It’s not common, but some people have an allergy or sensitivity to nightshades. 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.
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Nightshade Allergy Causes
Most of the concern about nightshades appears to focus on a substance called alkaloids.
Plants produce alkaloids to protect themselves from mold, disease, and pests. The common types of alkaloids found in plants are:
Most people experience no negative health effects after eating nightshades because the alkaloids are eaten in small amounts relative to body size.
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.
In addition, some people may experience an allergy to the fruit or vegetable itself instead of the alkaloid.
Common Edible Nightshades
While some nightshade plants may contain higher amounts of alkaloids, they also contain other vitamins and minerals important for your overall health and well-being. For example, tomatoes contain the compoundlycopene, which may help lower heart disease and cancer risk.
Here are some of the most popular nightshade fruits, vegetables, and spices:
Symptoms of a Nightshade Allergy
People with an allergy to nightshades may experience symptoms after eating a food from the nightshade family, like:
Sensitivity and intolerance symptoms tend to be less severe than an allergy. The symptoms primarily affect the digestive system. Anightshade intolerancemay cause symptoms such as:
Effects of Nightshade on Autoimmune Diseases
Despite the health claims that nightshades increase inflammation and may aggravate anautoimmune disease(a condition in which the immune system mistakenly attacks the body), the research is still limited to support these claims.
A mouse study suggested nightshade vegetables may increase intestinal inflammation and worsen IBD symptoms.One drawback to this study is that researchers used a larger proportion of alkaloids in the mice than the average person would take in from food. So, it’s unclear if smaller doses cause the same increase in inflammation.
Some research suggests that increases in intestinal inflammation increase the likelihood for autoimmune diseases to develop.So, if nightshade vegetables do increase inflammation, they may raise the risk for autoimmune diseases such asrheumatoid arthritis,celiac disease, andHashimoto’s disease.
While there isn’t enough research to determine if nightshade compounds cause or worsen autoimmune diseases, if you are concerned, you may wish to consider reducing them to see if this decreases your symptoms.
Nightshades are listed as foods to avoid in the Autoimmune Protocol Diet because they may worsen symptoms. This diet is a modification of the Paleolithic diet (focusing on whole foods and non-processed meats) and begins with the elimination of specific foods.However, the effect isn’t scientifically proven.
Diagnosis of Nightshade Allergies
With any food allergy, you’ll want to start keeping a journal to track any patterns you notice among your diet, your lifestyle, and your symptoms. Nightshade allergies are rare, so you’ll also want to look at more common allergens, like dairy, nuts, seafood, soy, and gluten.
Your healthcare professional may recommend allergy tests to help diagnose a specific allergy, such as:
Treatment for Nightshade Allergies
The typical treatment plan for food allergies involves avoiding foods containing the allergen. Your healthcare professional may ask you to keep a food journal to monitor your symptoms and any potential symptom triggers.
The treatment plan may also include medications to counter allergic reactions when exposed. Common medications that may be prescribed include:
Food Substitutions for Nightshade
Substituting other foods for nightshades can be simple when you know the right fruits and vegetables to use. Here are some easy swaps for popular nightshade foods:
Summary
A nightshade allergy is an immune response to the compound in nightshade plants called alkaloids. Types of nightshade plants include potatoes, tomatoes, peppers, red pepper flakes, eggplant, and paprika.
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 QuestionsNo, nightshades aren’t necessarily bad for you. Some people withallergies, intolerances, or autoimmune diseases may experience adverse reactions when eating nightshades, but there is limited research to support these effects.Learn MoreNightshade Foods and ArthritisAlkaloids 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.
Frequently Asked Questions
No, nightshades aren’t necessarily bad for you. Some people withallergies, intolerances, or autoimmune diseases may experience adverse reactions when eating nightshades, but there is limited research to support these effects.Learn MoreNightshade Foods and Arthritis
No, nightshades aren’t necessarily bad for you. Some people withallergies, intolerances, or autoimmune diseases may experience adverse reactions when eating nightshades, but there is limited research to support these effects.
