Wednesday, October 18, 2006

The Most Fascinating Science News of the Week, The Month--Maybe The Year

The New Jersey Coalition for Self-Defense blog linked to this absolutely fascinating and clearly relevant piece of scientific research about diet and violence--and if the research can be confirmed, suggests a way to substantially reduce violence--although unfortunately, opening up a never-ending string of lawsuits by the ambulance chasers. The article in the Guardian:
Demar has been in and out of prison so many times he has lost count of his convictions. "Being drunk, being disorderly, trespass, assault and battery; you name it, I did it. How many times I been in jail? I don't know, I was locked up so much it was my second home."

Demar has been taking part in a clinical trial at the US government's National Institutes for Health, near Washington. The study is investigating the effects of omega-3 fatty acid supplements on the brain, and the pills that have effected Demar's "miracle" are doses of fish oil.

The results emerging from this study are at the cutting edge of the debate on crime and punishment. In Britain we lock up more people than ever before. Nearly 80,000 people are now in our prisons, which reached their capacity this week.

But the new research calls into question the very basis of criminal justice and the notion of culpability. It suggests that individuals may not always be responsible for their aggression. Taken together with a study in a high-security prison for young offenders in the UK, it shows that violent behaviour may be attributable at least in part to nutritional deficiencies.

The UK prison trial at Aylesbury jail showed that when young men there were fed multivitamins, minerals and essential fatty acids, the number of violent offences they committed in the prison fell by 37%. Although no one is suggesting that poor diet alone can account for complex social problems, the former chief inspector of prisons Lord Ramsbotham says that he is now "absolutely convinced that there is a direct link between diet and antisocial behaviour, both that bad diet causes bad behaviour and that good diet prevents it."

The Dutch government is currently conducting a large trial to see if nutritional supplements have the same effect on its prison population. And this week, new claims were made that fish oil had improved behaviour and reduced aggression among children with some of the most severe behavioural difficulties in the UK.
The scientist at the National Institute of Health running this study explains why he thinks this dietary change makes a difference:
His hypothesis is that modern industrialised diets may be changing the very architecture and functioning of the brain.

We are suffering, he believes, from widespread diseases of deficiency. Just as vitamin C deficiency causes scurvy, deficiency in the essential fats the brain needs and the nutrients needed to metabolise those fats is causing of a host of mental problems from depression to aggression. Not all experts agree, but if he is right, the consequences are as serious as they could be. The pandemic of violence in western societies may be related to what we eat or fail to eat. Junk food may not only be making us sick, but mad and bad too.

...

The researchers at the National Institute on Alcohol Abuse and Alcoholism, which is part of NIH, had placed adverts for aggressive alcoholics in the Washington Post in 2001. Some 80 volunteers came forward and have since been enrolled in the double blind study. They have ranged from homeless people to a teacher to a former secret service agent. Following a period of three weeks' detoxification on a locked ward, half were randomly assigned to 2 grams per day of the omega-3 fatty acids EPA and DHA for three months, and half to placebos of fish-flavoured corn oil.

An earlier pilot study on 30 patients with violent records found that those given omega-3 supplements had their anger reduced by one-third, measured by standard scales of hostility and irritability, regardless of whether they were relapsing and drinking again. The bigger trial is nearly complete now and Dell Wright, the nurse administering the pills, has seen startling changes in those on the fish oil rather than the placebo. "When Demar came in there was always an undercurrent of aggression in his behaviour. Once he was on the supplements he took on the ability not to be impulsive. He kept saying, 'This is not like me'."

Demar has been out of trouble and sober for a year now. He has a girlfriend, his own door key, and was made employee of the month at his company recently. Others on the trial also have long histories of violence but with omega-3 fatty acids have been able for the first time to control their anger and aggression. J, for example, arrived drinking a gallon of rum a day and had 28 scars on his hand from punching other people. Now he is calm and his cravings have gone. W was a 19st barrel of a man with convictions for assault and battery. He improved dramatically on the fish oil and later told doctors that for the first time since the age of five he had managed to go three months without punching anyone in the head.
Now, this doesn't seem to be case for everyone. I wonder if it might be something where some people are simply not able to handle the shortage of omega-3 as well as others. For example, the article explains that kids without behavioral problems don't seem to get much benefit from omega-3 rich diets. But if a small percentage of our population has a serious inability to control rage because of a dietary problem, that's something that can be fixed. It might also explain why the 20th century saw a rather impressive increase in violence in the U.S.:
Over the last century most western countries have undergone a dramatic shift in the composition of their diets in which the omega-3 fatty acids that are essential to the brain have been flooded out by competing omega-6 fatty acids, mainly from industrial oils such as soya, corn, and sunflower. In the US, for example, soya oil accounted for only 0.02% of all calories available in 1909, but by 2000 it accounted for 20%. Americans have gone from eating a fraction of an ounce of soya oil a year to downing 25lbs (11.3kg) per person per year in that period. In the UK, omega-6 fats from oils such as soya, corn, and sunflower accounted for 1% of energy supply in the early 1960s, but by 2000 they were nearly 5%. These omega-6 fatty acids come mainly from industrial frying for takeaways, ready meals and snack foods such as crisps, chips, biscuits, ice-creams and from margarine. Alcohol, meanwhile, depletes omega-3s from the brain.

