Home>News Center>Life
         
 

Smoking can lessen IQ, thinking ability: study
(Reuters)
Updated: 2005-10-25 06:22

The poorer mental function seen among alcoholics, many of whom also regularly smoke cigarettes, may be partially due to the long-term effects of nicotine, new research suggests.

"People who are also smokers are at a much higher risk," Dr. Jennifer M. Glass, of the University of Michigan's Addiction Research Center, told Reuters Health.

In her study, "cigarette smoking was negatively related to IQ and thinking," she said.

This finding may seem counterintuitive, since many smokers attest to feeling more alert and focused after smoking. Indeed, research shows that improved mental functioning is one of the immediate effects of nicotine exposure. Chronic smoking, however, is known to have the opposite effect.

Studies show that up to 87 percent of alcoholics smoke cigarettes, compared to less than 30 percent of the general United States population. Yet, few studies have looked into cigarette smoking as a factor that might explain the cognitive deficits reported among alcoholics.

To investigate that association, Glass and her colleagues examined brain function among 172 men from the same community, including 103 men who abused alcohol.

The team found that men with higher scores on the lifetime alcohol problems scale (LAPS) and those who reported a higher number of pack-years of smoking (i.e. packs of cigarettes smoked per day times number of years) both had lower IQ scores and lower scores on a test of global proficiency.

The proficiency test took into account the speed and accuracy with which the men were able to perform on a battery of tests including those that measured short-term memory, verbal reasoning and mathematical reasoning.

Upon further investigation, the researchers found that smoking predicted poorer global proficiency even more strongly than alcoholism did. Their findings were published online before publication in Drug and Alcohol Dependence.

Smoking also appeared to be independently associated with weaker verbal and visual-spatial reasoning, the study indicates.

Thus, though smoking did not account for all of the decreased neurocognitive functioning observed among the alcohol abusers, it did seem to account for some of the effects, the report indicates.

The reason for the observed associations is unknown, and the researchers did not investigate the "cause and effect story," Glass said, but she speculated that the diminished cognitive ability among smokers may be partly due to some mechanism involving a restricted flow of blood and oxygen to the brain.

Based on the current report, Glass said, "if you need another reason to quit smoking, it's a good potential one to add to the list."



Maggie calls for breast protection
New 'Harry Potter' movie may scare kids
Carina Lau hints at marriage
  Today's Top News     Top Life News
 

Bird flu: Beijing demands rapid response

 

   
 

President Hu to visit North Korea this week

 

   
 

Foreigners busted in illegal forex dealings

 

   
 

Law aims to keep unsafe food off the table

 

   
 

China pursues 'multi-faceted' diplomacy

 

   
 

China to blacklist, penalize polluting cities

 

   
  Nujiang dam project tests environmental policy
   
  'Dream come true' with director Zhang Yimou
   
  1/4 Chinese women dissatisfied with sex
   
  Scholars need money, time to get Nobel Prize
   
  Property bubble limited to some cities: official
   
  Rural Chinese pay price for ambition
   
 
  Go to Another Section  
 
 
  Story Tools  
   
  Feature  
  Could China's richest be the tax cheaters?  
Advertisement