Table 4.

Estimated vitamin B12 intake by time since birth in exclusively breastfed^a infants of mothers not using vitamin B12 containing dietary supplements (n = 89).

Time since birth months	Mean milk intakes L/db	B12 concentration in human milk mean (SD)	Estimated B12 intake from human milk μg/d
1 (n = 9)	0.699	490 (274)	0.47 (0.26)
2 (n = 33)	0.731	328 (160)	0.33 (0.16)
3 (n = 13)	0.751	249 (75)	0.25 (0.08)
4 (n = 14)	0.780	260 (85)	0.28 (0.09)
5 (n = 11)	0.796	283 (129)	0.31 (0.14)
6 (n = 9)	0.854	205 (44)	0.29 (0.06)
Total	0.780	308 (159)	0.31 (0.15)

^aEighty percent (n = 140) of the infants were exclusively breastfeed and 66% (n = 92) of the mothers used no supplements, two women were excluded due to intake of high vitamin B12 containing supplements and one women with high MMA.

^bBased on milk intakes of exclusively infants from developed countries, WHO, 2002 [16].