[dpeck]

No idea, but theorizing “out loud”. Your body could be producing a bunch of insulin in response to the sweet, which lowers your blood sugar level to below normal levels since there’s no actual sugar for it to move around. Low blood sugar (< 70 mg/dl iirc) can lead to lightheadedness I believe, but folks who need to take insulin would be able to speak to that a lot more than I can.

I’ve seen some people say that they have an insulin response to artificial sweeteners but I don’t know if there’s any medical literature to confirm/quantify it.

[kayoone]

aspartam is not affecting the blood sugar though.

[MertsA]

But much more insulin than appropriate will lower blood sugar. This would be more of a question of whether or not aspartame causes an insulin response from the taste.