Nightshade Vegetables: Friend or Foe?

<script type="application/ld+json"> { "@type":"BlogPosting", "headline":"Nightshade Vegetables: Friend or Foe?", "datePublished":"July 11, 2019", "description":"Nightshade vegetables like potatoes, tomatoes, and eggplants have a reputation for causing harmful inflammation. Learn the truth about whether nightshades are part of a healthy diet.", "image": "https://d1ghrtdbdq2gkr.cloudfront.net/media/public/2019/06/nightshade-vegetables-thumbnail-0207.jpg" }, } ] } </script> <article> <div> <ul> <li><a href="#section1">What Are Nightshade Vegetables?</a></li> <li><a href="#section2">Why Are They Called Nightshades?</a></li> <li><a href="#section3">Are Nightshade Vegetables Bad for You?</a></li> <li><a href="#section4">Nightshades and Inflammation</a></li> <li><a href="#section5">What Are the Symptoms of Nightshade Intolerance?</a></li> <li><a href="#section6">Nightshades on the Low-Carb Diet</a></li> <li><a href="#section7">Should I Eat Nightshade Vegetables?</a></li> </ul> </div> <section> <p>You have to eat your vegetables!</p> <p>We’ve all heard it, especially as kids. That’s because vegetables are some of the best foods around, loaded with an array of nutrients, low in fat and calories, and just generally healthy.</p> <p>But just like not all fats are unhealthy, not all vegetables are good for you! The plants in the nightshade family, in particular, may cause health problems for some people. When figuring out your diet, it’s best to listen to your body and <a target="_blank" href="https://www.warriormade.com/content/diet/" rel="noreferrer">arm yourself with nutrition knowledge</a> to help you make the best choices for <i>you</i>.</p> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section1"> <script type="application/ld+json">{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"What Are Nightshade Vegetables?","acceptedAnswer":{"@type":"Answer","text":"Nightshade vegetables are foods that come from any of more than 2,000 plants in the Solanaceae plant family. Many of these fruits and vegetables (yes, tomatoes are a fruit!) can trigger inflammation or even autoimmune responses in people with sensitivities. In fact, we can only eat a fraction of the plants in the Solanaceae family because they’re so chemically potent!"}}]}</script> <h2>What Are Nightshade Vegetables?</h2> <p>Nightshade vegetables are foods that come from any of more than 2,000 plants in the <i> Solanaceae </i>plant family. Many of these fruits and vegetables (yes, tomatoes are a fruit!) can trigger inflammation or even autoimmune responses in people with sensitivities. In fact, we can only eat a fraction of the plants in the <i> Solanaceae </i>family because they’re so chemically potent!</p> <picture class="lazy-load"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/nightshade-vegetables-0207.webp" type="image/webp"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/nightshade-vegetables-0207.jp2" type="image/jp2"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/nightshade-vegetables-0207.jpg"> <img src="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/nightshade-vegetables-LR-0207.jpg" class="img-fluid" alt="nightshade-vegetables-0207"> </picture> <p>We also consume some nightshades as medicine or drugs: tobacco is a nightshade! But although nightshades contain some powerful chemicals, that doesn’t mean they’re necessarily bad for you—many of those substances have strong health benefits. Deciding whether nightshades fit into your diet is all about understanding both your body and the foods you eat. </p> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section2"> <script type="application/ld+json">{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"Why Are They Called Nightshades?","acceptedAnswer":{"@type":"Answer","text":"No one knows for sure where the name ‘nightshade’ came from. It might be because some of these plants prefer shady growing conditions or bloom at night. But others think nightshades were named because of the potent chemicals they contain.\n\nIn fact, some were used as deadly poisons for centuries. For instance, belladonna is a deadly European nightshade that was used in the Middle Ages by nobles vying for power, Game of Thrones-style!"}}]}</script> <h2>Why Are They Called Nightshades?</h2> <p>No one knows for sure where the name ‘nightshade’ came from. It might be because some of these plants prefer shady growing conditions or bloom at night. But others think nightshades were named because of the potent chemicals they contain.</p> <p>In fact, some were used as deadly poisons for centuries. For instance, <i> belladonna </i>is a deadly European nightshade that was used in the Middle Ages by nobles vying for power, <i> Game of Thrones</i>-style! </p> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section3"> <script type="application/ld+json">{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"Are Nightshade Vegetables Bad for You?","acceptedAnswer":{"@type":"Answer","text":"We don’t eat belladonna, though…so why should we worry about common foods like peppers and eggplant?