Aspartame is something that was left over from really unsavory cold war experiments, is my understanding of its origins. Wikipedia says it came from developing an ulcer medication. I suspect information was conflated a long time ago. Since Monsanto got NutraSweet when it bought Searle, and since they also produced a lot of toxic products, it was a logical conclusion. It is a really nasty product.

Staying cool this time of year means staying hydrated. I make a green tea with lemon balm tea in quart or half-gallon jars (two tea bags per quart, three for the half-gallon; a teaspoon or two of dried lemon balm in a tea sieve ball). To this I sweeten with a level measure scoop of stevia the same amount as tea bag (two scoops per quart, 3 scoops per half gallon). And I squeeze in a tablespoon or a little more of honey into it for the honey flavor. This comes out as a home-version of the Arizona brand green tea with ginseng and honey tea. (I don't have ginseng but the lemon balm grows all over the yard). There doesn't seem to be enough caffeine in the green tea to bother me at bedtime, though I usually don't drink it past about 5pm. Black tea is for mornings only here these days.