5. Individuals with Food Allergies or Sensitivities
Although uncommon, sensitivities or allergies to cruciferous vegetables can occur. Symptoms such as itching, swelling, or digestive discomfort are signs that intake should be reduced or avoided.

6. People Recovering from Gastrointestinal Surgery
After stomach or intestinal surgery, high-fiber foods like purple cabbage may irritate the digestive system. Consumption should be limited until full recovery.

In summary, purple cabbage is highly nutritious and beneficial for most people. However, individuals with thyroid conditions, digestive issues, kidney stones, or those taking blood-thinning medications should enjoy it in moderation, preferably in cooked form.