Ped Med: The skinny on ADHD contributors

By LIDIA WASOWICZ
UPI Senior Science Writer

SAN FRANCISCO, March 17 (UPI) -- Nutritionists are convinced that,
just like everyone else, children with attention-deficit/hyperactivity
disorder are what they eat.

Specifically, the specialists have their eye on so-called omega-3
fatty acids as playing some role in the condition that, in general, is
marked by trouble keeping still, difficulty in maintaining attention,
propensity toward acting impulsively or some combination of the three.

Omega-3 fatty acids are plentiful in cold-water fish, such as salmon,
herring, tuna, clams, crab, cod, flounder, sole, halibut, catfish,
trout and shrimp. They also abound in nuts; soybeans; walnut, olive
and flaxseed oil; seeds; whole grains and dark leafy greens.

The fatty acids comprise a hefty component of the brain, which weighs
in at about 60-percent fat.

The compounds, which studies indicate are essential for forming and
maintaining the dopamine system, have been found in short supply in
some, though not all, children diagnosed with ADHD.

Many researchers see ADHD as a hereditary imbalance of brain
chemicals, such as dopamine -- which regulates movement, emotion,
motivation and sensations of pleasure.

That view is strongly contested by critics who point to a dearth of
physical evidence for such a notion.

Whatever their connection to the "feel-good" chemical in the brain,
the omega-3 fatty acids appear to have an impact on a child's
behavior, portending problems in youngsters who don't have enough of
the compounds.

As one example, a recent Duke University study of 96 boys ages 6 to 12
indicated those with low blood levels of omega-3 fatty acids face
increased risk of ADHD-like behavior, learning and health challenges.

There is also some evidence the compounds may play a benevolent role
in the production of myelin, a protective insulation that coats the
brain's internal wiring,

A novel model of human brain development and degeneration proposed by
researchers at the University of California, Los Angeles implicates
disruption of myelin production in such childhood developmental
disorders as autism and ADHD.

From a review of scanned and autopsied brain tissue, the investigators
unraveled the role of myelin in these conditions.

Laden with more cholesterol than any other brain component, the sheet
of fat surrounds the spindly nerve-cell extensions called axons,
permitting them to carry messages to their neighbors in the safety and
security of their armor.

The thicker and heavier the cells' coat, the faster and more effective
their communication, said team leader Dr. George Bartzokis, professor
of neurology at the David Geffen School of Medicine and director of
the UCLA Memory Disorders and Alzheimer's Disease Clinic and the
Clinical Core of the UCLA Alzheimer's Disease Research Center.

The pioneering neuroscientist discovered that myelin production
continues unabated throughout the first four decades of life before
peaking and plummeting at age 45. His latest research portrays the
protective shield as the neural system's Achilles' heel, vulnerable to
a host of environmental assaults.

"Myelination, a process uniquely elaborated in humans, arguably is the
most important and most vulnerable process of brain development as we
mature and age," Bartzokis said.

Without adequate insulation, cells won't connect properly, he has
found in a series of experiments that showed a breakdown in the sheath
can expose the naked wiring beneath and open the gates to an array of
neurological and behavioral problems.

Bartzokis's theory holds that humans "myelinate" different circuits at
various points in life, which could explain the sizeable differences
between brain diseases of the young and old.

An early disruption of the process, for instance, may throw for a loop
the development of the basic circuits that govern language and social
communication, two key impairments in autism.

A glitch during the early school years could hamper the ability to
process information efficiently and effectively, leading to deficits
in attention that characterize ADHD. Later in life, the result of a
malfunction could be Alzheimer's disease.

To Bartzokis, the human brain is akin to high-speed Internet.

"The speed, quality and bandwidth of the connections determine the
brain's ability to process information, and all these depend in large
part on the insulation that coats the brain's connecting wires," he said.

The findings may explain why developmental disorders leave no calling
card in the brain. "There's no dead anything on autopsy," Bartzokis
said. "Those brain connections just never developed normally."

Bartzokis's studies also show female brains make better myelin, which
could explain why boys are at much greater risk for autism, ADHD and
other problems.

"On the positive side, there are some interesting things to consider,"
Bartzokis said. "For example, essential fatty acids are fats that are
necessary for membrane production, and myelin is essentially pure
membrane."

"They are called 'essential' because the human body cannot produce
them, and, therefore, they are like 'vitamins' -- they need to come
from a good diet," he added. "Thus, nutrition is very important
because the brain is very busy trying to build the myelin sheaths."

Still, researchers don't have the skinny on the exact relationship
between the fats and ADHD.

Although alternative medicine practitioners report some success in
ameliorating symptoms with the use of fatty acid, mineral, vitamin B
and other supplements, none of these has been embraced as standard
therapy.

Conventional and complementary practices also part ways on the role,
and remedial potential, of food additives, sugar or allergens. All of
these remain controversial, having failed to withstand rigorous
scientific scrutiny, according to a compilation of ADHD data by Dr.
Peter Jensen, director of the Center for the Advancement of Children's
Mental Health at Columbia University.

Next: Seeking environmental clues to ADHD.

(Editors' Note: This series on ADHD is based on a review of hundreds
of reports and a survey of more than 200 specialists.)

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