%0 Journal Article %T Effects of Pre-Schooler Lifestyle on the Circadian Rhythm of Secretory Immunoglobulin A %A Takaaki Miyake %A Yoshiharu Tanaka %A Haruka Kawabata %A Shinya Saito %A Megumi Oda %J Health %P 178-187 %@ 1949-5005 %D 2021 %I Scientific Research Publishing %R 10.4236/health.2021.132016 %X Assuming that secretory immunoglobulin A (s-IgA) in pre-schoolers is influenced by wake-up time, bedtime, sleeping duration and activity, the current study examined the influence of basic pre-schooler lifestyle on the circadian rhythm of s-IgA. We conducted a questionnaire survey on lifestyle and measured steps, heart rate and salivary s-IgA in 44 pre-schoolers aged 4 or 5 years old. Saliva was collected over 2 days at six time points: bedtime, upon waking up, upon arriving at nursery school, before lunch, after lunch and upon going home. To obtain relatively reliable s-IgA values, the s-IgA concentration/total protein concentration ratio (referred to as s-IgA/T.P.) was calculated. Relationship between the s-IgA/T.P. and heart rate, steps, wake-up time, bedtime and sleeping duration was then examined using PearsonĄ¯s correlation coefficient. Accordingly, pre-schooler lifestyle had the following effect on circadian rhythm of s-IgA: 1) s-IgA/T.P. values were higher upon waking up than at other measurement time points; 2) pre-schoolers with considerable physical activity had high s-IgA/T.P. at bedtime and upon waking up; and 3) pre-schoolers with long sleeping durations and early bedtime had high s-IgA/T.P. upon waking up. Thus, our results confirmed that pre-schoolersĄ¯ lifestyle habits, such as bedtime, sleeping duration, physical activity, had an effect on the circadian rhythm of s-IgA. %K Pre-Schooler %K s-IgA %K Lifestyle %K Activity %K Sleep %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=107503