\n\nWell, although not all nightshades are deadly, they do all contain chemicals that some people may be very sensitive to. These bitter substances called alkaloids are part of the plant’s natural defense against predators and pests. That means they can be highly toxic.\n\nAlkaloids like solanine, nicotine, and capsaicincan trigger inflammation or autoimmune responses in a small percent of the population. The worst culprits are glycoalkaloids, which combine a sugar molecule with an alkaloid. When your body digests the sugar, the alkaloid is left behind. It’s stored in the body with the potential to be released to wreak health havoc when you’re stressed.\n\nSolanine is one of the most well-known glycoalkaloids. Found in the leaves and stems of many nightshades, it’s relatively easy to minimize your exposure to solanine—we don’t usually eat nightshade leaves! However, this sneaky glycoalkaloid is present in green or sprouting potatoes, so if potatoes are part of your diet, make sure to never eat any that are tinged green.\n\nAlthough all nightshades contain glycoalkaloids, the same compounds aren’t present in every nightshade vegetable or in equal amounts. For example, green potatoes may contain dangerous amounts of solanine—but tomatoes and eggplant have less than ten milligrams, and peppers have even less than that 3. Despite their low solanine content, chili peppers contain high amounts of another glycoalkaloid, capsaicin. This spicy compound may make your mouth burn, but it’s actually great for your heart and metabolism—just one example of how we can’t say that all glycoalkaloids are bad for everyone all the time.\n\nEven if you don’t have a true allergy or sensitivity, you may want to be mindful of the nightshade foods you eat. That’s because glycoalkaloids like solanine can build up in the body and potentially cause an array of health problems."}}]}</script> <h2>Are Nightshade Vegetables Bad for You?</h2> <p>We don’t eat belladonna, though…so why should we worry about common foods like peppers and eggplant?</p> <p>Well, although not all nightshades are deadly, they do all contain chemicals that some people may be very sensitive to. These bitter substances called alkaloids are part of the plant’s natural defense against predators and pests. That means they can be highly toxic.</p> <p>Alkaloids like <i> solanine, nicotine</i>, and <i> capsaicin</i>can trigger inflammation or autoimmune responses in a small percent of the population. The worst culprits are <i>glycoalkaloids</i>, which combine a sugar molecule with an alkaloid. When your body digests the sugar, the alkaloid is left behind. It’s stored in the body with the potential to be released to wreak health havoc when you’re stressed ¹.</p> <p>Solanine is one of the most well-known glycoalkaloids. Found in the leaves and stems of many nightshades, it’s relatively easy to minimize your exposure to solanine—we don’t usually eat nightshade leaves! However, this sneaky glycoalkaloid is present in green or sprouting potatoes, so if potatoes are part of your diet, make sure to never eat any that are tinged green ² . </p> <p>Although all nightshades contain glycoalkaloids, the same compounds aren’t present in every nightshade vegetable or in equal amounts. For example, green potatoes may contain dangerous amounts of solanine—but tomatoes and eggplant have less than ten milligrams, and peppers have even less than that ³. Despite their low solanine content, chili peppers contain high amounts of another glycoalkaloid, capsaicin. This spicy compound may make your mouth burn, but it’s actually great for your heart and metabolism—just one example of how we can’t say that all glycoalkaloids are bad for everyone all the time ⁴.</p> <p>Even if you don’t have a true allergy or sensitivity, you may want to be mindful of the nightshade foods you eat. That’s because glycoalkaloids like solanine can build up in the body and potentially cause an array of health problems.</p> <picture class="lazy-load"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/woman-holding-stomach-inflamed-0207.webp" type="image/webp"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/woman-holding-stomach-inflamed-0207.jp2" type="image/jp2"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/woman-holding-stomach-inflamed-0207.jpg"> <img src="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/woman-holding-stomach-inflamed-LR-0207.jpg" class="img-fluid" alt="woman-holding-stomach-inflamed-0207"> </picture> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section4"> <h2>Nightshades and Inflammation</h2> <p>One of the most common issues caused by eating nightshade foods is inflammation. Many people believe that arthritis, digestive problems, bloating or puffiness, <a target="_blank" href="https://www.warriormade.com/content/diet/diet-and-lifestyle-affecting-your-brain/" rel="noreferrer">brain fog</a>, and other signs of chronic <a target="_blank" href="https://www.warriormade.com/content/diet/the-best-supplements-to-fight-inflammation/" rel="noreferrer">inflammation</a> are worsened by eating nightshade vegetables.