The United States Department of Agriculture (USDA) recommends two or three servings of meat, fish, or poultry per day. One serving of cooked lamb is equal to 85 grams and is about the size of a deck of cards. An average 85 grams serving of lamb contains about 176 calories, which is comparable to many other types of red meat and poultry.

Lamb is a great source of protein and essential vitamins and minerals. A regular 85 gram serving averages about 43% of the Recommended Daily Allowance (RDA) of protein. It also averages 74% of the RDA of vitamin B-12, 30% of the zinc, 30% of the niacin, 17% of the iron, and 15% of the riboflavin. In addition to this, the correct ratio of all eight of the essential amino acids is contained in lamb meat.

Many people are concerned with the saturated fat and cholesterol content in foods, which have caused them to reduce or eliminate their consumption of red meat. However, lamb and other red meats, when eaten in moderation, can definitely make a valuable contribution to ensuring a healthy, well-balanced diet. Only about 36% of the fat in lamb is saturated. The remainder of the fat is in the healthier forms of monounsaturated or polyunsaturated. When shopping for lamb, select lean cuts and use low fat cooking methods such as roasting, broiling, grilling, braising, or stewing.

The leanest cuts of lamb have an average of 70 to 80 mg. of cholesterol. This compares very well to a skinless chicken breast, which has 70 mg. of cholesterol per 85 gram serving. It is recommended that no more than 300 mg. of cholesterol per day should be consumed, so 2 or 3 servings of lean lamb per day allows plenty of room before reaching the maximum recommended level.

Lamb has less marbling than other meats, which means that most of the visible fat is contained on the outside edges. Trimming the excess fat is helpful in reducing saturated fat and cholesterol, however doing this before the lamb is cooked can make it tougher and less flavorful, especially if the meat is broiled, roasted, or grilled. It is usually preferable to trim the fat after cooking because the fat layer protects the meat from drying out during the cooking process. Some of the fat melts during cooking and is absorbed into the meat. This acts as a natural tenderizer, but also adds some saturated fat and cholesterol to the meat. Even when the fat layer is left on during and after the cooking process, it should not be consumed, for health reasons and because it is not very flavourful on its own.

Source http://www.recipetips.com/kitchen-tips/t-29-516/Lamb-Nutritional-Facts.asp