TABLE 4.

Lactose contents in human milk for populations in the United States and Canada (1980–2017)

	Lactose
	1–6 mo		7–12 mo
Ref1	Mean	SD	Mean	SD	Method
Perrin et al. (98)	—	—	5.67	0.73	LC-MS
Dewey et al. (36)	7.56	0.29	7.49	0.51	Enzymatic colorimetric (Dahlqvist)
Nommsen et al. (35)	7.22	0.17	7.15	0.27	Enzymatic colorimetric (Dahlqvist)
Butte et al. (111)	6.51	0.20	—	—	Colorimetric (Biochemistry analyzer)
Gross et al. (92)	6.97	0.61	—	—	Enzymatic colorimetric
Ferris et al. (130)	6.67	0.67	—	—	Enzymatic colorimetric
Dewey and Lonnerdal (91)	7.17	0.51	—	—	Enzymatic colorimetric
Butte et al. (128)	6.59	0.24	—	—	Colorimetric (Biochemistry analyzer)

¹Ref, reference.