Many years ago I used Splenda before I understood what it was. Splenda is actually an artificial sweetener made up primarily of sucralose. It can cause abdominal cramping and bloating, headaches and other symptoms. If you're looking for a "healthy" product this isn't it. If you're glucose intolerant, for whatever reason, and just want to reduce your sugar intake, Splenda would work, but as I said, it has the same unhealthy effects as anything else artificial.
PS: You might also consider finding another doctor! This one sounds a little loopy