What ADH and ALDH Are
Alcohol dehydrogenase (ADH) is a family of zinc-containing enzymes that catalyze the oxidation of primary alcohols (including ethanol) to their corresponding aldehydes. In the human liver, ADH1A, ADH1B, and ADH1C are the three isoforms that handle most ethanol metabolism, with each isoform having slightly different kinetic properties1. Aldehyde dehydrogenase (ALDH) is a separate enzyme family that catalyzes the oxidation of aldehydes (including acetaldehyde, the product of ADH activity on ethanol) to their corresponding carboxylic acids. ALDH2 in the mitochondrial matrix is the dominant isoform for acetaldehyde clearance in the liver.
The two enzymes work in sequence. Ethanol enters the hepatocyte, ADH converts it to acetaldehyde, ALDH converts acetaldehyde to acetate, and the acetate enters general metabolism for breakdown into water and carbon dioxide. The pathway is short, the chemistry is well-mapped, and the rate-limiting step is usually ALDH at higher alcohol loads1.
Why the Genetic Variants Matter
Acts by promoting aldehyde and alcohol metabolism of foods.†
† These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
The clearest evidence that ADH and ALDH activity matters comes from the genetic variant literature. The ALDH2 variant common in some East Asian populations produces an enzyme with substantially reduced acetaldehyde-clearance activity. Carriers of the variant convert ethanol to acetaldehyde at normal speed but cannot clear the acetaldehyde efficiently, and the symptom severity (the so-called Asian flush response, but also longer-term elevated cancer risk) scales almost exactly with how much acetaldehyde accumulates2. The natural-experiment evidence that ALDH activity drives outcomes is unusually strong for this part of the cascade.
(this is the part of the biochemistry that finally made the formula click for me, because the upstream enzyme leverage point is more powerful than the downstream antioxidant buffering.)
What DHM Does to ADH and ALDH
Triggers the liver to produce more of the aldehyde- and alcohol-metabolizing enzymes (ADH and ALDH) and boosts their efficiency in breaking down aldehydes and alcohols in foods as well as their by-products.†
† These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
The ADH and ALDH finding comes from animal studies, and the results are mixed. A 2020 study in mice reported more of both enzymes in the liver, and lower ethanol and acetaldehyde levels, after DHM4. A 2020 rat study that gave DHM by mouth found no change in ADH activity or expression, and no drop in blood ethanol or acetaldehyde5. The 2012 paper by Shen and colleagues is often cited here, but it did not measure liver enzymes: it gave rats injected DHM, found that DHM counteracted alcohol intoxication, and found no significant change in blood alcohol at its main dose3. No study has measured these enzymes in people taking DHM.
The "boosts their efficiency" language in the H180 claim ties to two distinct things in the underlying literature: more enzyme molecules per cell (induction at the protein-expression level) and better substrate-handling per enzyme molecule. Both come from animal studies, not every animal study agrees, and neither has been measured in people.
The AST/ALT Connection
Lowers liver enzyme (AST and ALT) levels that are already in the normal range.†
† These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
AST and ALT are different enzymes from ADH and ALDH (different metabolic functions, different cellular locations) but they serve as serum markers of hepatocellular stress. When DHM is administered to animals during ethanol exposure, AST and ALT levels move toward normal compared to ethanol-only controls4. The proposed mechanism is indirect: if DHM speeds up acetaldehyde clearance through ADH/ALDH induction, there is less collateral cellular damage and less AST/ALT release into serum. That rests on the same mixed animal evidence as the enzyme finding above.
What This Page Is Not Claiming
The enzyme-induction claim is bounded to what the published animal mechanism literature supports, in DSHEA-compliant terms. We are not claiming DHM cures genetic ALDH2 deficiency, treats alcohol use disorder, or replaces the liver's natural enzyme function. The claim is that DHM upregulates the two enzymes that perform aldehyde and alcohol metabolism. The evidence for that comes from animal studies, and it is mixed.
For the full mechanism in detail, see How DHM Works -- The ADH/ALDH Pathway. For the headline aldehyde-metabolism claim this maps to, see Aldehyde Metabolism Explained.