Your mom told you again and again growing up, and any nutritionist will tell you now—eat your veggies! After all, vegetables are packed with important vitamins, minerals, and other compounds that your body needs to function at its best.
One group of fruits and veggies, known as ‘nightshades,’ though, have gotten some shade (we had to) for supposedly triggering inflammation and worsening issues like digestive upset and joint pain. So, vegetables could be bad for some people? Say what?
Don’t go skipping over whole sections of the produce aisle just yet. These misunderstood veggies deserve a fair trial.
What Are Nightshades, Anyway?
Technically, nightshades are actually a family of flowering plants called Solanacae, explains Rebekah Blakely, R.D., dietitian for The Vitamin Shoppe. There are over 2,000 different species of plants in this family, but those that may often find their way into your shopping cart include potatoes (not sweet potatoes, though), peppers, tomatoes, and eggplants.
These foods contain compounds called glycoalkaloids that help protect the plant from their environment, including insects and pesticides, according to a paper published in the Journal of Acute Disease. While these compounds help the plant thrive, they might stir up trouble when we consume them. One glycoalkaloid in particular, called solanine, is the main recipient of the anti-nightshade hate. Though it can be toxic in large quantities (which is incredibly rare), solanine is typically fine in small quantities, says Blakely. You’re not about to go eat a wheelbarrow-full of potatoes, are you? We didn’t think so.
Most of the anti-nightshade hype actually focuses on another hot-button health topic: inflammation. Though there’s very little human research on the subject, the theory is that solanine disrupts a certain enzyme important to our nervous system, called cholinesterase, from doing its job, says Blakely. This in turn can lead to a slew of issues—including digestive upset and joint pain—which are often linked to inflammation.
Don’t Freak Out Just Yet, Though
This doesn’t mean you need to chuck all of those delicious nightshades. “These vegetables are healthy and provide a variety of vitamins and nutrients,” says Blakely. Tomatoes, for example, are a great source of antioxidants—including vitamin C, vitamin E, beta carotene, and lycopene. Peppers also contain similar antioxidant properties. Meanwhile, eggplants are a good source of B vitamins, and potatoes contain potassium, vitamin C, and vitamin B6, she says. All of these things do a body good!
While most people aren’t sensitive to the alkaloids in nightshades, they might affect those with inflammatory conditions. According to Blakely, people who have legitimate issues with nightshade foods are likely those who have not found relief for their inflammatory conditions through other methods. “If you do have an inflammatory issue, like rheumatoid arthritis or IBS, and have tried a lot of treatments but still have severe symptoms, I might recommend eliminating nightshades,” Blakely says.
If you have an inflammatory condition and want to try nixing nightshades, work with a dietitian who can help you do the job right. (They’ll likely also recommend eliminating dairy and gluten, —other common ‘issue’ foods for those with inflammatory issues—says Blakely.)
On an elimination diet, you’ll go up to two months without a certain food or food group—whether it’s nightshades, gluten, or dairy—depending on the severity of your symptoms. You’ll keep a journal to track your food and symptoms, and slowly reintroduce the eliminated foods once your two months is up. If you feel better without the eliminated foods, you’ll kiss them goodbye for good—but if you feel the same with and without eggplant in your life, there’s no reason to cut it out, Blakely says.
The bottom line: Unless you have an inflammatory condition, there’s no reason to cut out nutrient-packed nightshade foods like tomatoes, eggplant, peppers, and potatoes—especially since there’s very little research to suggest they have a negative impact on healthy humans. If you do have an inflammatory condition, talk to your doc and meet with a dietitian to assess whether an elimination diet is right for you.