Unlike the "B" it is apparently not adsorbed by fine precipitates such as fullers' earth or colloidal iron.
"The Vitamine Manual"
Walter H. Eddy
While fasting, it is essential to take steps to expel toxic mucous in the colon before the poisons are re adsorbed.
"How and When to Be Your Own Doctor"
Dr. Isabelle A. Moser with Steve Solomon