If strictly looking at hydrogen consumption, inhalation will always be more effective. If drinking water is fully saturated with hydrogen (1.7ppm), 1 litre of that water provides the same amount of hydrogen delivered from 2 seconds of inhalation.
However, the effect Brown’s Gas has on the electric charge of the water is also important. Brown’s Gas will take water with a positive charge and change it to a negative charge. Essentially, by drinking bubbled water, you’re replacing an oxidizing agent with a reducing agent, or a litre of free-radicals with a litre of antioxidants.