Hazelnuts contain vitamins, minerals, protein, fiber and healthy fats. They add a nutty and rich flavor to baked desserts. They can also boost the nutritional profile of a salad. According to the Hazelnut Council, hazelnuts provide many health benefits and are a good inclusion in the daily diet. Hazelnuts are relatively high in calories — at 178 calories per ounce; they provide 9 percent of the daily energy intake in a typical 2,000-calorie diet. Each ounce of hazelnuts boasts 4 grams of protein and 5 grams of carbohydrates, including 2.7 grams of beneficial dietary fiber.