Low in calories, asparagus shoots are rich in beta-carotene, vitamins B, C and E, potassium, zinc and iodine. It is particularly rich in folate, the B vitamin that helps prevent neural tube birth defects and is therefore recommended for pregnant women. Seven spears provide around 70 percent of the daily recommended allowance.
It is also high in vitamin K, essential for blood clotting and bone health, and rich in the amino acid asparagine, a diuretic that helps dissolve uric and oxalic acids. This can be useful in the treatment of arthritis as the build up of these acids contributes to symptoms. It is asparagine that gives urine that peculiar smell after eating asparagus. It is also believed to be a natural aphrodisiac.