When I first started looking into different types of diets (READ: NUTRITION PLAN/WAY OF EATING), I was curious to always see Nightshade Vegetables mentioned. One diet that I have talked about is the anti-inflammation diet, this diet does not contain nightshade vegetables. You might know what they are and what that means, but I have mentioned before that I am not a gardener. I am not a gardener and even more so I have no idea about vegetable families and their classifications and stuff. I keep having to look it up. What is a nightshade vegetable? 
Nightshade vegetables are from the Solanaceae Family. Nightshade vegetables contain a group of chemicals found in plants called alkaloids. There are different types of plant alkaloids, some being toxic. Plants containing alkaloids have been used for medicinal purposes as well as stimulates and poisons. Studies have proven that alkaloids can affect some of the functions in the body. Some people are more susceptible than others. These vegetables are thought to interfere with digestion, muscles, and joints. Nightshade vegetables promote inflammation in the body.
If you are susceptible to them it might be beneficial to limit consumption of these types of veggies. As I mentioned if you are on an anti-inflammation diet they might be forbidden all together. Again this could only be if you are sensitive to them. Or if you are interested in trying to reduce the amount of chronic inflammation in the body. If you have arthritis or any other disease associated with chronic inflammation it might be something to try. Or if you experience pain caused by sensitive nerves.
Nightshade vegetables are very common. They are so common it kind of makes sense that chronic inflammation is more prevalent and being study by the medical profession. I think the most common nightshade veggies are potatoes, tomatoes, and bell peppers. You know I LOVE bell peppers and I was just learning to like tomatoes. And the issue with potatoes is they are yummy in so many forms; mashed, fried, baked, roasted. In addition to my beloved bell pepper ALL peppers are lumped in this family. So even the hot ones that might aid in digestion could be causing inflammation issues.
In addition to inflammation there is research has proved that the alkaloid in potatoes interrupt signals from nerves to muscles and might contribute to muscle twitches. Next time you have a twitch try to remember if you had any potatoes. In addition to signal interruption, the chemicals contained in some nightshade vegetables might even cause pain Also some research has shown that the alkaloids leech calcium out of bones and deposit it into soft tissue.
Eggplant is also a nightshade vegetable. I love roasted eggplant. Eggplant along with tomatoes contain nicotine. Yup, tobacco is a nightshade plant and nicotine is an alkaloid. It is fortunate that both tomatoes and eggplant contain a lot less nicotine then tobacco, it is still interesting to know.
Cooking reduces the level of alkaloids in our veggies by about 40-50%.
Please note that I am not saying that any health issue or discomfort you are experiencing is caused by nightshade vegetables/food. What I am saying is that some research has either proved or associated the alkaloids in nightshade vegetables/foods to be connected to certain things; inflammation, digestive issues, nervous system malfunctions, pain, muscle twitching, etc. and it is interesting to know. And it might be beneficial to do some experimenting with your diet if you think you might be sensitive to the chemicals found in some of the vegetables and/or spices considered nightshade foods.
Did you know what veggies were considered nightshade? I am glad that I now have this list.
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