In addition to helping protect us from heart disease
and cancer, a balanced diet and regular exercise can
also protect the brain and ward off mental disorders.
"Food is like a pharmaceutical compound that affects
the brain," said Fernando Gómez-Pinilla,
a UCLA professor of neurosurgery and physiological science
who has spent years studying the effects of food, exercise
and sleep on the brain. "Diet, exercise and sleep
have the potential to alter our brain health and mental
function. This raises the exciting possibility that
changes in diet are a viable strategy for enhancing
cognitive abilities, protecting the brain from damage
and counteracting the effects of aging."
Gómez-Pinilla analyzed more than 160 studies
about food's affect on the brain; the results of his
analysis appear in the July issue of the journal Nature
Reviews Neuroscience and are available online at www.nature.com/nrn/journal/v9/n7/abs/nrn2421.html.
fatty acids found in salmon, walnuts and
kiwi fruit provide many benefits, including improving
learning and memory and helping to fight against such
mental disorders as depression and mood disorders, schizophrenia,
and dementia, said Gómez-Pinilla, a member of
UCLA's Brain Research Institute and Brain Injury Research
Synapses in the brain connect neurons and provide critical
functions; much learning and memory occurs at the synapses,
"Omega-3 fatty acids support synaptic plasticity
and seem to positively affect the expression of several
molecules related to learning and memory that are found
on synapses," Gómez-Pinilla said. "Omega-3
fatty acids are essential for normal brain function.
"Dietary deficiency of omega-3 fatty acids in
humans has been associated with increased risk of several
mental disorders, including attention-deficit disorder,
dyslexia, dementia, depression, bipolar disorder and
schizophrenia," he said. "A deficiency of
omega-3 fatty acids in rodents results in impaired learning
Children who had increased amounts of omega-3 fatty
acids performed better in school, in reading and in
spelling and had fewer behavioral problems, he said.
Preliminary results from a study in England show that
school performance improved among a group of students
receiving omega-3 fatty acids. In an Australian study,
396 children between the ages 6 and 12 who were given
a drink with omega-3 fatty acids and other nutrients
(iron, zinc, folic acid and vitamins A, B6, B12 and
C) showed higher scores on tests measuring verbal intelligence
and learning and memory after six months and one year
than a control group of students who did not receive
the nutritional drink. This study was also conducted
with 394 children in Indonesia. The results showed higher
test scores for boys and girls in Australia, but only
for girls in Indonesia.
Getting omega-3 fatty acids from food rather than from
capsule supplements can be more beneficial, providing
additional nutrients, Gómez-Pinilla said.
Scientists are learning which omega-3 fatty acids seem
to be especially important. One is docosahexaenoic acid,
or DHA, which is abundant in salmon. DHA, which reduces
oxidative stress and enhances synaptic plasticity and
learning and memory, is the most abundant omega-3 fatty
acid in cell membranes in the brain.
"The brain and the body are deficient in the machinery
to make DHA; it has to come through our diet,"
said Gómez-Pinilla, who was born and raised in
salmon-rich Chile and eats salmon three times a week,
along with a balanced diet. "Omega-3 fatty acids
A healthy diet and exercise can also reduce the effect
of brain injury and lead to a better recovery, he said.
Recent research also supports the hypothesis that health
can be passed down through generations, and a number
of innovative studies point to the possibility that
the effects of diet on mental health can be transmitted
across generations, Gómez-Pinilla said.
A long-term study that included more than 100 years
of birth, death, health and genealogical records for
300 Swedish families in an isolated village showed that
an individual's risk for diabetes and early death increased
if his or her paternal grandparents grew up in times
of food abundance rather than food shortage.
"Evidence indicates that what you eat can affect
your grandchildren's brain molecules and synapses,"
Gómez-Pinilla said. "We are trying to find
the molecular basis to explain this."
Controlled meal-skipping or intermittent caloric restriction
might provide health benefits, he said.
Excess calories can reduce the flexibility of synapses
and increase the vulnerability of cells to damage by
causing the formation of free radicals. Moderate caloric
restriction could protect the brain by reducing oxidative
damage to cellular proteins, lipids and nucleic acids,
The brain is highly susceptible to oxidative damage.
Blueberries have been shown to have a strong antioxidant
capacity, he noted.
In contrast to the healthy effects of diets that are
rich in omega-3 fatty acids, diets high in trans fats
and saturated fats adversely affect cognition, studies
Junk food and fast food negatively affect the brain's
synapses, said Gómez-Pinilla, who eats fast food
less often since conducting this research. Brain synapses
and several molecules related to learning and memory
are adversely affected by unhealthy diets, he said.
Emerging research indicates that the effects of diet
on the brain, combined with the effects of exercise
and a good night's sleep, can strengthen synapses and
provide other cognitive benefits, he added.
In Okinawa, an island in Japan where people frequently
eat fish and exercise, the lifespan is one of the world's
longest, and the population has a very low rate of mental
disorders, Gómez-Pinilla noted.
Folic acid is found in various foods, including spinach,
orange juice and yeast. Adequate levels of folic acid
are essential for brain function, and folate deficiency
can lead to neurological disorders such as depression
and cognitive impairment. Folate supplementation, either
by itself or in conjunction with other B vitamins, has
been shown to be effective in preventing cognitive decline
and dementia during aging and enhancing the effects
of antidepressants. The results of a recent randomized
clinical trial indicate that a three-year folic acid
supplementation can help reduce the age-related decline
in cognitive function.
In patients with major depression and schizophrenia,
levels of a signaling molecule known as brain-derived
neurotrophic factor, or BDNF, are reduced. Antidepressants
elevate BDNF levels, and most treatments for depression
and schizophrenia stimulate BDNF. Here, too, omega-3
fatty acids are beneficial, as is the curry spice curcumin,
which has been shown to reduce memory deficits in animal
models of Alzheimer's disease and brain trauma. BDNF
is most abundant in the hippocampus and the hypothalamus
brain areas associated with cognitive and metabolic
The high consumption of curcumin in India may contribute
to the low prevalence of Alzheimer's disease on the
In humans, a mutation in a BDNF receptor has been linked
to obesity and impairments in learning and memory.
"BDNF is reduced in the hippocampus, in various
cortical areas and in the serum of patients with schizophrenia,"
Gómez-Pinilla said. "BDNF levels are reduced
in the plasma of patients with major depression."
Smaller food portions with the appropriate nutrients
seem to be beneficial for the brain's molecules, such
as BDNF, he said.
Gómez-Pinilla showed in 1995 that exercise can
have an effect on the brain by elevating levels of BDNF.
He noted that while some people have extremely good
genes, most of us are not so lucky and need a balanced
diet, regular exercise and a good night's sleep.