Table 2.

Mean percentage of red blood cell membrane PUFAs in IBS-D patients before (pre) and after (post) 12 weeks of LFD, categorized by baseline fecal zonulin levels (N-FZ or H-FZ).

Red Blood Cell Membrane PUFAs (% rel)	Total Pre (n = 38)	Total Post (n = 38)	p	N-FZ Pre (n = 20)	N-FZ Post (n = 20)	p	H-FZ Pre (n = 18)	H-FZ Post (n = 18)	p	n.v. (% rel.)
C20:4n6 AA)	17.42 ± 0.76	16.60 ± 0.69	ns	17.01 ± 1.32	15.92 ± 1.06	ns	17.88 ± 0.71	17.37 ± 0.84	ns	13–17
C20:5n3 (EPA)	0.80 ± 0.08	0.91 ± 0.08	ns	0.92 ± 0.12	1.04 ± 0.14	ns	0.68 ± 0.09	0.76 ± 0.07	ns	0.5–0.9
n-6 PUFAs	28.45 ± 0.79	26.64 ± 0.64	0.010	28.25 ± 1.25	26.75 ± 0.85	ns	28.67 ± 0.99	26.53 ± 0.99	0.025	24–34
n-3 PUFAs	8.35 ± 0.55	8.52 ± 0.48	ns	9.74 ± 0.81 *	8.89 ± 0.81	ns	6.81 ± 0.57 *	8.12 ± 0.51	0.043	5.7–9
Total PUFAs	36.86 ± 1.05	35.59 ± 0.85	ns	37.47 ± 1.64	35.45 ± 1.32	ns	36.19 ± 1.30	35.76 ± 1.08	ns	28–39
AA/EPA ratio	28.50 ± 3.16	23.82 ± 2.55	ns	21.26 ± 2.21 ***	20.59 ± 3.07	ns	36.54 ± 5.72 ***	27.42 ± 4.11	0.048	<15
n-6/n-3 PUFAs ratio	4.17 ± 0.55	3.54 ± 0.22	ns	3.15 ± 0.22 **	3.51 ± 0.33	ns	5.31 ± 1.10 **	3.56 ± 0.29	0.002	3–4.5

LFD = low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet; AA = arachidonic acid; EPA = eicosapentaenoic acid; PUFAs = polyunsaturated fatty acids. Data are presented as the means ± SEM. The Wilcoxon rank-sum test was used to determine the p-value for comparisons of pre- and post-treatment data. The Mann–Whitney test compared the two subgroups before and after the diet. Statistical significance was set at p < 0.05. ns = not significant. n.v.: normal values. * N-FZ pre vs. H-FZ pre, p = 0.008; ** N-FZ pre vs. H-FZ pre, p = 0.006; *** N-FZ pre vs. H-FZ pre, p = 0.030. At the end of this study, no significant differences in PUFAs levels were found between the H-FZ and N-FZ subgroups.