. 2016 Oct 27;57(2):451–462. doi: 10.1007/s00394-016-1328-4

Table 4.

Summary previous studies on folate intake and status in Sweden

Study type	n	Year	% (male)	Age (years)	Region	Plasma folate (nmol/L)^a	Fasting (yes/no)	Intake (µg/day)	Intake estimation method	References
Children and youths
Riksmaten barn	590	2003	51	4	National	n.d.	n.a.	158 (129–193)^a	4 day record	[9]
	889		50	8		n.d.	n.a.	186 (153–221)^a
	1016		51	11		n.d.	n.a.	173 (139–218)^a
Cohort European Youth Heart Study	194	1989–1999	0	16 ± 4^b	Stockholm and Örebro	n.d.	n.a.	227 ± 104^b	24-h recall	[26]
	185		100	16 ± 4^b		n.d.	n.a.	285 ± 109^b
	138		0	10 ± 4^b		n.d.	n.a.	206 ± 76^b	24-h recall and food record
	163		100	10 ± 4^b		n.d.	n.a.	205 ± 88^b
Pregnant
PregNut pregnant	176	2006–2009	0	<35	Larger Umeå area	n.d.	n.a.	277 (253–301)^c	66 item FFQ	[27]
PregNut pregnant incl suppl	176					n.d.	n.a.	423 (386–460)^d
PregNut non-pregnant	103					n.d.	n.a.	300 (274–326)^c
PregNut non-pregnant incl suppl	103					n.d.	n.a.	353 (316–389)^c,d
Case–control	921	1996–1998	0	Pregnancy week 6–12	Uppsala	8.7 ± 5.2^b	Yes	n.d.	n.a.	[28]
Adults
Riksmaten	625	1997–1998	0	>17	National	n.d.	n.a.	211 (176–250)^a	7 day record	[7]
Riksmaten	589		100	>17		n.d.	n.a.	223 (185–266)^a
HULK 7 d record	842	1989	0	15–74	National	n.d.	n.d.	187 (127–270)^e	7 day record	[6]
HULK 7 d record	809		100	15–74		n.d.	n.d.	218 (146–321)^e
The Swedish Mammography Cohort	61,433	1987–1990	0	41–74	Västmanland/Uppsala county	n.d.	n.a.	234 ± 50^b	67 item FFQ	[5]
Malmö Diet and Cancer cohort	11,307	1991–1996	0	≥50	Malmö	n.d.	n.a.	287 ± 318^f	Diet-history method: 7 d record 168 item FFQ and interview	[4]
Malmö Diet and Cancer cohort	408		0	62 ± 4.9		12.2 ± 8.1^g	No	227 ± 62^g DFE = 307 ± 447^d,g	Diet-history method: 7 d record 168 item FFQ and interview	[29]
Cohort NSHDS	1791	1985–	100	25–74	Norrbotten/Västerbotten	8.0 (5.9–10.9)^a	Yes and no	244 (198–306)^a	65–84 FFQ	[8]
	1055	1985–	100	>59		8.3 (6.3–11.5)^a		n.d.	n.a.
	729	1985–	100	≤59		7.6 (5.8–10.3)^a		n.d.	n.a.
	826	1985–	0	25–74		8.8 (6.3–12.2)^a		226 (179–274)^a	65–84 FFQ
	497	1985–	0	>59		8.8 (6.2–13.0)^a		n.d.	n.a.
	329	1985–	0	≤59		8.8 (6.6–11.7)^a		n.d.	n.a.
Cohort Betula	961	n.d.	47	35–80	Umeå	14.4 (7.6–46.8)^h	No	n.d.	n.a.	[30]
Elderly
Cohort	161	n.d.	43	77 ± 6	Älvkarleby	8.8 ± 4.4^b	Yes	n.d.	n.a.	[31]

Plasma folate concentrations were measured using immunoassays

n.d. no data, n.a. not applicable, FFQ food frequency questionnaire

^aMedian (Q₁, Q₃); ^b mean ± stddev; ^c mean ± 95% CI; ^d folic acid × 1.7/DFE; ^e median (P10–P90); ^f crude mean ± stddev; ^g geometric mean ± stddev; ^h median (P5–P95)