The Truth About Nightshades and Poor Digestion

It might surprise you to find out that some people believe there is a link between eating nightshade vegetables and poor digestion. To shed some light on these "shady" rumors, we turned to registered dietitian, Sports Club/LA trainer, and lifestyle coach Julie Barrett.


Nightshade vegetables like potatoes (other than sweet potatoes), tomatoes, eggplants, sweet and hot peppers, eggplants, and chili-based spices such as cayenne and paprika contain a compound called solanine. While there isn't much research involving nightshade sensitivity, a study involving mice has shown that the solanine present in potatoes can affect intestinal permeability (leaky gut) and aggravate irritable bowel syndrome (IBS) symptoms when consumed in large doses. Nightshades also contain lectin, saponin, and capsaicin — three compounds that Julie says can be "problematic for someone who suffers from leaky gut."

Besides digestive woes, much of the debates around nightshades suggest that they interfere with enzyme activity in muscle and nerve tissue, resulting in pain and inflammation, which can worsen the effects of arthritis or even cause migraines. Again, there's a lack of scientific research that backs up these claims, and naturopath Dr. Andrew Weil adds that he has seen "little evidence that [giving up nightshades] is helpful."

Despite the lack of research substantiating any connection, many individuals still believe that nightshades are connected to their ailments. If you suffer from any type of inflammation, joint pain, or digestive issues, there's no harm in eliminating nightshades from your diet for a small period to see if your symptoms subside. However, Julie cautions that there are many other foods that can contribute to inflammation and leaky gut, such as gluten, dairy, and sugar. According to Julie, if you're concerned about developing a leaky gut and food intolerances, your best defense is to "maintain good integrity of the gut wall." This can be achieved through "stress management (stress is the leading cause of leaky gut), getting enough sleep for repair, avoiding processed foods, and getting enough prebiotic and probiotic foods."

Have you given up nightshade veggies and seen results? Let us know your experience in the comments!