I think it was potassium that was the reason I craved, but pineapple is very good for you...see below
Pineapple fruit contains a proteolytic enzyme bromelain that digests food by breaking down protein. Bromelain also has anti-inflammatory, anti-clotting and anti-cancer properties. Studies have shown that consumption of pineapple regularly helps fight against arthritis, indigestion and worm infestation.
Fresh pineapple is an excellent source of antioxidant vitamin; vitamin-C. 100 g fruit contains 47.8 or 80% of this vitamin. Vitamin-C required for the collagen synthesis in the body. Collagen is the main structural protein in the body required for maintaining the integrity of blood vessels, skin, organs, and bones. Regular consumption of foods rich in vitamin-C helps the body protect from scurvy; develop resistance to combat infectious agents (boosts immunity) and scavenge harmful, pro-inflammatory free radicals from the body.
Further, ananas fruit is rich in the B-complex group of vitamins like folates, thiamin, pyridoxine, riboflavin and minerals like copper, manganese, and potassium. Potassium is an important component of cell and body fluids, helps controlling heart rate and blood pressure. Copper is an essential cofactor for red blood cell synthesis. Manganese is a co-factor for the enzyme superoxide dismutase, which is a very powerful free radical scavenger.