Overview
Boiled crawfish, also referred to as crayfish, mudbugs and crawdads, are a traditional Louisiana Cajun dish, although it may be available throughout the United States. Predominantly a freshwater crustacean, crawfish resemble miniature lobsters, and the taste is similar as well, when boiled. The meat picked out of the shells has a sweet taste with a delicate texture.
Calories
A 4-oz. serving of boiled crawfish contains 91 to 93 calories. Melted butter commonly accompanies this dish, which adds 102 calories for each 1 tbsp. Ideally, you should average 300 to 600 calories per meal. Combine a serving of boiled crawfish with vegetables like broccoli or carrots and a starch -- a vegetable like potatoes or a slice of bread -- for a nutritious, balanced meal.
Vitamins and Minerals
Boiled crawfish serves as a good source of iron -- each 4-oz. serving provides you with 8 percent of the daily recommend value. The World Health Organization notes that up to 80 percent of the world's population may have an iron deficiency; it is the leading cause of anemia in the United States, according to the Centers for Disease Control and Prevention. Anemia causes fatigue, headaches and pale skin resulting from a lack of oxygen in moving through your body. A serving of boiled crawfish also contains 5 percent of the calcium you require each day. The calcium in your diet helps you maintain the strength of your teeth and bones.
Benefits
Crawfish contain omega-3 fatty acids, an essential fat for your health. Your body does not manufacture omega-3 fatty acids, so including foods high in this fat is vital. Omega-3 fatty acids may decrease your risk of developing heart disease, arthritis and some types of cancer, and it plays a critical role in brain function. It may also guard against depression and other mental disorders, as well as skin conditions and asthma.
Considerations
While your body needs cholesterol to function, many people consume too much. An overabundance can clog your arteries and lead to blockages, increasing your risk of heart disease. Include no more than 300mg of cholesterol in your meal plan each day -- a 4-oz. serving of boiled crawfish contains 142 to 153mg.
Crawfish generally contain low levels of mercury, but monitor the level of contaminants in the waters in which your crawfish are harvested. Do not consume boiled crawfish more than two or three times per week, particularly if you are pregnant.
Source : http://www.livestrong.com/article/333119-boiled-crawfish-nutrition/