Many nightshade plants are popular foods in most cultures, including tomatoes, potatoes, and peppers.
But they also contain high levels of substances called alkaloids that may cause health problems.
It’s not common, but some people have an allergy or sensitivity to nightshades.
alvarez / Getty Images
There is also some concern that these vegetables may contribute to inflammatory conditions, like arthritis.
This article discusses the health impacts of nightshade foods and how to determine if you have an allergy.
Plants produce alkaloids to protect themselves from mold, disease, and pests.
However, the concentration of alkaloids is higher in the stems, leaves, and unripe vegetables.
Some research claims eating a large number of green potatoes or potato tops may lead to toxicity.
While uncommon, some people may experience sensitivities or allergies to the alkaloids in nightshades.
In addition, some people may experience an allergy to the fruit or vegetable itself instead of the alkaloid.
For example, tomatoes contain the compoundlycopene, which may help lower heart disease and cancer risk.
Symptoms of an allergy occur when your immune system reacts to a harmless substance, such as a food.
Symptoms are not triggered by an immune system response.
Sensitivity and intolerance symptoms tend to be less severe than an allergy.
The symptoms primarily affect the digestive system.
One autoimmune condition that has been researched reagarding nightshades isinflammatory bowel disease(IBD).
So, its unclear if smaller doses cause the same increase in inflammation.
Nightshades are listed as foods to avoid in the Autoimmune Protocol Diet because they may worsen symptoms.
The treatment plan may also include medications to counter allergic reactions when exposed.
Types of nightshade plants include potatoes, tomatoes, peppers, red pepper flakes, eggplant, and paprika.
Symptoms of a nightshade allergy include congestion, skin rash, itching, redness, and digestive problems.
Food allergies are diagnosed with a skin prick test or blood allergy test.
They are treated by avoiding the allergen and medications to reduce the immune response.
A Word From Verywell
A nightshade allergy isn’t common.
Still, people who are sensitive to it could experience bothersome symptoms and increased inflammation.
If you are sensitive to nightshade foods, there are options for substituting these foods.
Talk with your healthcare professional if you believe you have a food allergy.
They can help determine if you do have an allergy and which foods to avoid.
Frequently Asked Questions
No, nightshades arent necessarily bad for you.
Alkaloids are most concentrated in nightshades like potatoes, tomatoes, and eggplant.
Many nightshade vegetables are high in vitamins, minerals, fiber, and antioxidants beneficial to health.
For example, tomatoes contain lycopene, which helps protect against heart disease and cancer.
Zang EH, Li QY, Xu JF, et al.
[A preliminary pharmacophylogenetic study of Solanaceae medicinal plants containing tropane alkaloids].Zhongguo Zhong Yao Za Zhi.
2021;46(17):4344-4359. doi:10.19540/j.cnki.cjcmm.20210623.103.
2020;4(Supplement_2):426-426. doi:10.1093/cdn/nzaa045_059
Fasano A.Leaky gut and autoimmune diseases.Clin Rev Allergy Immunol.
2019;11(4):e4556.
