Deuterium-depleted water (DDW), also known as light water (or ”extra light water”, like our products, who have a very low Deuterium concentration) is water which has a lower concentration of deuterium than occurs naturally.
In “Vienna Standard Mean Ocean Water” VSMOW (*) deuterium occurs at a rate of 155.76 ppm. All natural occuring water, like drinking water has deuterium levels around this value.
(*) (VSMOW) is a water standard defining the isotopic composition of fresh water.