OverviewShrimp are the most popular seafood in the United States, asserts the World's Healthiest Foods website. Shrimp are low in fat and calories and have a relatively neutral flavor that makes them a natural addition to salads, pastas, soups and stir-fried dishes.Macronutrients and Calories Four ounces of boiled or steamed shrimp contains just 112 calories. This serving provides nearly 24 g of protein and 1.2 g of fat--only 0.3 g of which is saturated. Shrimp contain no carbohydrates.Misconceptions Shrimp have a bad reputation for being high in cholesterol. In 1996, researchers from Rockefeller University concluded in a study published in the "American Journal of Clinical Nutrition" that consuming shrimp does not adversely affect cholesterol levels. The American Heart Association modified its dietary guidelines in 2001 to reflect that moderate consumption of shellfish, such as shrimp, can be part of a heart-healthy diet.Amino Acids Shrimp are an excellent source of the essential amino acid tryptophan. This amino acid is important to maintaining balanced sleep patterns and helps stabilize mood by affecting neurotransmitters in the brain according to "Psychology Today." The World's Healthiest Foods notes that 4 oz. of shrimp provides 103 percent of the daily recommended allowance of tryptophan.Other Nutrients A 4-oz. serving of shrimp is also a good source of vitamin B12, which can help protect against heart disease. A serving of shrimp also provides about 15 percent of your daily needs for omega-3 fatty acids and more than 60 percent of your daily needs for the trace mineral selenium, which enhances immunity, thyroid function and reproduction.Best Preparations Preserve shrimp's positive dietary qualities by sticking to steamed, broiled, boiled baked or grilled versions. Frying shrimp brings the calorie count for 4 oz. up to 317 calories with 17 g of fat. Smothering shrimp in buttery or creamy sauces also adds a lot of fat and calories to an otherwise diet-friendly protein source.