Karen,

Since most people who malabsorb B12 do so because of insufficient stomach acid, and since really good iron absorption also depends on sufficient acid, they frequently go together.

With that type of malabsorption, problems could take many years or even decades to come on because of very slowly approaching B12 deficiency, especially slow because of processed foods fortified with B12 and the popularity of multivitamins and B complex. With that level of malabsorption, those could actually prevent deficiency.

But, for those who are not familiar with this information, that type of malabsorption progresses in some to severe malabsorption due to loss of intrinsic factor. When that is present, B12 from foods or even most vitamin supplements will not help at all. A much larger dose is necessary.

rose