We’re often reminded of the many benefits of eating fruits and vegetables. But could some actually work against us?
Nightshades – like tomatoes, potatoes and peppers – are packed with nutrients, yet they sometimes spark debate over whether they are bad, inflammatory or the cause of some health problems.
So what’s the truth? Are nightshades a healthy choice or a food group to avoid? With the help of Amanda Spina, a registered dietitian with Banner Health, we break down the facts, nutritional benefits and whether you need to think twice before adding nightshades to your plate.
What are nightshades?
Nightshade plants belong to the Solanaceae family, which includes more than 2,000 species. Common nightshade vegetables include tomatoes, potatoes (not sweet potatoes), eggplants and various types of peppers, such as bell peppers and chili peppers. Spices made from peppers, like cayenne pepper, paprika and chili peppers, are also included in this family.
“Some species of nightshades are non-edible – like the deadly nightshade belladonna and tobacco – and should be avoided, but most edible nightshades are safe and nutritious,” Spina said.
While we often think of nightshades as vegetables, many varieties like tomatoes and peppers are technically fruits because they develop from flowers and contain seeds. In this blog, we refer to them as nightshade vegetables.
The health benefits of nightshade vegetables
Nightshades, like other plant foods, provide us with a lot of essential vitamins and minerals.
“They also contain phytonutrients and antioxidants, which help protect cells against damage and certain cancers. They are also high in fiber which supports gut health, heart health and blood sugar control,” Spina said.
- Tomatoes: Packed with vitamin C and potassium, tomatoes contain lycopene, a powerful antioxidant linked to heart health.
- Potatoes: Known for their potassium content, potatoes are a dietary staple in many parts of the world and contribute to heart and muscle health.
- Eggplants: High in fiber and manganese, eggplant also contains anthocyanins, which may help protect cells from damage.
- Bell peppers: These vibrant vegetables are rich in vitamin C and carotenoids, which support the immune system and eye health.
Why do nightshades get a bad rap?
Some nightshade plants are poisonous because they contain high levels of compounds called alkaloids, including solanine, which is often why the whole family of plants may seem guilty by association. Some people also think nightshades cause inflammation or swelling.
Overall, there is no hard evidence they are bad for your health. As we’ve shared, edible nightshades contain many nutritious benefits. The concentration of alkaloids like solanine is very low, especially if the produce is ripe. So it’s very unlikely you’ll eat too many alkaloids.
“Most nightshades are often blamed for inflammation but there isn’t enough research to support this,” Spina said. “Perhaps what is more surprising is that many of their antioxidant properties are proven anti-inflammatory and may help prevent inflammatory diseases.”
Who should avoid nightshade vegetables?
For most people, nightshades are safe and nutritious. However, you might be more sensitive to these foods if you already have an inflammatory or autoimmune condition like arthritis, psoriasis or inflammatory bowel disease. In addition to nightshade sensitivity, some people are allergic or intolerant to nightshades.
If you notice discomfort after eating nightshades, consider an elimination trial. For a few weeks, remove nightshades from your diet and slowly reintroduce them to see if symptoms return. An elimination diet is best performed under the direction of your health care provider or a registered dietitian.
“If cutting out certain nightshades relieves unwanted symptoms, there’s a good chance you are at least sensitive to them,” Spina said. “This could also indicate that an inflammatory condition is going on underneath the surface and needs to be addressed.”
If you don’t have any symptoms, don’t worry. Include nightshades in your healthy diet.
Ways to enjoy nightshade vegetables
“Most of the alkaloid compounds are present in the leaves, stems, flowers, skin and seeds, so avoiding these parts of the plants can reduce alkaloid exposure,” Spina said.
If you’d like to include nightshades in your diet but worry about potential sensitivities, try these tips:
- Peel potatoes and remove any green areas or sprouts, as these parts contain higher alkaloid levels.
- Remove seeds from bell peppers and tomatoes if you’re sensitive, as they may contain more alkaloids.
- Choose ripe produce to avoid higher alkaloid levels found in unripe nightshades.
- Cook nightshades instead of eating them raw. Cooking reduces alkaloid content and may be easier to digest.
“If you need to avoid nightshades for any reason, the great news is that there are many other plant foods that provide similar nutrition,” Spina said. Leafy greens, carrots and squash are great alternatives for a nutrient-rich diet.
The bottom line
Nightshades are a flavorful, nutrient-rich plant food that many people enjoy without issue. Packed with vitamins, antioxidants and fiber, they can support heart health, immune function and overall well-being. So unless you notice symptoms after eating nightshades, there’s no reason to shy away from these veggies (and fruits!).
If you’re curious about how certain foods affect you, listen to your body and consider discussing it with your health care provider or a Banner Health specialist. They can help you make informed decisions about your health.
