Walk into any farmer's market, and you will likely be in awe of the colors and variety of fresh vegetables available. Everything here looks like a healthy alternative to processed foods. Consume many types of vegetables from this market, and you will be on the road to health, right? Not necessarily. Nightshade vegetables may contribute to food sensitivities and allergies in some individuals. At the very least, you should be aware of what nightshade vegetables are and whether you should consume them in large quantities.



Everyone loves potatoes, whether they are French fries, home fries, hash browns, tater tots, or mashed potatoes. They are the perfect side for almost every meal. However, you may not realize that white, red, yellow, and blue-skinned potatoes are nightshades. Uncooked potatoes contain solanine; a toxic alkaloid merged with sugar. While solanine is not immediately toxic in small amounts, it can be stored in the body and slowly released during stressful conditions and situations. Some people believe that even small amounts of solanine in the body can worsen inflammatory diseases or aggravate joint stiffness in people with arthritis. However, scientific evidence of this is lacking. It's possible that some people are sensitive to low levels of solanine and should avoid foods that contain them. Potatoes that are turning green or are growing sprouts should be thrown away and not consumed, as these contain heavy amounts of solanine. Peeling potatoes also greatly reduces the solanine content as most of this toxic alkaloid is found in the skin.



While technically, tomatoes are a member of the fruit family, they are one of the most popularly consumed nightshade vegetables. Whether they are raw, cooked, or in ketchup or salsa, tomatoes also contain solanine. In addition, tomatoes contain tomatine, which is similar to chlorophyll. Fried green tomatoes and the stems and leaves of the tomato plant have the highest concentrate of tomatine. However, the fruit of the tomato can contain trace amounts. Research in animals shows that large quantities of tomatine can irritate the digestive tract and cause drowsiness or confusion. However, humans would have to consume a pound or more of tomatoes to develop signs of toxicity.



Peppers come in many different varieties, including bell, jalapenos, habaneros, cayenne, and paprika. Since bell peppers do not really pack a punch with heat, it may be hard to believe that they are part of the nightshade pepper vegetable family. An active ingredient in hot peppers, including the jalapeno, habanero, and cayenne, is capsaicin. It is one of the strongest alkaloid substances in food and herbs. After eating a hot pepper, it is no surprise that the capsaicin triggers irritants that cause a person to feel heat or a burn in the mouth and stomach, but did you know it also [has anti-inflammatory properties? Capsaicin is one of the ingredients in many pain-relieving gels and creams.



Like the tomato, the eggplant is also a fruit and a nightshade vegetable. It also contains solanine, which in large amounts may aggravate joint stiffness in some individuals, although this hasn't been scientifically proven. After eating eggplant, it is not uncommon for some people to complain of itchy skin or mouth, a mild headache, or stomach upset. Eggplant, especially uncooked, has a high concentration of histamines. Sometimes people complain about getting contact dermatitis from just touching eggplant leaves. Cooking the eggplant helps to remove most of the histamines, but it is likely that some remain.


The tomatillo is a nightshade that is a staple in Mexican green sauces. It grows in a husk and is very similar to the tomato. Tomatillos can be enjoyed in enchilada dishes and even salsa. Again, it likely contains the arthritis irritant, solanine. People who are prone to food allergies might experience troubling symptoms after eating tomatillos, including difficulty in breathing, skin rashes, hives, diarrheas, and swelling and itching in the mouth area.

Goji Berries

Goji berries are a nightshade with nutritional qualities including large amounts of Vitamins C and E. People add goji berries to oatmeal, cereal, and yogurt. Like the raisin, you can also bake with goji berries. These nutrient-rich berries also contain lectins, proteins that bind to carbohydrates. Some sources say to avoid foods that contain lectins, as they can irritate the digestive tract and reduce mineral absorption. Some people also believe they may worsen inflammation in people with inflammatory disease or arthritis. However, many foods that contain lectins are nutrient dense and have other health benefits. You can reduce the lectin content of foods by soaking and cooking them well.


The tamarillo is a South American nightshade that is low in calories compared to the tomato. It contains more seeds than a tomato and is comparable in taste to mango or apricot. Scooping the flesh from the fruit is the best way to eat or use a tamarillo. While a tamarillo seems more like a fruit, it does contain solanine and tomatine, like tomatoes. People with certain food allergies may want to avoid tomatillos, especially if they experience symptoms after consuming.


Pimentos, another pepper member of the nightshade family, are usually enjoyed in stuffed green olives or the southern specialty, pimento cheese. While pimentos do contain capsaicin, they do not pack as much of a punch as other hot peppers. A pimento's flavor may be similar to a bell pepper's, even though it looks like a hot pepper. Even if you do not enjoy pimento cheese, stuffed green olives often contain pimentos. Everybody likes the occasional cocktail, right? Go ahead, have that martini with an olive twist.


While you are not going to smoke a nightshade vegetable, did you know that almost every nightshade contains trace amounts of nicotine? Maybe that explains why French fries and ketchup are so addicting. Of course, the amount of nicotine consumed in potatoes and tomatoes is not equal to that inhaled in a cigarette.

Myth: Nightshades Contribute to Osteoporosis

It has become a common belief that nightshades contribute to osteoporosis. This is because nightshades contain oxalates, compounds that bind to calcium in the digestive tract and reduce its absorption. But, this is unlikely to be a problem for people consuming enough dietary calcium. So far, there isn't enough scientific evidence to say that nightshades contribute to or worsen osteoporosis.


This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.