I think that's incorrect
Just googles it this is what I got
What is the Recommended Dietary Allowance for vitamin B12 for adults?
The Recommended Dietary Allowance (RDA) is the average daily dietary intake level that is sufficient to meet the nutrient requirements of nearly all (97 to 98 percent) healthy individuals in each life-stage and gender group (7). The 1998 RDAs for vitamin B12 (in micrograms) for adults (7) are:
Life-Stage *Men *Women *Pregnancy *Lactation
Ages 19+ 2.4 mcg 2.4 mcg * *
All ages * * 2.6 mcg * 2.8 mcg
Results of two national surveys, the National Health and Nutrition Examination Survey (NHANES III-1988-91) (8) and the Continuing Survey of Food Intakes by Individuals (CSFII 1994-96) (7) found that most adult men and women consume recommended amounts of vitamin B12 (6-8).