</p> <p>But glycoalkaloids are tricky things—not everyone will experience issues after eating them. In fact, most people can safely consume plenty of potatoes, tomatoes, eggplant, peppers, tomatillos, and other nightshades and never notice a problem!</p> <p>However, if you’re one of the unlucky few who has a sensitivity, intolerance, or allergy, you may experience some very uncomfortable effects.</p> <p>It’s commonly believed that eating nightshade foods may be particularly unhealthy for people with arthritis or other joint conditions. Nightshades are thought to contribute to inflammation, but no scientific studies have proven this. In fact, one of the glycoalkaloids in hot peppers, capsaicin, has been proven to <i>relieve </i>inflammation ^{5, 6}!</p> <p>Where glycoalkaloids may become a real problem is in the <a target="_blank" href="https://www.warriormade.com/content/diet/inside-look-on-gut-health/" rel="noreferrer">gut</a>. People who are predisposed to gut inflammation issues like leaky gut syndrome and irritable bowel disease (IBD) may experience painful flare-ups after eating nightshade vegetables. </p> <p>Potato glycoalkaloids seem to be the worst offender here. Preliminary research seems to show that solanine and other glycoalkaloids in potatoes may make the intestinal membrane more permeable, allowing bacteria and acids to leak into the gut ⁷. They may also worsen existing inflammation. </p> <p>Although no human studies confirm this effect, it’s better to be safe than sorry when dealing with your health! Therefore, folks with IBD, IBS, Crohn’s disease, or leaky gut syndrome may want to avoid nightshades entirely.</p> <picture class="lazy-load"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/hot-peppers-in-hand-0207.webp" type="image/webp"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/hot-peppers-in-hand-0207.jp2" type="image/jp2"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/hot-peppers-in-hand-0207.jpg"> <img src="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/hot-peppers-in-hand-LR-0207.jpg" class="img-fluid" alt="hot-peppers-in-hand-0207"> </picture> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section5"> <script type="application/ld+json">{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"What Are the Symptoms of Nightshade Intolerance?","acceptedAnswer":{"@type":"Answer","text":"Even if you’re not allergic to nightshades, don’t have arthritis, and aren’t suffering from IBD or IBS, you may want to consider the effects of nightshade foods on your health. That’s because, just like with any substance, you may have a sensitivity or intolerance to glycoalkaloids that doesn’t quite reach the level of an allergy."}}]}</script> <h2>What Are the Symptoms of Nightshade Intolerance?</h2> <p>Even if you’re not allergic to nightshades, don’t have arthritis, and aren’t suffering from IBD or IBS, you may want to consider the effects of nightshade foods on your health. That’s because, just like with any substance, you may have a sensitivity or intolerance to glycoalkaloids that doesn’t quite reach the level of an allergy.</p> <p>Some of the key symptoms of nightshade intolerance include:</p> <ul> <li>Itchiness</li> <li>Nausea</li> <li>Bloating</li> <li>Stomach or gut irritation</li> <li>Diarrhea</li> <li>Heartburn</li> <li>Joint aches</li> <li>Nerve pain</li> <li>Lethargy or a feeling of fogginess</li> </ul> <p>To determine the cause of these symptoms, keep a food diary for three to four weeks. Write down everything you eat and how you feel after eating it, both soon after and later in the day. After a month, go back and look for patterns.</p> <p>Do you always feel bloated after eating salsa? Does eggplant parmesan make your joints hurt? Do you get heartburn after a spicy curry? You may have a nightshade intolerance!</p> <p>If that’s the case, your best bet is to talk to your health care provider. He or she may suggest you try an elimination diet, where you steer clear of all nightshade vegetables and foods for at least four weeks. Continue keeping your food diary during this time and see if your inflammation and health issues clear up. If they don’t, you may want to look for another culprit, like gluten or dairy intolerance.</p> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section6"> <h2>Nightshades on the Low-Carb Diet</h2> <p>As we’ve seen, the alkaloids and other potent chemicals in nightshades can be problematic for some people. However, for people who don’t have a true sensitivity or <a target="_blank" href="https://www.warriormade.com/content/diet/can-you-be-allergic-to-sugar/" rel="noreferrer">allergy</a>, nightshades can contribute to a healthy diet.