Eating hazelnuts in moderation usually has no side effects, but eating too much hazelnuts may cause indigestion, obesity and other discomforts, and it is recommended that those who are allergic to hazelnuts should avoid eating hazelnuts. Usually eat hazelnuts in moderation will not produce side effects, hazelnut protein content of 20.0g/100g, fat content of 44.8g/100g, in the same kind of food is in the front position. In addition 100g hazelnut contains 2411KJ energy, 7.4g water, 24.3g carbohydrate, 3.5g ash, 0.62mg thiamine, 2.50mg niacin, 0.14mg riboflavin and other nutrients. Because hazelnut calories, protein, fat and other nutrients, if you eat too much hazelnut may also cause indigestion, obesity. People who are allergic to hazelnuts should avoid eating hazelnuts to prevent allergic reactions such as itchy skin, rashes, breathing difficulties, laryngeal edema, etc. after eating hazelnuts.