Carrageenan is an additive that’s often used as a stabilizer or thickener. There’s a significant amount of hubbub about it within the past 10 years, but not really any science linking it to the claimed negative side effects (inflammatory issues, digestive issues, cancer being the most common). Basically the concern is whether or not this additive actually degrades in the body and therefore crosses the intestinal epithelium. At this time, there isn’t really enough research to provide guidance. If someone feels they are sensitive or may have inflammation issues, it wouldn’t be harmful to try removing it from their diet.
Sucralose is an artificial sweetener most frequently known as Splenda. Artificial sweeteners became popular when the world thought sugar was the enemy in everyone’s diet. We took out the real stuff and put in the fake stuff to still make things taste good. I’m sure we’re all aware of the claims related to artificial sweeteners. There is some evidence that artificial sweeteners have negative long term side effects. However, these have been mostly substantiated in animal trials with an excess amount of artificial sweetener consumed (waaaaayyy more than most humans would typically consume). They can certainly cause digestive distress though as they are meant to be calorie free and, therefore, indigestible. Personally, I think artificial sweeteners can be useful for those looking to decrease their added sugar intake. I still recommend all things in moderation though. A little bit of the real added sugar is fine, just like a little bit of the fake stuff is fine.
For both, I think the emphasis needs to be on fruits, vegetables, whole grains, meats, and water. As long as you’re consuming a balanced diet with an emphasis on whole foods with processed foods in moderation, neither ingredient should harm you.