Abstract
The effects of alcohol consumption on health are suggested to depend on the amount of alcohol consumed. We investigated the objective and subjective health effects of the daily consumption of a small amount of alcohol in healthy individuals using a randomized, double-blind, placebo-controlled crossover study. Accordingly, 15 male and 27 female Japanese adults with average or lower general well-being schedule (GWBS) scores were asked to consume a beverage with 0.5% (v/v) alcohol (~4 g of alcohol a day; test beverage) and a placebo beverage two times daily for 4 weeks each. Regular low-level alcohol consumption significantly decreased the serum liver function indexes (aspartic aminotransferase, alanine aminotransferase, and lactate dehydrogenase) before and after consumption (p = 0.034, 0.033, and 0.013, respectively). The small amount of alcohol did not affect the participants' GWBS scores; however, a stratified analysis with poor subjective well-being revealed that these changes differed significantly between low-level alcohol consumption and placebo-treated subjects (16.0 vs. 11.5, p = 0.041). In addition, changes in serum testosterone levels demonstrated a higher trend in the group that received the test beverage compared with the group that received the placebo beverage (p = 0.051). Daily low-level alcohol consumption may have positive effects on liver function and subjective well-being.