title: Does a single cup of caffeinated drink significantly increase blood pressure in young adults? A randomised controlled trial.
abstract: BACKGROUND
  Previous studies have shown that the blood pressure elevating effect of acute caffeine consumption was variable because of the heterogeneity of study participants, dosage of caffeine and study designs.
  
  
  OBJECTIVE
  This research aimed to examine the effect of a single cup of coffee on the blood pressure of young adults.
  
  
  METHODS
  Normotensive adults were randomised to receive either a cup of caffeinated drink (intervention group) or a cup of decaffeinated drink (control group). The main outcome measure was mean change in systolic blood pressure (SBP) and diastolic blood pressure (DBP) between intervention and control groups.
  
  
  RESULTS
  Enrolled participants (n = 104) were randomly assigned to the intervention group (n = 53) or the control group (n = 51). The mean differences in SBP and DBP of the two groups were +2.77 mmHg (P = 0.05) and +2.11 mmHg (P = 0.64), respectively. Therefore, the rise in both SBP and DBP after caffeine consumption was not statistically significant.
  
  
  CONCLUSIONS
  Our study confirmed that drinking a single cup of coffee (containing 80 mg of caffeine) does not have a significant impact on the blood pressure of healthy normotensive young adults one hour after the drink.
authors.affiliation: MBBS, MMed, FRACGP, is Professor, Department of Family Medicine, International Medical University, Negeri Sembilan, Malaysia.
authors.forename: Cheong Lieng
authors.initials: CL
authors.lastname: Teng
authors.forename: Wee Yang
authors.initials: WY
authors.lastname: Lim
authors.forename: Chen Zhi
authors.initials: CZ
authors.lastname: Chua
authors.forename: Richard Soon Kiat
authors.initials: RS
authors.lastname: Teo
authors.forename: Kenny Tze Hoe
authors.initials: KT
authors.lastname: Lin
authors.forename: Jie Cong
authors.initials: JC
authors.lastname: Yeo
mesh_terms: D001794:Blood Pressure / Q000187:drug effects*; D002110:Caffeine / Q000009:adverse effects*; D003069:Coffee / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D055815:Young Adult
chemical_list: D003069:Coffee; D002110:Caffeine