To test the hypothesis, Hibbeln and his colleagues have mapped the growth in consumption of omega-6 fatty acids from seed oils in 38 countries since the 1960s against the rise in murder rates over the same period. In all cases there is an unnerving match. As omega-6 goes up, so do homicides in a linear progression. Industrial societies where omega-3 consumption has remained high and omega-6 low because people eat fish, such as Japan, have low rates of murder and depression.

Of course, all these graphs prove is that there is a striking correlation between violence and omega 6-fatty acids in the diet. They don't prove that high omega-6 and low omega-3 fat consumption actually causes violence. Moreover, many other things have changed in the last century and been blamed for rising violence - exposure to violence in the media, the breakdown of the family unit and increased consumption of sugar, to take a few examples. But some of the trends you might expect to be linked to increased violence - such as availability of firearms and alcohol, or urbanisation - do not in fact reliably predict a rise in murder across countries, according to Hibbeln.
There's a detailed technical explanation as well:
Essential fatty acids are called essential because humans cannot make them but must obtain them from the diet. The brain is a fatty organ - it's 60% fat by dry weight, and the essential fatty acids are what make part of its structure, making up 20% of the nerve cells' membranes. The synapses, or junctions where nerve cells connect with other nerve cells, contain even higher concentrations of essential fatty acids - being made of about 60% of the omega-3 fatty acid DHA.

Communication between the nerve cells depends on neurotransmitters, such as serotonin and dopamine, docking with receptors in the nerve cell membrane.

Omega-3 DHA is very long and highly flexible. When it is incorporated into the nerve cell membrane it helps make the membrane itself elastic and fluid so that signals pass through it efficiently. But if the wrong fatty acids are incorporated into the membrane, the neurotransmitters can't dock properly. We know from many other studies what happens when the neurotransmitter systems don't work efficiently. Low serotonin levels are known to predict an increased risk of suicide, depression and violent and impulsive behaviour. And dopamine is what controls the reward processes in the brain.

Laboratory tests at NIH have shown that the composition of tissue and in particular of the nerve cell membrane of people in the US is different from that of the Japanese, who eat a diet rich in omega-3 fatty acids from fish. Americans have cell membranes higher in the less flexible omega-6 fatty acids, which appear to have displaced the elastic omega-3 fatty acids found in Japanese nerve cells.

Hibbeln's theory is that because the omega-6 fatty acids compete with the omega-3 fatty acids for the same metabolic pathways, when omega-6 dominates in the diet, we can't convert the omega-3s to DHA and EPA, the longer chain versions we need for the brain. What seems to happen then is that the brain picks up a more rigid omega-6 fatty acid DPA instead of DHA to build the cell membranes - and they don't function so well.

Other experts blame the trans fats produced by partial hydrogenation of industrial oils for processed foods. Trans fats have been shown to interfere with the synthesis of essentials fats in foetuses and infants. Minerals such as zinc and the B vitamins are needed to metabolise essential fats, so deficiencies in these may be playing an important part too.

There is also evidence that deficiencies in DHA/EPA at times when the brain is developing rapidly - in the womb, in the first 5 years of life and at puberty - can affect its architecture permanently. Animal studies have shown that those deprived of omega-3 fatty acids over two generations have offspring who cannot release dopamine and serotonin so effectively.

"The extension of all this is that if children are left with low dopamine as a result of early deficits in their own or their mother's diets, they cannot experience reward in the same way and they cannot learn from reward and punishment. If their serotonin levels are low, they cannot inhibit their impulses or regulate their emotional responses," Hibbeln points out.
You can read the scientific paper about this here. I strongly encourage you to read either the entire article in the Guardian, or the paper.

Sobering, isn't it? My wife has noticed that kids today are dramatically less capable of self-control than when we were young. We've assumed that it was the daycare generation. But perhaps what we are seeing is the dramatic transformation of our diet from the early 1960s when my wife and I were growing up, and the 1980s and 1990s. Do you know that Coca-Cola used to use cane sugar, but they switched to corn syrup some years ago? I believe that the only way to get cane sugar Coca-Cola now is to buy the Kosher for Passover Coca-Cola. (Why corn syrup isn't kosher is explained here.)

I've seen the claim made that corn syrup places a part in increasing myopia--although at least one of the places that I've seen making this claim is selling omega-3 supplements. However, scientific journals have published papers that would indicate some connections between infant diet and visual development that fit into the omega-3 hypothesis.

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