Featured Research

from universities, journals, and other organizations

Smoking takes 10 years off life expectancy in Japan, not 4 as previously thought, experts warn

Date:
October 26, 2012
Source:
BMJ-British Medical Journal
Summary:
Smoking reduces life expectancy by ten years in Japan, but much of the risk can be avoided by giving up smoking, a new paper shows.

Smoking reduces life expectancy by ten years in Japan, but much of the risk can be avoided by giving up smoking, a paper published on bmj.com shows.

Previous studies in Japan suggested smoking reduced life expectancy by only a few years compared with about ten years in Britain and the USA. This new report, from researchers in Oxford and Japan, investigates the impact of smoking on mortality in a large group of Japanese people who were living in Hiroshima or Nagasaki in 1950. The findings are, however, nothing to do with radiation exposure from the bombs.

The Life Span Study (LSS) was initiated in 1950 to investigate the effects of radiation, tracking over 100,000 people. However, most received minimal radiation exposure, and can therefore provide useful information about other risk factors. Surveys carried out later obtained smoking information for 68,000 men and women, who have now been followed for an average of 23 years to relate smoking habits to survival.

The younger a person was when they started smoking the higher the risk in later life. Older generations did not usually start to smoke until well into adult life, and usually smoked only a few cigarettes per day. In contrast, Japanese born more recently (1920-45) usually started to smoke in early adult life, much as smokers in Britain and the USA.

These differences in smoking habits are reflected in the mortality patterns. Smokers born before 1920 lost just a few years. In contrast, men born later (1920-45) who started to smoke before age 20 lost nearly a decade of life expectancy, and had more than double the death rate of lifelong non-smokers, suggesting that more than half of these smokers will eventually die from their habit. Results on the few women who had smoked since before age 20 were similar.

Previous studies of the effects of smoking in Japan had been mainly of individuals born in the first few decades of the twentieth century who probably didn't start to smoke until well into adult life and smoked only a few cigarettes per day. This explains why the risks of smoking seemed low. Nowadays, however, young Japanese smokers tend to smoke more cigarettes per day and to start at a younger age, so their risks will be higher.

In addition to studying the risk of smoking, the researchers were able to examine the benefits of stopping. As elsewhere, those who stopped smoking before age 35 avoided almost all the excess risk among continuing smokers, and even those who stopped around age 40 avoided most of it.

The researchers conclude that the future health risks to young smokers are likely to be just as big in Japan as in other countries although much of the risk can be avoided by stopping.


Story Source:

The above story is based on materials provided by BMJ-British Medical Journal. Note: Materials may be edited for content and length.


Journal Reference:

  1. R. Sakata, P. McGale, E. J. Grant, K. Ozasa, R. Peto, S. C. Darby. Impact of smoking on mortality and life expectancy in Japanese smokers: a prospective cohort study. BMJ, 2012; 345 (oct25 2): e7093 DOI: 10.1136/bmj.e7093

Cite This Page:

BMJ-British Medical Journal. "Smoking takes 10 years off life expectancy in Japan, not 4 as previously thought, experts warn." ScienceDaily. ScienceDaily, 26 October 2012. <www.sciencedaily.com/releases/2012/10/121025193646.htm>.
BMJ-British Medical Journal. (2012, October 26). Smoking takes 10 years off life expectancy in Japan, not 4 as previously thought, experts warn. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2012/10/121025193646.htm
BMJ-British Medical Journal. "Smoking takes 10 years off life expectancy in Japan, not 4 as previously thought, experts warn." ScienceDaily. www.sciencedaily.com/releases/2012/10/121025193646.htm (accessed October 23, 2014).

Share This



More Health & Medicine News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) Is your child ready? Video provided by Working Mother
Powered by NewsLook.com
U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

Newsy (Oct. 22, 2014) Now that the U.S. is restricting travel from West Africa, some are dropping questions about a travel ban and instead asking about visa bans. Video provided by Newsy
Powered by NewsLook.com
US to Track Everyone Coming from Ebola Nations

US to Track Everyone Coming from Ebola Nations

AP (Oct. 22, 2014) Stepping up their vigilance against Ebola, federal authorities said Wednesday that everyone traveling into the US from Ebola-stricken nations will be monitored for symptoms for 21 days. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Doctors Help Paralysed Man Walk Again, Patient in Disbelief

Doctors Help Paralysed Man Walk Again, Patient in Disbelief

AFP (Oct. 22, 2014) Polish doctors describe how they helped a paralysed man walk again, with the patient in disbelief at the return of sensation to his legs. Duration: 1:04 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins