Table 3.

Blood nutrient concentrations at baseline and at 12 weeks of supplementation and the effects of treatment on blood nutrient concentrations at 12 weeks (Medians and interquartile ranges (IQR); B values and 95 % confidence intervals)

	Control	Treatment
		0 weeks	12 weeks		0 weeks	12 weeks
	n	Median	IQR	Median	IQR	n	Median	IQR	Median	IQR	B (treatment effect)*	95 % CI	P †
Ferritin (μmol/l)	83	6·4	4·6–11·0	6·4	5·0–11·5	77	6·4	5·0–11·8	7·6	5·0–10·7	− 0·12	− 0·01, 0·26	0·074
Ferritin (μmol/l)‡	69	6·2	4·6–11·0	6·4	4·8–11·5	66	6·4	5·0–12·0	7·6	5·0–11·0	− 0·12	− 0·03, 0·27	0·128
β-Carotene (nmol/l)	85	390	305–470	440	340–540	80	385	323–470	470	380–610	47·1	6·5, 87·7	0·023
Retinol (ng/ml)	83	409	326–490	395	324–476	79	378	297–484	358	291–474	− 5·2	− 30·7, 41·0	0·777
Retinol (ng/ml)‡	69	421	319–537	396	324–466	68	375	309–485	367	291–476	1·0	− 38·7, 36·6	0·956
Ascorbate (μmol/l)	66	12·5	8·8–20·3	14·6	9·6–27·0	70	12·7	8·6–22·3	17·0	9·9–29·5	0·17	− 4·76, 5·10	0·947
Folate (nmol/l)	80	14·1	9·0–21·4	13·1	9·2–18·4	77	13·3	9·9–19·6	13·3	9·2–17·5	− 2·81	− 10·90, 5·28	0·755
Vitamin B12 (μmol/l)	79	250	178–351	255	187–304	76	290	228–340	259	208–326	19·02	− 11·61, 49·67	0·222
Hb (g/l)	88	114	103–125	119	106–126	82	114	105–122	117	108–123	− 1.60	− 4·90, 1·70	0·340

^*Treatment effects were estimated using ANCOVA models with the following covariates: baseline concentrations; age; BMI; compliance with supplementation protocol; use of micronutrient tablets; fruit intake at visit 3; green leafy vegetable intake at visit 3. Where ferritin and retinol concentrations were outcomes, C-reactive protein concentrations were included in the models.

^† P value relates to ANCOVA tests assessing the effects of the treatment groups on 12-week blood nutrient concentrations adjusted for baseline concentrations, age, BMI, compliance with supplementation protocol, use of micronutrient tablets, fruit intake at visit 3, and green leafy vegetable intake at visit 3.

^‡Excluding women with plasma C-reactive protein concentrations >5000 ng/ml.