Learn MoreNightshade Foods and Arthritis
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.
5 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.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.Imran M, Ghorat F, Ul-Haq I, et al.Lycopene as a natural antioxidant used to prevent human health disorders.Antioxidants(Basel). 2020;9(8):706. doi:10.3390/antiox9080706Li S, Wang T, Xu B, Indukuri V, Vanamala J, Reddivari L.Anthocyanin-containing purple potatoes ameliorate dss-induced colitis in mice.Current Developments in Nutrition. 2020;4(Supplement_2):426-426. doi:10.1093/cdn/nzaa045_059Fasano A.Leaky gut and autoimmune diseases.Clin Rev Allergy Immunol. 2012;42(1):71-78. doi:10.1007/s12016-011-8291-xAbbott RD, Sadowski A, Alt AG.Efficacy of the Autoimmune Protocol Diet as part of a multi-disciplinary, supported lifestyle intervention for Hashimoto’s thyroiditis.Cureus. 2019;11(4):e4556. doi:10.7759/cureus.4556
5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.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.Imran M, Ghorat F, Ul-Haq I, et al.Lycopene as a natural antioxidant used to prevent human health disorders.Antioxidants(Basel). 2020;9(8):706. doi:10.3390/antiox9080706Li S, Wang T, Xu B, Indukuri V, Vanamala J, Reddivari L.Anthocyanin-containing purple potatoes ameliorate dss-induced colitis in mice.Current Developments in Nutrition. 2020;4(Supplement_2):426-426. doi:10.1093/cdn/nzaa045_059Fasano A.Leaky gut and autoimmune diseases.Clin Rev Allergy Immunol. 2012;42(1):71-78. doi:10.1007/s12016-011-8291-xAbbott RD, Sadowski A, Alt AG.Efficacy of the Autoimmune Protocol Diet as part of a multi-disciplinary, supported lifestyle intervention for Hashimoto’s thyroiditis.Cureus. 2019;11(4):e4556. doi:10.7759/cureus.4556
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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.Imran M, Ghorat F, Ul-Haq I, et al.Lycopene as a natural antioxidant used to prevent human health disorders.Antioxidants(Basel). 2020;9(8):706. doi:10.3390/antiox9080706Li S, Wang T, Xu B, Indukuri V, Vanamala J, Reddivari L.Anthocyanin-containing purple potatoes ameliorate dss-induced colitis in mice.Current Developments in Nutrition. 2020;4(Supplement_2):426-426. doi:10.1093/cdn/nzaa045_059Fasano A.Leaky gut and autoimmune diseases.Clin Rev Allergy Immunol. 2012;42(1):71-78. doi:10.1007/s12016-011-8291-xAbbott RD, Sadowski A, Alt AG.Efficacy of the Autoimmune Protocol Diet as part of a multi-disciplinary, supported lifestyle intervention for Hashimoto’s thyroiditis.Cureus. 2019;11(4):e4556. doi:10.7759/cureus.4556
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.
Imran M, Ghorat F, Ul-Haq I, et al.Lycopene as a natural antioxidant used to prevent human health disorders.Antioxidants(Basel). 2020;9(8):706. doi:10.3390/antiox9080706
Li S, Wang T, Xu B, Indukuri V, Vanamala J, Reddivari L.Anthocyanin-containing purple potatoes ameliorate dss-induced colitis in mice.Current Developments in Nutrition. 2020;4(Supplement_2):426-426. doi:10.1093/cdn/nzaa045_059
Fasano A.Leaky gut and autoimmune diseases.Clin Rev Allergy Immunol. 2012;42(1):71-78. doi:10.1007/s12016-011-8291-x
Abbott RD, Sadowski A, Alt AG.Efficacy of the Autoimmune Protocol Diet as part of a multi-disciplinary, supported lifestyle intervention for Hashimoto’s thyroiditis.Cureus. 2019;11(4):e4556. doi:10.7759/cureus.4556
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