Ifølge et nyt studie fra University of Pennsylvania udgivet i sidste uge i tidsskriftet Scientific Reports, så sover børn, som spiser fisk mindst en gang om ugen, bedre og har IQ scorer som er 4.8 point højere i gennemsnit i sammenligning med dem som spiser fisk mindre ofte eller overhovedet ikke.

Tidligere studier har vist en forbindelse mellem omega-3, fedtsyrerne i mange typer fisk, og en forbedret intelligence, såvel som en forbindelse mellem omega-3s og bedre søvn. Men de er aldrig tidligere blevet forbundet. Dette arbejde, udført af Jianghong Liu, Jennifer Pinto-Martin og Alexandra Hanlon fra the School of Nursing og professor ved 'Penn Integrates Knowledge, Adrian Raine, afslører at søvn kunne muligvis være den manglende forbindelse mellem indtagelse af fisk og så intelligens.

Kommentar: Denne artikel er delvis oversat til dansk af fra: Omega-3s and the Brain: Fish Intake Linked to Higher IQ and Better Sleep

For the study, a cohort of 541 9- to 11-year-olds in China, 54 percent boys and 46 percent girls, completed a questionnaire about how often they consumed fish in the past month, with options ranging from "never" to "at least once per week." They also took the Chinese version of an IQ test called the Wechsler Intelligence Scale for Children-Revised, which examines verbal and non-verbal skills such as vocabulary and coding.

"Lack of sleep is associated with antisocial behavior; poor cognition is associated with antisocial behavior," said Raine. "We have found that omega-3 supplements reduce antisocial behavior, so it's not too surprising that fish is behind this."

Professor Adrian Raine is also author of the book The Anatomy of Violence - The Biological Roots of Crime where he argues that omega-3s are crucial to the brain. He summarizes various studies of these fatty acids and their role in antisocial behavior. For instance, a study of 11,875 pregnant women from Bristol, England, showed that offspring of mothers who did not eat much fish during pregnancy had more antisocial behavior.

In the United States, a study of 3,581 people from Chicago, Minneapolis, and Birmingham, Alabama, showed that those who hardly ever ate fish had higher levels of hostility than those eating fish at least once a week. There are also more behavior problems and temper tantrums in boys with lower total fatty-acid concentrations as measured from blood. Even dogs with low levels of omega-3s have been shown to be more aggressive.

Omega 3s have two important components: DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid). As Raine explains in his book:
What does DHA do? It is known to play a key role in neuronal structure and function. Making up 6 percent of the dry cerebral cortex, it influences the functioning of the blood-brain barrier that regulates what gets into your brain from your bloodstream. It enhances synaptic functioning, facilitating communication between brain cells. It makes up 30% of the membrane of your brain cell and regulates the activity of membrane enzymes. It protects the neuron from cell death. It increases the size of the cell.

DHA also stimulates neurite growth. There is more intricate dendritic branching in the neurons of animals fed a diet rich in omega-3 compared with those fed a normal diet. Dendrites of the cell receive signals from other brain cells, so this dendritic branching translates to more connectedness between cells. The axon that transmits the electrical signal to other cells is longer and has a better sheath to conduct the electrical impulse. DHA regulates serotonin and dopamine neurotransmitters, and we saw in chapter 2 that offenders have abnormalities in those neurotransmitters. We also know that DHA is involved in regulating gene expression, so in theory it can help turn on genes that protect against violence- or turn off genes that increase the probability of violence.

We also saw earlier that cognitive functioning is impaired in offenders. Omega-3 supplementation has been shown to improve learning and memory in animals, and also improves learning in children. So it's not just that omega-3s in theory improves the brain. In practice, it makes a difference in terms of cognitive functioning - and cognitive functioning is critical for performance in school and success in life.

Omega - 3 enhances both the brain structure and function...

The half-life of omega-3 in the body could be about two years - it stays in the body ready for re-uptake and it can make a lasting change in the brain. Improving brain structure and function omega-3 could help reduce violence in the long-term.
Raine also summarizes several studies that have shown that Omega-3s are linked with a reduction of serious offending within prison inmates. Omega-3s are also linked with reduced externalizing behavior problems in juveniles with bipolar disorder, and they reduce aggressive behavior in general as well. ADHD children have a reduction of oppositional defiant behavior after only fifteen weeks of omega-3. And women with borderline personalty disorder showed a reduction in aggression after 2 months of EPA supplementation. Studies have been found a nearly 43% reduction in conduct-disorder problems in children supplementing omega 3s.

Don't miss Raine's The Anatomy of Violence - The Biological Roots of Crime for a treasure trove of studies and other fascinating facts of the brain and its role in behavior.

Fishy Option

Omega-3 supplements have fallen out of favor in some circles because they get easily damaged (oxidized) with exposure to oxygen. If they get damaged, they go rancid. And if they go rancid, chances are that they will wreak havoc in your body, including DNA damage. Rancid fats not only mutate DNA directly, they also make DNA more susceptible to mutations induced by other environmental pollutants.

Furthermore, if the manufacturer doesn't guarantee quality control, it probably is oxidized. According to research quoted by Dr. Shanahan, "Even oil stored in the dark at 4 degrees Centigrade may oxidize unacceptably within a month of storage."

So what do we make of all the great studies on Omega-3 supplementation? Do we supplement or not?

Probably Rhonda Patrick, an American biochemist, has the answer for this one. Omega-3s are her favorite supplements, and she argues that they are good as long as they are kept fresh. She explains that there are manufacturers who utilize a nitrogen environment to eliminate the oxygen exposure during the fish oil processing, thereby maintaining the integrity of these vulnerable oils. She also recommends to keep Omega-3s in the refrigerator.

Let's keep in mind that animal saturated fat also protects the more vulnerable omega-3s - from damage and rancidity. And when supplement quality cannot be guaranteed, these fatty acids are best consumed when coming from fresh food sources (i.e. fish oil from fresh fish sources).

As research shows, Omega-3 enhances brain structure and function by increasing dendritic branching, enhancing synaptic functioning, boosting cell size, protecting the neuron from cell death, and regulating both neurotransmitter functioning and gene expression. May we all benefit from that!