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Direct answer · critical

What causes a hangover

A hangover is not caused by ethanol. Ethanol is what makes you feel the effects of drinking. The damage comes from acetaldehyde, the toxic intermediate your liver produces while clearing ethanol.

Quick answer

What is happening

The actual cause

Your liver metabolizes ethanol in two stages. The first enzyme, alcohol dehydrogenase (ADH), converts ethanol to acetaldehyde. The second enzyme, aldehyde dehydrogenase (ALDH2), converts acetaldehyde to acetate — which is harmless and goes into normal metabolism.

The problem is that ADH is fast and ALDH2 has a fixed ceiling. When you drink faster than ALDH2 can keep up, acetaldehyde accumulates. Acetaldehyde is a Group 1 carcinogen, a reactive aldehyde that crosslinks proteins and DNA, and the actual molecular cause of the symptoms people call a hangover.

Top mitigators

Ingredients that address this, ranked

Coverage at a glance

How tiers compare for this mechanism

Tier coverage for What causes a hangover
GoalBest (Tier 1)Strong support (Tier 2)Situational (Tier 3+)
Acetaldehyde clearance L-Cysteine, NAC (N-Acetyl Cysteine), DHM (Dihydromyricetin), Sulforaphane
Glutathione support L-Cysteine, NAC (N-Acetyl Cysteine), Sulforaphane
Liver protection L-Cysteine, NAC (N-Acetyl Cysteine), DHM (Dihydromyricetin), Sulforaphane
Neurotransmitter modulation DHM (Dihydromyricetin)
Deeper science · In more detail

Why you feel what you feel

Acetaldehyde accumulation explains almost every symptom:

  • Nausea and headache — acetaldehyde is directly toxic to the

gut lining and triggers serotonin release in the brainstem emetic centers.

  • Flush, fast heartbeat — acetaldehyde triggers histamine release

and vasodilation.

  • Cognitive fog — acetaldehyde crosses the blood-brain barrier and

interferes with neural signaling.

  • Next-day anxiety and 3am wakeups — a separate mechanism, from

GABA-A rebound, stacked on top.

What to do about it

Every ingredient in the Afterburners protocol exists to reduce acetaldehyde exposure by one of three paths:

1. Trap it chemically. L-cysteine and glycine react with acetaldehyde directly. 2. Clear it enzymatically faster. DHM and sulforaphane raise ALDH2 activity and ALDH2 enzyme quantity. 3. Replenish glutathione. NAC and silymarin keep the liver's backup conjugation pathway running.

The protocol's design principle is that any one pathway can be saturated, so flood all of them at once.