A. Unless a big price hike accompanied the change, replacing sucralose with erythritol is likely to be to your advantage. Sucralose, marketed as Splenda, is being criticized because its slogan that it is "made from sugar, so it tastes like sugar" leaves the impression that it is a natural sugar. It isn't. It does not occur in nature but is made by treating sugar with chlorine, which prevents the body from burning it for energy. Because it tastes 600 times sweeter than sugar, very little is needed to obtain the same sweetness as table sugar. There are questions about its safety but no evidence of problems if it is used in reasonable amounts.
The ideal artificial sweetener would taste like sugar and be as sweet as sugar with no calories and no aftertaste. It would also dissolve easily in water, be stable when heated, not promote tooth decay, and be safe and economical to use. Erythritol seems to meet all these goals except the price.
Erythritol is a natural sweetener, found in fruit such as grapes, melons, and pears. Our diet typically supplies 50-100 milligrams of erythritol per day, which doesn't account for much sweetness. Erythritol is a sugar alcohol like sorbitol and some other sugar substitutes, but the molecule is smaller, with four carbons instead of six. Unlike sorbitol, erythritol does not provoke diarrhea or other stomach problems because it is easily absorbed. The big attraction of erythritol is that it is excreted in urine relatively unchanged, rather than being used for energy, so it contributes only 5% of the calories that the same amount of table sugar would supply. Erythritol is about 70% as sweet as table sugar so it takes a little more erythritol to have a food that tastes as sweet as ordinary sugar. At its present price, that makes erythritol about 50 times more expensive to use as table sugar. The price will probably come down some as it becomes more available. In 2004 the first plant in the U.S. to make erythritol from corn was built in Nebraska, which will probably help to bring the price down. Blending erythritol with other low-calorie sweeteners has the advantage of lowering the price of the mixture while improving the total sweetness and still having fewer calories.
Although it is possible that it reduces the absorption of boron, a trace mineral that has considerable effect on calcium metabolism, erythritol has been used in Japan with no problems for about 20 years and is presently on the "Generally Recognized as Safe" list in the U.S. Because it takes 800 times as much erythritol to equal the sweetness provided by sucralose, it is necessary for erythritol to be very safe indeed.
If you are using erythritol or any artificial sweetener in an attempt to lose weight, you should be aware that such foods increase the appetite in some people. It is not clear which hormones are involved, but apparently trying to "fool" the brain with artificial sweeteners tends to increase carbohydrate cravings. The key to losing weight is to burn more calories than you consume, either by increasing physical activity or consuming fewer calories, or (preferably) both.
