Effects of Black Currant Anthocyanoside Intake on Dark Adaptation and VDT Work-induced Transient Refractive Alteration in Healthy Humans

Alternative Medicine Review, Dec, 2000 by Hitoshi Nakaishi, Hitoshi Matsumoto, Shigeru Tominaga, Masao Hirayama

[Figure 2 ILLUSTRATION OMITTED]

Table 3: Dark Adaptation Values Measured Before and After Intake of BCA or Placebo in a Dark Adaptation Study.

Dose of BCA        Dark adaptation value, mean[Angstrom]}SD
mg/subject                of log asb; (p value)(1)

                    Before intake              After intake

0               2.056[Angstrom]}0.209      2.018[Angstrom]}0.218
(placebo)       (1.000)                    (1.000)
12.5            2.026[Angstrom]}0.147      2.004[Angstrom]}0.195
                (0.457)                    (0.761)
25              2.016[Angstrom]}0.170      1.980[Angstrom]}0.197
                (0.234)                    (0.264)
50              2.038[Angstrom]}0.186      1.923[Angstrom]}0.167
                (0.686)                    (0.014)

Dose of BCA       Dark adaptation value, mean[Angstrom]}SD
mg/subject              of log asb; (p value)(1)

                     Change, E[cts.]
                       [M.sub.dae]             p value(2)

0                 -0.038[Angstrom]}0.106          0.244
(placebo)         (1.000)
12.5              -0.023[Angstrom]}0.138          0.583
                  (0.733)
25                -0.037[Angstrom]}0.112           0.28
                  (0.983)
50                -0.115[Angstrom]}0.131          0.011
                  (0.171)

(1.) The results of statistical analysis, independently carried out in each vertical row, are shown in parentheses.

(2.) Statistical p value for "after intake" vs "before intake" in each horizontal row.

Transient Refractive Alteration Study

The age, sex, and refractive status of individual subjects are shown in Table 2. Refraction values for the dominant eye (designated as diopter (D)), measured before ([M.sub.tra]1) and after ([M.sub.tra]2) the visual task, and the changes ([M.sub.tra] = [M.sub.tra]1 - [M.sub.tra]2) are summarized in Table 4. Comparing [M.sub.tra]2 with [M.sub.tra]1, BCA intake resulted in no decrease in the average value after the visual task (from [M.sub.tra]1 of -0.432 [ or -] 0.602 D to [M.sub.tra]2 of-0.402 [ or -] 0.643 D, p = 0.598), whereas in the placebo trial after the visual task there was a large decrease in the refraction values, exhibiting borderline significance (from [M.sub.tra]1 of -0.384 [ or -] 0.536 D to [M.sub.tra]2 of -0.503 [ or -] 0.579 D, p = 0.064). Average changes ([M.sub.tra]) following intake of BCA and placebo were -0.030 [ or -] 0.252 D and 0.119 [ or -] 0.278 D, respectively, and a statistically significant difference was evident (p = 0.006).

Table 4: Refraction Values for the Dominant Eye, Measured Before and After the Task in Subjects Given BCA or Placebo, and the Change in Refractive Alteration.(1)