As far as I understand it the magnesium is a carrier (minimum absorbtion of magnesium) and the release of oxygen liquifies the old fecal matter.
If your colon is clean the oxygen will benefit the rest of your body. The oxygen is also good for the beneficial flora.
A few years ago I used the Oxypowder for the oxygen and I took 1 capsule several times a day.
On the cancertutor website they suggest taking Oxypowder for the oxygen.