completely different plants in
different countries.  New Zealand yams are related to the oxalis
weed.    As a T2 diabetic I find I can have small quantities of both
orange fleshed sweet potato and New Zealand yams.   YMMV.

Quentin Grady