I was under the impression that this is not the case. Aspartame has been studied a lot and not found to be harmful.
Sugar is still the cultural default; artificial sweeteners are something you explicitly choose due to health concerns (worried about being or becoming diabetic, or overweight, or worried about sugar being unhealthy in general, or about the mood/motivation angle, etc.).
I imagine becoming overweight itself is linked to anxiety both ways, as eating or snacking is a common reaction to stress, a way to relieve it in the moment.
If only. Check the ingredients (usually near the bottom) of some energy drinks some time. Monster, NOS, AMP, half of the Rockstar flavors, Bang, and so on will add sucralose to the normal versions with sugar or HFCS in them. It's hard to find one without artificial sweeteners. This is especially crazy as Monster already has their sugar-free (Ultra?) line. They're forcing normal people to consume sucralose, and it's awful. Luckily Red Bull seems fine for now (Blueberry flavor is really good). Guru in its original flavor only also has no sucralose, but I think all the other flavors have it. I first noticed this trend one of the times they brought back Mtn Dew Game Fuel and it tasted disgusting. Now I'm scared of any new drink, or that they'll ruin one I like.
Also, I think water is fine, caffeine pills are fine, I know some people are against energy drinks, but I don't think that's a reason to ruin them (preempting replies saying not to drink them at all). I've been drinking black coffee all week but I still have some Blueberry Red Bull in my fridge for when I feel like it.
(Full disclosure: I consider red bull very high risk of being unhealthy, considering the stuff they put in, the artificial flavours, etc. – sucralose is a mere detail to me)
Ultimately, sweeteners won me over, and I've been "on" them for the past 12 years. For me it's a simple matter: I dislike pure water, and have been drinking black tea instead ever since I was a single-digit aged kid - but I also can't stand unsweetened tea. Sweeteners save me from ingesting stupid amounts of sugar through drinking some 10 mugs of tea every day, as I used to long ago.