BRAIN CHEMICAL MAY EXPLAIN ADDICTION TO FOOD, DRUGS

NEW YORK (Reuters Health) - People who become addicted to drugs and those
who eat compulsively may experience similar changes in brain chemistry that
keep them coming back for more, experts suggested here Tuesday.

This theory is just one put forth at a conference on the relationship
between substance abuse and eating disorders. While it is well known that
people who suffer from bulimia and anorexia nervosa are more likely to
abuse drugs, alcohol or nicotine, the reasons why remain unclear.

According to Dr. Alan I. Leshner, director of the National Institute of
Drug Abuse, one of the National Institutes of Health (NIH), the factors
that motivate a person to abuse drugs or eat compulsively may share
circuits in the brain.

For example, studies have shown that restricting food changes levels of
dopamine--a brain chemical associated with feelings of pleasure--in the
brains of mice. It is also known that cocaine makes a person's brain more
sensitive to heroin via changes in dopamine levels, Leshner said.

So, ``food restriction might sensitize the brain to drugs,'' he told
Reuters Health.

However, he stressed that far more research is needed into the relationship
between eating disorders and drug abuse and how to best treat people who
suffer from both.

``Researchers still do not know or fully understand all of the driving
forces behind the (co-occurrence) of eating disorders and substance
abuse,'' said Joseph A. Califano, Jr, president of the National Center on
Addiction and Substance Abuse at Columbia University in New York City, one
of the event's sponsors.

What is known is that people who have certain eating disorders are more
likely to smoke, drink and abuse drugs, he said. For example, students who
have dieted by the sixth grade are more than 20% more likely to drink
alcohol by the ninth grade. And the more frequently an incoming college
female diets, the more likely she is to use drugs and abuse alcohol,
Califano said.

Further, 12% to 18% of individuals with anorexia and 30% to 70% of people
with bulimia abuse tobacco, alcohol, pills and over-the-counter drugs.

Previous studies have shown that heavy smokers may use nicotine to manage
psychiatric problems including bulimia and binge eating. Nicotine,
according to one study, can quickly alter brain chemicals including
dopamine, and can either sedate or stimulate depending on the timing and
dosage of the drug.

And many women use smoking as a weight-control tool. Califano said girls
who smoke to suppress their appetites are among the largest group of new
nicotine addicts, and women who smoke are more than two-times as likely as
men to cite weight control as a reason not to quit smoking.

``The tobacco companies understood the relationship between smoking and
weight control long before the public health experts,'' Califano said,
describing a 1920s advertisement for Lucky Strike cigarettes that told
women to ``reach for a Lucky Strike instead of a sweet.''

The latest slogan for Capri cigarettes is ``there's no slimmer way to smoke.''

To be sure, the nature of the relationship is complex. Parents, peers,
media and genetic factors can all shape a young person's risk of developing
eating disorders and drug and alcohol problems, other panelists pointed out.

Steven Levenkron, a New York City-based therapist, said that while culture
and peers can influence an adolescent's behavior, parents play the most
important role.

``There is no question that relationships (with parents) are a major, major
issue in the development of a child's personality, emotional makeup and
chemical system,'' said Levenkron, who specializes in the treatment of
girls with anorexia.

``Kids incorporate and hear every single word. As parents and caretakers,
we mediate the culture,'' he said.

Recent studies support this view. According to one study, a parent's
influences predicted whether or not a youngster became ''highly concerned
with weight'' or ``a constant dieter'' regardless of the child's age and
weight.

Another study found that a parent's concern with a child's weight can hurt
the self-esteem of girls as young as age 5. Girls whose parents were the
most concerned about their child's weight perceived themselves to be the
least capable of physical activity. And girls whose mothers went so far as
to restrict their food intake expressed less confidence in their
intellectual ability and had lower self-esteem.

The conference was sponsored by the National Center on Addiction and
Substance Abuse (CASA) at Columbia University in New York City, the
National Institute on Drug Abuse, the National Institute of Mental Health
and the Commonwealth Fund.