Native to China, cultivated in India and Africa, consumed in Europe, and practically unknown to America. That sums of the lychee, which is a sweet fruit whose only proven health benefit is vitamin C content; over 100% of your daily value per 3.5 ounces of them fresh. Given its high sugar and low antioxidant content, the fact that they're not for sale in the U.S. is nothing to cry over.
Research Support, Non-U.S. Gov't: Mahattanatawee K, Manthey JA, Luzio G, Talcott ST, Goodner K, Baldwin EA. Total antioxidant activity and fiber content of select Florida-grown tropical fruits. J Agric Food Chem. 2006;54(19):7355-63. NIH 2006