Glycolic acid is used for its exfoliating effect in order to delete pigmented keratinocytes, increase the penetration of the other topical agents, at the same time as depositing hydrating agents inside the surface of the newly exfoliated skin, thereby reducing the appearance of fine lines, wrinkles and hyperpigmentations and improving sun-damaged skin
But 28 days is the conservative, widely accepted standard
Conditions like pernicious anaemia (an autoimmune disorder where your body cant absorb B12 from food), certain stomach conditions, medications that reduce stomach acid, or even gastrointestinal surgeries (like weight loss surgery) can prevent your body from properly taking in B12, even if youre getting enough in your diet
According to Mayo Clinics drug and supplement reference, intramuscular B12 (the form used in MIXTs B12 injection protocols) is well-established for restoring B12 status quickly in clinically deficient patients and is often used when oral supplementation is poorly absorbed