Abstract
We examined the effect of a new enriched rice fortified with vitamins and minerals similar to the brown raw rice on blood pressure, hemoglobin, urinary corticosteroids and dark adaptation in 20 rural women aged 57 years on the average. They have engaged in farming and eaten hitherto a rice diet enriched solely with thiamine.
The results obtained after eating the new enriched rice for one year were (1) decrease of diastolic blood pressure from 81±3 (initial value) to 76±3 (final value) mmHg, (2) increase of hemoglobin from 13.2±0.2 to 14.8±0.3g/100ml, (3) decrease of urinary excretion of 17-OH corticosteroids from 2.4±0.1 to 1.1±0.1mg/8hr, (4) increase of urinary pantothenic acid from 0.31±0.08 to 1.11±0.34mg/8hr. Since the most pronounced change of the constituent in the new enriched rice was the increase of pantothenic acid compared with the former enriched rice, the above mentioned beneficial results might be ascribed mostly to the effect of increased pantothenic acid.
Concerning the effect of vitamin to lower the blood pressure, authors suggested the increased activity of parasympathetic nervous system as a result of sufficient supply of the vitamin. Parasympathetic stimulation is known often to counteract the sympathetic which can cause the arterial pressure to increase.
The threshold value of dark adaptation was decreased only slightly, i. e., from 8.6±0.8 to 7.7±1.1mm even after 9 months feeding. After the supplementation of vitamin A from this time the improvement of threshold value was so remarkable that the value decreased to 4.5±0.6mm (slightly subnormal value) at the end of the experiment. The results indicate the prevailing shortage of vitamin A among the people though their dietary supply of the vitamin was estimated to be nearly adequate to the requirement.
