Solanum nigrum is the fruit edible?

Sergei, question number two. I've been reading about solanum nigrum, and there is a big debate in Italy wether its fruits are edible or not. here we have this thing about the plant being very poisonous. At a course I attended I asked the teacher and he said abosuletely its poison don't eat it. I told him in the rest of the world people eat the fruits, preserve them, make jams, but he said they must be hybrids of some sort.
I let it go hoping though to ask the question again to someone that might help me with this point. So what do you know of it, is it edible? or are there some species in the family its from that are poisonous and others not? I don't think the last one can be the point to it but its one of the answers I've had on this point, "maybe in the states they have an edible one and here its poisonous" i've been told.

The last time I ate Solanum nigrum berries I woke up about 6 hours later with the worst stomach ache I have had since my appendix was removed. I had eaten a large quantity raw. They were extremely sweet and tasty.

A few berries here or there didn't bother me, but a large batch was very troubling to me. So troubling, that I took a magic marker and wrote the name of the species on my chest: Just in case I died during the night. At least that way my family would know what had happened.

Black nightshades are found in Africa to India and beyond. Its leaves are used as a green, boiled twice or more like pokeweed.  In Kenya four varieties of it grow and three are highly sought after. It is the prime potherb. The fourth variety is considered too bitter to eat. Of 61 greens tested in Africa, S. nigrum had the highest amount of vitamin A. In the region of India the plant has many names and is firmly in the human food chain and very popular.

When Europeans arrived they saw the native nightshades.  Because they resembled the Black Nightshades in the Old World they were considered variations of the Old World nightshades and were called … Black Nightshades … all of them.  But as time passed botanists had different opinions and the names were changed, or worse combined, such as Solanum nigrum var. americanum. Every botanist with an opinion called these plants what he thought they should be called.  What was once thought of as varieties of one native in North American ( S. nigrum) became many plants with many names. Then even more careful botanists got rid of some of the names and said they weren’t Black Nighshades at all and were not Old World variations.  In fact, some think the S. americanum(ah-mare-ree-KAY-num) isn’t even a native but is from Australia. On top of that, the Old World plant, the original Black Nightshade, became naturalized in North America as well.  So it became quite a muddy soup. Then there were reports of toxicity, which makes some sense if you were calling non-Black Nightshades Black Nightshades, essentially inducting non-edibles into the edible group.  To say it is a foggy, foraging family is an understatement.

It is to be kept in mind, that nightshades (even Common sandwich tomatoes) are mildly toxic and an inflammatory, to all humans. I would personally keep it to topical medicines, unless properly IDed by a local botanists. Or experienced forager.

Lorenzo, I grow a plant or two every year and nibble the berries with no problems but have never eaten more than 2-3 at a time. Sam Thayer has discussed this plant at great length for greens and leaves and discussed the toxicity question; I think it's in Nature's Garden.
Some things with reputations for toxicity are not in fact poisonous: I have been flamed on a gardening website for mentioning the use of chile pepper leaves as a seasoning, but they are used this way throughout Southeast Asia and my Hispanic neighbors in New Mexico used them. Tomato leaves are also used as a seasoning and the New York Times did a very good article on the evidence that they are not in fact poisonous.
That said, i feel squeamish about eating any quantity of black nightshade greens or berries even though I believe (theoretically) that it would be safe. I can't explain this. Prior indoctrination I suppose.
Sergei, I would be most interested to hear about your experiences with this plant.

Here is a link to a permies thread that addresses solanum nigrum and a few similar plants.
In my location, the plants i have identified are fully edible. I have made a black nightshade jelly, eaten the steamed leaves, and eaten the berries raw without any ill effects.

As is mentioned in that thread lisutsa is the common name in Kenya for the leaf of black nightshade.

@heather
Yeah you have a good point about the myths of poison when we are talking about highly domestic species. A tomato now and its leaves are usually not analogous to a tomoto written about in the 1800s. Just as lettuce was considered medicinal and in fact it was back before it had been completely domesticated into what we see today.

@lorenzo
I have learned to be weary of people who are completely sure about things, especially things as complicated as nature. Was your teacher thinking of deadly nightshade? Are some s. Nigrums strong enough to be poison? Was the teachers experience with eating the berries unripe? You never can be sure when there are so many conflicting views.
With all plants i would say do your own research and identification until you feel totally comfortable that what you have is an edible species. Before i ate my black nightshades i became a tomb of information about the plants uses around the world and throughout history. Even after i had a complete id and background i still eased my way into eating it. Just as the kenyans do, i can eat a whole portion of s nigrum leaVes with a meal and feel only positive effects.

Zach, how do you prepare the leaves? Do you preboil as I have seen recommended?

Heather Ward wrote: Sam Thayer has discussed this plant at great length for greens and leaves and discussed the toxicity question; I think it's in Nature's Garden.

I know the book and found the chapter illuminating, I wanted to hear from Sergei or others what they think and if they know there may be poisonous species in Europe which I think is not possible
I'll read the link Zach thanks

I usually pick younger leaves and cook like a normal green. The young leaves do not have as much stem and end up tasting a lot like other boiled or steamed greens . I think for older leaves one might want to change the water to decrease bitterness.