Two issues here. First the amount of sugar Americans are consuming and second, the safety of Splenda.
According to the USDA and several national nutrition surveys, Americans are consuming more sugar than any species has consumed in the history of the planet, averaging somewhere between 30 and 50 teaspoons of added sugar a day. That’s up to 150 pounds a year for every man, woman, and child of a substance that provides no nutritional value other than calories and has been linked to the epidemic of obesity, as well as a variety of diseases, including diabetes. It is critical that Americans cut way back on their calorie and sugar intake or the obesity epidemic will break the back of the healthcare industry in this country, as all the obesity experts are warning.
Second, Splenda is the safest sugar substitute available. It is a sucrose molecule with 3 extra hydrogens and a chloride attached. Most of it can’t breakdown and is excreted unchanged. In fact, sucralose is 85% unabsorbed and the other 15%, because it is water-soluble, does not accumulate in tissues, and is excreted within 24 hours. Its safety is so secure that it is approved in more than 80 countries, and has been approved for even vulnerable populations such as pregnant women, nursing women, and children. Since it is 600X sweeter than sugar, it requires very tiny amounts to sweeten foods (most of what you find in that packet is inert, safe filler, such as dextrin).
For those reasons, I typically choose sucralose, or Splenda, as a safe alternative to added sugar in recipes and as a way to cut back on calories, yet still maintain the super-sweet taste that Americans have come to demand.