Is it unhealthy to eat the stalk on tomatoes, after you've taken everything green off. I mean the white stuff which you can out of the tomato.
As long as you haven't used any pesticides or other chemicals on the plant, they are safe to eat. For the record, so are many species of grass.
However, it probably doesn't have much in the way of nutritional value, and I know for a fact that it doesn't taste very good (personal experience on wondering if it would make a good tooth pick).
Quite simply, there are less rough ways to get non-soluble fiber. I imagine with a good deal of cooking to denature the structure of the stems might lead to something more palatable.
Do let us know if you come up with some good recipes.
I can't bring a source but I can tell you why people whom I know, cut them off. It could be two reasons one: It's harder than the rest of the tomato, they don't want to eat it Two: It could be that there is residue of chemical's from pesticides (maybe). But it doesn't have a risk as the tomato itself. This was the connection to the source, like the navel.
I read the article of Wikipedia which states that Tomatoes contain low amounts of tomatine and solanine. So it's propably not unhealthier than drinking one or two glases of wine each day.