Vials and pipette on a lab bench
Illustrative image.
On this page
  1. The same element, different proportions
  2. What is heavy water?
  3. What is DDW?
  4. The idea to remember

The same element, different proportions

Hydrogen has several isotopes. Deuterium, noted as ²H or D, is a stable form of hydrogen that has an extra neutron. In natural water there is a small natural amount of deuterium. When comparing types of water, it counts the proportion of the isotope, not just the name on the label.

What is heavy water?

Heavy water is water in which the proportion of deuterium is much higher than in natural water; its formula is often written as D₂O. It is associated with industrial and research contexts. It is not synonymous with regular drinking water and should not be confused with DDW.

What is DDW?

Deuterium-depleted water has a declared deuterium concentration below a natural reference level. The direction is opposite to heavy water: it is not enriched, but has reduced deuterium. The PPM and the analysis method are the useful data for comparison.

The idea to remember

Heavy water and DDW are not the same thing. The compositional difference does not by itself prove a therapeutic effect; for health claims, relevant human studies are needed.

Disclaimer: This material is educational. It does not diagnose, treat, or replace the recommendations of a health professional.
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