</p> <p>That’s because those same glycoalkaloid compounds, as well as other <a target="_blank" href="https://www.warriormade.com/content/diet/keto-micronutrients-why-they-are-important/" rel="noreferrer">micronutrients</a> in nightshades, can support your body in a number of ways. Capsaicin can help boost metabolism and ease joint pain, while the lycopene in tomatoes can improve your heart health and lower your risk of cancer ^{8, 9}.</p> <p>Eliminating potatoes, a major source of potentially irritating glycoalkaloids like solanine, is a no-brainer for someone who’s going low carb. But what about other nightshade vegetables? </p> <p>Because many nightshade vegetables like peppers are low in carbs , they’re a good option for adding healthy flavor and texture to your meals on a low-carb or ketogenic diet. But be mindful of how you feel after meals! If you feel bloated or sluggish, have heartburn, or experience other symptoms of food intolerance after eating a dish with lots of eggplant, peppers, or tomatoes, you may want to try eliminating nightshade vegetables for a while.</p> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section7"> <script type="application/ld+json">{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"Should I Eat Nightshade Vegetables?","acceptedAnswer":{"@type":"Answer","text":"Low-carb nightshades like peppers, eggplant, and tomatoes can be healthy when consumed in moderation. They contain tons of antioxidants, and there’s even evidence that those potent glycoalkaloid compounds may fight cancer 10! But remember, nightshades are more than just potatoes! They can appear in many forms, especially in processed foods."}}]}</script> <h2>Should I Eat Nightshade Vegetables?</h2> <p>Low-carb nightshades like peppers, eggplant, and tomatoes can be healthy when consumed in moderation. They contain tons of antioxidants, and there’s even evidence that those potent glycoalkaloid compounds may fight cancer ¹⁰! But remember, nightshades are more than just potatoes! They can appear in many forms, especially in processed foods.</p> <ul style="width:45%; float:left;"> Nightshade Vegetables<br /> <li>Potatoes</li> <li>Tomatoes</li> <li>Peppers</li> <li>Eggplant</li> <li>Tomatillos</li> <li>Ground or husk cherries</li> <li>Okra</li> <li>Sorrel</li> </ul> <ul style="width:45%; float:left;"> Foods that Contain Nightshades<br /> <li>Marinara and other tomato sauces</li> <li>Ketchup</li> <li>Barbeque sauce</li> <li>Paprika</li> <li>Cayenne pepper</li> <li>Baba ghanouj</li> <li>Green chili</li> <li>Salsa (both red and green)</li> <li>Enchiladas</li> <li>Gumbo</li> <li>Curry</li> </ul> <p style="clear:both;">With all this in mind, <i>what’s the final word on eating nightshade vegetables</i>?</p> <p>Listen to your own body! You know what makes you feel good and what foods make you feel sluggish or unhealthy. Educate yourself to make smart nutritional choices, and you can use the foods you eat to give your body a boost.</p> <h3>Resources</h3> <ol> <li>Claringbold W, Few J, Renwick J. Kinetics and retention of solanidine in man. Xenobiotica. 1982;12(5):293-302. doi:10.3109/00498258209052469</li> <li>Yang X, Li J. A Case of Anesthetic Treatment of Appendicectomy to a Patient under Potato Poisoning. Case Rep Clin Med. 2015;4:137-140.</li> <li> Jones P, Fenwick G. The glycoalkaloid content of some edible solanaceous fruits and potato products. J Sci Food Agric. 1981;32(4):419-421. doi:10.1002/jsfa.2740320418</li> <li>McCarty M, DiNicolantonio J, O'Keefe J. Capsaicin may have important potential for promoting vascular and metabolic health: Table 1. Open Heart. 2015;2(1):e000262. doi:10.1136/openhrt-2015-000262</li> <li>Colpaert F, Donnerer J, Lembeck F. Effects of capsaicin on inflammation and on the substance P content of nervous tissues in rats with adjuvant arthritis. Life Sci. 1983;32(16):1827-1834. doi:10.1016/0024-3205(83)90060-7</li> <li>Jancsó N, Jancsó-Gábor A, Szolcsányi J. Direct Evidence for Neurogenic Inflammation and Its Prevention By Denervation and by Pretreatment with Capsaicin. Br J Pharmacol Chemother. 1967;31(1):138-151. doi:10.1111/j.1476-5381.1967.tb01984.x</li> <li>Patel B, Schutte R, Sporns P, Doyle J, Jewel L, Fedorak R. Potato Glycoalkaloids Adversely Affect Intestinal Permeability and Aggravate Inflammatory Bowel Disease. Inflamm Bowel Dis. 2002;8(5):340-346. doi:10.1097/00054725-200209000-00005 </li> <li>Janssens P, Hursel R, Martens E, Westerterp-Plantenga M. Acute Effects of Capsaicin on Energy Expenditure and Fat Oxidation in Negative Energy Balance. PLoS ONE. 2013;8(7):e67786. doi:10.1371/journal.pone.0067786 </li> <li>Lycopene: Health Benefits and Top Food Sources. Healthline. https://www.healthline.com/nutrition/lycopene. Accessed June 2, 2019.</li> <li> Friedman M. Chemistry and Anticarcinogenic Mechanisms of Glycoalkaloids Produced by Eggplants, Potatoes, and Tomatoes. J Agric Food Chem. 2015;63(13):3323-3337. doi:10.1021/acs.jafc.5b00818</li> </ol> </section> </article>