Chives are related to onions, leeks and garlic, and the relationship is evident in the taste. They have a delicate onion flavor that is complemented by hints of garlic. Because their flavor is relatively mild, experts recommend that chives be added at the end of cooking. Chives are a nutrient-dense food. This means they are low in calories but high in beneficial nutrients like vitamins, minerals and antioxidants. One tablespoon containing 3 grams of chopped chives provides 1 calorie and less than 1 gram of fat, protein, or carbohydrate.