Oral administration of hydrolyzed rice bran prevents the common cold syndrome in the elderly based on its immunomodulatory action.

The preventive effect of Hydrolyzed Rice Bran against the common cold syndrome was examined in elderly people. Arabinoxylan derivatives of Hydrolyzed Rice Bran (HRB) were prepared from water-soluble rice bran through partial processing using a carbohydrate complex. Using the water-soluble Rice Bran (RB) as a control, a cross over double-blind study was conducted on both substances over a 6-week administration period. Fifty elderly people aged from 70 to 95 years participated in the study and the comparative data from 36 participants were analyzed. There were no withdrawals from in the study due to the side effects of the experimental foods. Symptoms were observed and scored. The total symptom score for the RB treatment group was three times higher than that for the HRB treatment group. The average duration of symptoms was 2.6 days for RB whereas it was only 1.2 days for HRB. Furthermore, some immunomodulatory action was observed in laboratory tests. HRB was shown to be useful in reducing the physical stress associated with acute respiratory tract infection.