Brief Answer: Aspartame Detailed Answer: Hi, I have gone through your query. Beverages contain a substance called Aspartame. On taking large dose suddenly it is said to trigger the pain occasionally in some persons. Its effect varies from person to person. Most of the peoples complain of Dizziness and headache after consuming diet coke or pepsi. There is another theory that is immediately broke down into its metabolites and can trigger insulin secretion which in turn lead to sudden Hypoglycemia. Heavy sweating might be due to sudden fall of your uncontrolled sugar level. It is better to avoid beverages for the time being and if not, it happens again, drink plenty of water. Some studies suggested that Aspartame can cause neurological problems like seizures, mood change, panic attacks and headache. Hope I have answered your query. If you have any further questions i will be happy to help.

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