Table 2

Preintervention and postintervention period results of self-reported dietary intake and micronutrient concentrations by diet allocation

Low polyphenol
(n=47)
ChangeWithin-group p valueHigh polyphenol
(n=46)
ChangeWithin-group p valueBetween-group p value
PrePostPrePost
F&V intake*†
(portions/day)
1.38 (0.80)1.25 (0.57)−0.13 (−0.35 to 0.10)0.2521.40 (0.71)6.82 (2.12)5.42 (4.71 to 6.14)<0.001<0.001
Berries (portions/day)†‡000N/A01.00 (0.80 to 1.25)1.00 (0.77 to 1.25)<0.001<0.001
Dark chocolate
(g/day)†‡
000N/A050.0 (37.5 to 50.0)50.0 (37.5 to 50.0)<0.001<0.001
Epicatechin
(nmol/mol crt)*
0.12 (0.20)0.10 (0.12)−0.02 (−0.08 to 0.06)0.6290.10 (0.30)0.30 (0.29)0.19 (0.07 to 0.31)0.002<0.001
Vitamin C
(μmol/L)†§
25.1 (18.3 to 52.3)19.6 (11.8 to 48.9)0.79 (0.63 to 0.96)0.02128.4 (18.6 to 57.5)51.7 (43.9 to 68.6)1.82 (1.34 to 7.25)<0.001<0.001
Lutein (μmol/L)§0.16 (0.12 to 0.20)0.15 (0.11 to 0.20)0.98 (0.90 to 1.06)0.5950.15 (0.11 to 0.19)0.20 (0.15 to 0.26)1.32 (1.22 to 1.44)<0.001<0.001
Zeaxanthin
(μmol/L)§
0.04 (0.03 to 0.05)0.04 (0.03 to 0.05)0.97 (0.91 to 1.03)0.3310.04 (0.03 to 0.05)0.05 (0.04 to 0.06)1.18 (1.07 to 1.30)0.0010.001
β-Cryptoxanthin
(μmol/L)§
0.05 (0.04 to 0.08)0.05 (0.03 to 0.08)0.92 (0.83 to 1.03)0.1340.05 (0.04 to 0.07)0.07 (0.05 to 0.10)1.29 (1.15 to 1.45)<0.001<0.001
α-Carotene
(μmol/L)§
0.12 (0.09 to 0.16)0.11 (0.08 to 0.14)0.90 (0.82 to 0.99)0.0370.12 (0.10 to 0.15)0.14 (0.11 to 0.20)1.17 (1.05 to 1.30)0.0060.001
β-Carotene
(μmol/L)§
0.24 (0.15 to 0.36)0.21 (0.14 to 0.32)0.91 (0.82 to 1.01)0.0640.26 (0.19 to 0.36)0.30 (0.23 to 0.42)1.16 (1.05 to 1.28)0.0060.001
Lycopene
(μmol/L)§
0.45 (0.33 to 0.69)0.43 (0.33 to 0.58)0.95 (0.85 to 1.06)0.3430.47 (0.38 to 0.66)0.53 (0.41 to 0.69)1.12 (0.95 to 1.31)0.1770.098
Total carotenoids
(μmol/L)§
1.09 (0.84 to 1.47)0.99 (0.75 to 1.34)0.93 (0.86 to 1.09)0.8001.13 (0.91 to 1.36)1.32 (1.06 to 1.67)1.17 (1.06 to 1.29)0.0030.001
  • Bold figures signify significant p values.

  • *Normally distributed variables at baseline were summarised as mean (SD). Within-group change assessed using paired samples t test and between-group differences in change assessed using independent samples t test. Change expressed as mean difference (95% CI).

  • †Based on 92 patients due to incomplete food diary and insufficient Vitamin C sample in high-polyphenol group.

  • ‡Non-parametric data at baseline presented as median (IQR). Within-group change assessed using Wilcoxon signed-rank test and between-group differences in change calculated using Mann–Whitney U test. Change expressed as median difference (IQR).

  • §Skewed variables were logarithmically transformed and baseline values summarised as geometric mean (IQR). Within-group change assessed using paired samples t test and between-group differences in change assessed using independent samples t test. Change expressed as geometric mean (95% CI), which, due to the logarithmic transformation, represents the ratio of the post to pre value.

  • F&V, fruit and vegetables; N/A, not applicable.