Randomized controlled trial of sour milk on blood pressure in borderline hypertensive men.
BACKGROUND
A double-blind randomized controlled trial was carried out to assess the effect of sour milk, containing two tripeptides (valine-proline-proline and isoleucine-proline-proline), on blood pressure (BP).


METHODS
A total of 46 borderline hypertensive men aged 23 to 59 years were recruited at their workplace for this trial. Subjects were randomly allocated into two groups; sour milk drink group (S-group, n = 23) and placebo (acidified milk) drink group (P-group, n = 23) for 4 weeks. Blood pressure was measured twice at each occasion by a physician, at the health center of the company, with a mercury at baseline, 2 and 4 weeks. Statistical analysis was performed by SPSS 10.0J.


RESULTS
The S-group and P-group showed no significant difference in baseline systolic BP (mean [SD], S: 147.6 [9.6], P: 145.3 [13.0]) or diastolic BP (S: 95.3 [9.9], P: 91.5 [9.6]). In the S-group, change in systolic BP at 2 and 4 weeks were -4.3 mm Hg (95% confidence interval [CI] -8.3 to -0.4; P = .032) and -5.2 mm Hg (95% CI -10.1 to -0.3; P = .039), both statistically significant. Diastolic BP showed change from -1.7 mm Hg (95% CI -5.4 to 2.0) at 2 weeks and -2.0 (95% CI -5.4 to 1.5) at 4 weeks, respectively. In the P-group, change in systolic BP were -0.5 (95% CI -5.8 to 4.8) at 2 weeks and -3.7 (95% CI -8.3 to 0.9) and change in diastolic BP were -0.6 (95% CI -4.7 to 3.6) and -0.3 (95% CI -3.9 to 3.3), which were not statistically significant.


CONCLUSIONS
This trial demonstrated the beneficial effect of sour milk on BP in borderline hypertensive men who were not taking antihypertensive medication.
International Research Center for Medical Education, The University of Tokyo, Tokyo, Japan. shunsaku-tky@umin.ac.jp
Shunsaku
S
Mizushima
Kenji
K
Ohshige
Junko
J
Watanabe
Maki
M
Kimura
Takashi
T
Kadowaki
Yasunori
Y
Nakamura
Osamu
O
Tochikubo
Hirotsugu
H
Ueshima
D000328:Adult; D000818:Animals; D001794:Blood Pressure; D019587:Dietary Supplements; D006801:Humans; D006973:Hypertension / Q000178:diet therapy*; D008297:Male; D008875:Middle Aged; D008892:Milk / Q000009:adverse effects; D010349:Patient Compliance