Splenda is made from sugar, but by no means is it natural. It is ARTIFICIAL. Personally, I use Splenda and Nutrasweet, so I don't care. Both are better than sucrose when it comes to staying lean. New study just came out (Oct. 2002) comparing the use of sucrose (table sugar) and artificial sweeteners like aspartame, ace-k, saccahrin and the like. "Overweight subjects who consumed fairly large amounts of sucrose... had increased energy intake, body weigh, fat mass, and blood pressure after 10 weeks" than those who used artificial sweeteners. In the sugar group, fat increased by 1.3kg after 10 weeks and the artificial sweetener group lost 0.3kg of fat.
Raben A, Vasilaras T, et al. "Sucrose compared with artificial sweeteners." Am J Clin Nutr 2002;76:721-9.