Europe South Asia Asia Pacific Americas Middle East Africa BBC Homepage World Service Education



Front Page

World

UK

UK Politics

Business

Sci/Tech

Health

Education

Sport

Entertainment

Talking Point

In Depth

On Air

Archive
Feedback
Low Graphics
Help

Wednesday, July 7, 1999 Published at 18:15 GMT 19:15 UK


Health

Diet supplements could boost IQ

Dietary supplements may effect the working of the brain

Scientists have uncovered a new spin on the old adage you are what you eat.

They believe that changing the balance of chemicals in the brain by taking dietary supplements might boost intelligence.

Researchers have found a link between two brain chemicals and IQ.

Concentrations of the chemicals N-acetylaspartate (NAA) and choline are known to alter when people suffer brain diseases or injuries.

According to the new study, levels of the chemicals in healthy people account for much of the variation in people's IQ.

NAA is found only in neurons (nerve cells) and is thought to help them function properly, while choline is present in nerve cell membranes.

When large numbers of neurons are injured or killed, NAA levels drop and damaged cells release more choline.

In patients with brain injuries this shift is associated with a loss of thinking ability.

A study of 26 healthy volunteers with no history of brain disease or psychiatric illness showed a strong link between their performance in IQ tests and levels of the chemicals.

Low levels of choline and high levels of NAA were associated with high IQ.

Statistical analysis showed that the chemicals together could account for 45% of IQ variation.

Surprising finding

Neuroscientist William Brooks, of the University of New Mexico in Albuquerque, USA, who led the research, told New Scientist magazine: "We really didn't know what to expect, but we were surprised by what we found."

He speculated that in healthy people levels of NAA and choline reflected the rate at which neurons were being damaged and the amount of energy the brain was using to maintain them.

"If you have healthy neurons but you're struggling to keep them repaired, it makes sense you won't be as cognitively sound," he said.

However another possibility was that NAA and choline might directly enhance or inhibit the function of neurons.

If that was true, it might be possible to improve intellectual performance with dietary supplements, said Mr Brooks.

Howard Gardner, a psychologist at Harvard University, warned that IQ test performance could be affected by many factors, such as the subject's health and motivation.

"Beware the intelligence equals IQ equation," he said.

Mr Brooks hopes to examine more carefully what particular abilities NAA and choline most affect in a larger group of volunteers.



Advanced options | Search tips




Back to top | BBC News Home | BBC Homepage | ©


Health Contents

Background Briefings
Medical notes

Relevant Stories

20 May 99 | Health
The impact of depression on the brain

23 Mar 99 | Health
Bigger brains help hunt for mates

22 Mar 99 | Health
Sleep deprivation dangers

26 Nov 98 | Health
Premature babies need enriched diets

22 Oct 98 | Health
Cocaine kids have lower IQs

14 Oct 98 | Health
Boosting baby's IQ? It's all talk





Internet Links


Brain, a journal of neurology

New Scientist

Choline


The BBC is not responsible for the content of external internet sites.




In this section

Disability in depth

Spotlight: Bristol inquiry

Antibiotics: A fading wonder

Mental health: An overview

Alternative medicine: A growth industry

The meningitis files

Long-term care: A special report

Aids up close

From cradle to grave

NHS reforms: A guide

NHS Performance 1999

From Special Report
NHS in crisis: Special report

British Medical Association conference '99

Royal College of Nursing conference '99