SpiritualHeartYogi
Do them when it feels necessary.
At times I will do one every single day for a week straight and sometimes I will go a whole entire month without one. Listen to your bowels. I personally think that their a great tool for cleansing, not only your physical body but also for your emotional body. All of the emotions in which you felt during the times of consuming those past foods will also be released with the excess fecal waste.
Yes there are many so-called 'experts' who will tell you that it is not good for your body and that your colon will become dependent on them. That is not the case for me. It's only you, your body and your personal experience. Good luck