Smoking harms your brain as well as your body: It leads to sharp decline in mental ability, warns study Test on nearly 9,000 people over 50 have shown lifestyles could damage the mind as well as the bodySmoking, high blood pressure, high cholesterol levels and a high BMI all worsen the risk
00:30 GMT, 27 November 2012
Tests on 8,800 people over 50 have showed cigarettes can damage memory
Smoking is known to be highly damaging to physical health, being a major factor in cancer and heart disease.
Now, however, its alarming effects on the mental well-being of millions of smokers have been outlined by British scientists.
Lighting up regularly has been associated with a sharp decline in the performance of the brain, according to their study.
They found that middle-aged smokers performed less well on tests compared with those without the tobacco habit.
The project examined memory, planning
and overall mental ability after four and eight years. The tests
included asking people to learn new words or name as many animals as
they could in a minute.
Researchers concluded that smoking ‘consistently’ reduced all three performance measures after four years.
They also found that high blood pressure and being overweight took their toll of brainpower – but not as much as smoking.
The team warned that people need to be aware of the impact on their health of lifestyle choices, like smoking.
Risk factor data was examined for more
than 8,800 people aged 50 and over taking part in the English
Longitudinal Study of Ageing.
The researchers at King’s College
London were investigating links between the likelihood of a heart attack
or stroke and the state of the brain.
Smoking, high blood pressure, high cholesterol levels and a high BMI all worsen the risk of dementia
High blood pressure and high risk of
stroke were also associated with lower scores for memory and overall
mental ability after eight years.
Being overweight was linked to poor
memory, according to the findings published in the journal Age and
Ageing. Lead scientist Dr Alex Dregan said ‘Cognitive decline becomes
more common with ageing and, for an increasing number of people,
interferes with daily functioning and well-being.
‘We have identified a number of risk
factors which could be associated with accelerated cognitive decline,
all of which could be modifiable. This offers valuable knowledge for
prevention and treatment interventions.’
The researchers said their results indicate that high blood pressure has a gradual effect on the brain over a long period.
This could explain why short-term
trials of blood pressure drugs being used to treat mental decline failed
to show a clear benefit.
Recent laboratory research suggested a
compound in tobacco called NNK provokes white blood cells in the
central nervous system to attack healthy cells, leading to severe
neurological damage. There are almost 10 million smokers in the UK. The
habit is still by far the biggest single cause of preventable illness
and premature death.
It is a major contributory factor in causing heart disease and 39,000 lung cancer cases each year.
Dr Simon Ridley, of Alzheimer’s
Research UK, said: ‘Research has repeatedly linked smoking and high
blood pressure to a greater risk of cognitive decline and dementia. This
study adds weight to that.
‘Cognitive decline as we age can
develop into dementia, and unravelling the factors linked to this
decline could be crucial for finding ways to prevent the condition.’
Jessica Smith, of the Alzheimer’s
Society, said: ‘We all know smoking, a high blood pressure, high
cholesterol and a high Body Mass Index is bad for our heart.
‘This adds to the huge amount of evidence that also suggests they can be bad for our head too.’
One in three of the over-65s will develop dementia, she added.