As someone who has been fasting for years now, I was always under the assumption that the point of staying hydrated during a fast is to flush toxins out through your urine. There are only 3 ways to flush toxins out of your body, poop, urine, and sweat. If you aren’t eating you aren’t pooping as much, if you aren’t drinking you aren’t peeing, if you are sweating you are losing water and electrolytes and dehydrating yourself. What exactly is the purpose or benefits to dry fasting? How do you feel days into a dry fast? Do you abstain from physical activity?
There are steps before the elimination of toxins. These steps are controlled by enzymes:
>The liver plays an important rôle in protecting the organism from potentially toxic chemical insults through its capacity to convert lipophiles into more water-soluble metabolites which can be efficiently eliminated from the body via the urine. This protective ability of the liver stems from the expression of a wide variety of xenobiotic biotransforming enzymes whose common underlying feature is their ability to catalyse the oxidation, reduction and hydrolysis (Phase I) and/or conjugation (Phase II) of functional groups on drug and chemical molecules.
Detoxification pathways in the liver
The question is then whether dry fasting increases these enzymes activity.
It could be the case for the one called CYP3A4 which is an important enzyme of the phase 1 detoxification process.
In rats:>intervention with prolonged dehydration involving alternating between 24-hour cycles of water-deprivation and water ad lib for 1 week (cyclic water-deprivation; four 24-hour water-deprivation and three 24-hour water ad lib periods), increased expression of NFAT5 target genes […]CYP3A4 mRNA levels were noted to be elevated in the liver and kidney (11.8 ± 4.8-fold over water ad lib, n = 14, p = 0.04 and 2.2 ± 0.4-fold, n = 9, p = 0.02, respectively), with concurrent CYP3A protein and activity increase.