Hazelnuts (hazelnuts) can be harmful if consumed in excess or with certain health conditions. Some potential risks of hazelnuts: 1. Allergic reactions: Hazelnuts are a major food allergen and can cause severe reactions, including anaphylaxis. 2. Digestive issues: High fiber content can lead to bloating, gas, diarrhea, or constipation, especially in those with sensitive digestion or IBS. 3. Oxalate content: Hazelnuts contain oxalates, which may contribute to kidney stone formation in susceptible individuals. 4. Caloric density: Hazelnuts are calorie-rich, so overeating them without adjusting overall calorie intake can lead to weight gain. 5. Potential for contamination: Hazelnuts can be contaminated with aflatoxins, toxic compounds produced by molds, which are linked to liver damage and an increased risk of liver cancer. Precautions: People with known nut allergies, kidney stones, or taking certain medications should consult a doctor before consuming hazelnuts.