found at www.deliciousorganics.com/Controversies/nightshade.htm and other internet locations
Natural toxins are normal. However, we can consume the fruit or vegetable safely when proper precautions are taken.
There are superstitious beliefs about the nightshade family (Potatoes, Tomatoes, Peppers, and Eggplant) and how they may harm the immune system or be unfit to eat. Actually, many of the vegetables in the nightshade family are staples in one's diet, particularly in the Middle East where Eggplant, Peppers and Tomatoes are eaten in abundance. These vegetables are also known for their great medicinal qualities. People following the macrobiotic diet don’t eat fruits, they are actually all fruits, in the nightshade family.
The nightshade family of foods do indeed have a potential toxin. This is mother nature’s way of protecting themselves from insect damage. The toxin is found in the green part of these vegetables. Proper choosing and storage can cut down these risks.
Potatoes should always be stored in a dark cool place and kept away from light. To be safe, any green part on the potato, including any growths, should be cut away before using. Don’t ever eat green potatoes , they contain the toxin solanine. Potatoes may turn green when exposed to light and you’ll see a green skin. Never eat the leaves or stems from a potato either.
Green Tomatoes have this toxin, glycoalkaloids. These toxins cause them to have a bitter taste to be unappealing for consumption. Although a delicious southern food (fried green Tomatoes), we should not consume green Tomatoes. And never eat the leaves or stems of Tomatoes.
Eggplant and Peppers should be ripe to avoid the toxin. That means no green Peppers and no green Eggplant. Green Peppers, though common, are actually just immature. When allowed to ripen they will turn a glorious red or yellow or orange or even purple. Green Peppers have a distinctive and strong flavor, not at all like the mature fruit which is sweet. There is, however, a variety of green pepper that is ripe when green. This is not the variety commonly found. The ones you find in most restaurants and grocery stores are red bells that are harvested at the unripe green stage.
Again, avoid the leaves and stems.
This toxin can cause nausea, vomiting, and headaches, but you have to eat a whole lot of it for this to occur. In super great quantities, they can cause convulsions and unconsciousness so it can be serious.
People with arthritis sometimes avoid these foods because they may aid in inflammatory conditions, but the reports are conflicting on this advice.
Sweet Potatoes aren’t in nightshade family, they are part of the morning glory family.
Personally, after researching this, I find nothing that leads me to believe the nightshade family is unsafe in average quantities and there is plenty of research on the great antioxidant value and nutritional value of this group, not to mention tasty and versatile!
Fun Fact:
Nightshade vegetables are actually all fruit! We eat them as vegetables (like in salads, side dishes, and not generally snacking out of hand or in desserts) so we consider them vegetables but they are indeed all fruit! What makes a fruit? It's all in the seeds and germination - fruits have seeds that develop from the "ovaries" of flowers. You'll also note that fruit get picked or snipped and leave the plant alive while vegetables, well, we're eating the entire plant there so there's nothing left. Other popular vegetables that are really fruit include okra, cucumber, summer squashhard squash. Fruitarians do eat these "vegetables" as well as nightshade "vegetables" because of that.