title: The Role of Physical Activity in Harm Reduction among Betel Quid Chewers from a Prospective Cohort of 419,378 Individuals.
abstract: OBJECTIVE
  To assess the benefits of regular exercise in reducing harms associated with betel quid (BQ) chewing.
  
  
  METHODS
  The study cohort, 419,378 individuals, participated in a medical screening program between 1994 and 2008, with 38,324 male and 1,495 female chewers, who consumed 5-15 quids of BQ a day. Physical activity of each individual, based on "MET-hour/week", was classified as "inactive" or "active", where activity started from a daily 15 minutes/day or more of brisk walking (≥3.75 MET-hour/week). Hazard ratios for mortality and remaining years in life expectancy were calculated.
  
  
  RESULTS
  Nearly one fifth (18.7%) of men, but only 0.7% of women were chewers. Chewers had a 10-fold increase in oral cancer risk; and a 2-3-fold increase in mortality from lung, esophagus and liver cancer, cardiovascular disease, and diabetes, with doubling of all-cause mortality. More than half of chewers were physically inactive (59%). Physical activity was beneficial for chewers, with a reduction of all-cause mortality by 19%. Inactive chewers had their lifespan shortened by 6.3 years, compared to non-chewers, but being active, chewers improved their health by gaining 2.5 years. The improvement, however, fell short of offsetting the harms from chewing.
  
  
  CONCLUSIONS
  Chewers had serious health consequences, but being physically active, chewers could mitigate some of these adverse effects, and extend life expectancy by 2.5 years and reduce mortality by one fifth. Encouraging exercise, in addition to quitting chewing, remains the best advice for 1.5 million chewers in Taiwan.
authors.affiliation: Department of Leisure and Recreation Management, Asia University, Taichung, Taiwan.
authors.forename: Feng En
authors.initials: FE
authors.lastname: Lo
authors.affiliation: Institute of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan.
authors.forename: Po Jung
authors.initials: PJ
authors.lastname: Lu
authors.affiliation: Institute of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan.
authors.forename: Min Kuang
authors.initials: MK
authors.lastname: Tsai
authors.affiliation: Institute of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan.
authors.forename: June Han
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Radiological Sciences, University of California at Irvine, Irvine, CA, United States of America.
authors.forename: Christopher
authors.initials: C
authors.lastname: Wen
authors.affiliation: Institute of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan.|China Medical University Hospital, Taichung, Taiwan.
authors.forename: Chi Pang
authors.initials: CP
authors.lastname: Wen
authors.affiliation: Institute of Sport Science, National Taiwan Sport University, Taoyuan, Taiwan.
authors.forename: Jackson Pui Man
authors.initials: JP
authors.lastname: Wai
authors.affiliation: MJ Health Management Institution, Taipei, Taiwan.
authors.forename: Chwen Keng
authors.initials: CK
authors.lastname: Tsao
authors.affiliation: Institute of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan.
authors.forename: Po Huang
authors.initials: PH
authors.lastname: Chiang
authors.affiliation: Department of Public Health, Taipei Medical University, Taipei, Taiwan.
authors.forename: Shu Yu
authors.initials: SY
authors.lastname: Lyu
authors.affiliation: Taoyuan Innovation Institute of Technology, Taoyuan, Taiwan.
authors.forename: Ko Lu
authors.initials: KL
authors.lastname: Ma
authors.affiliation: Department of Education & Research, Taipei City Hospital, Taipei, Taiwan.
authors.forename: Ying-Chen
authors.initials: YC
authors.lastname: Chi
authors.affiliation: Department of Risk Management and Insurance, National Kaohsiung First University of Science and Technology, Kaohsiung, Taiwan.|Department of International Business, Asia University, Taichung, Taiwan.
authors.forename: Chu-Shiu
authors.initials: CS
authors.lastname: Li
authors.affiliation: Department of Risk Management and Insurance, Feng Chia University, Taichung, Taiwan.
authors.forename: Chwen-Chi
authors.initials: CC
authors.lastname: Liu
authors.affiliation: Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, United States of America.
authors.forename: Xifeng
authors.initials: X
authors.lastname: Wu
mesh_terms: D000328:Adult; D001114:Areca / Q000009:adverse effects*; D003920:Diabetes Mellitus / Q000139:chemically induced / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D008409:Mastication; D008875:Middle Aged; D009043:Motor Activity; D009369:Neoplasms / Q000139:chemically induced / Q000401:mortality; D031701:Piper / Q000009:adverse effects*; D011446:Prospective Studies; D012309:Risk-Taking; D013624:Taiwan