Crabs (Scientific Name: Brachyura) are rich in chromium and therefore are good for people with diabetes. They have plenty of selenium (an anti-oxidant) that cancels out carcinogenic effects of arsenic, mercury and cadmium. Crab meat like all shellfish has omega-3 fatty acids that reduce the stickiness of blood platelets. This means it is good for your heart. So in short, Crabs are good in fighting diabetes, cancer and heart diseases.
Many Seafood eaters prefer this because of the smooth and succulent meat it contains.