In Japan there are many people who are intolerant to alcohol. Known as flushers, they do not genetically have low Km acetaldehyde dehydrogenase (AlDH₂). Flushers are judged easily and accurately by the alcohol patch test. An ethanol patch test carried out on agricultural and fishing populations in Japan showed that approx. 40% were deficient in AlDH₂. A questionnaire survey of the drinking behavior of many people showed significant differences between the normal AlDH₂ and AlDH₂-deficient groups. The normal group drinks positively and actively, while the deficient group drinks negatively and passively. As a result, there were significant differences in subjective and objective symptoms that result from drinking between the two groups: More frequent hangovers, abnormal physical conditions and higher KAST scores were seen in the normal group, and health examination showed higher values in liver function tests, including γ-GTP, and higher levels of blood pressure, HDL-cholesterol (HDL-C), etc., in the normal AlDH₂group.
It may be very useful for prevention of alcohol-related health disorders to help Mongoloid peoples, such as the Japanese, recognize whether their AlDH₂ is normal or deficient, which is as determined by the ethanol patch test.