Omega-3, junk food and the link between violence and what we eat

[Guest guest]

Omega-3, junk food and the link between violence and what we eat

 

Research with British and US offenders suggests nutritional

deficiencies may play a key role in aggressive behaviour

 

Felicity Lawrence

Tuesday October 17, 2006

The Guardian

http://lifeandhealth.guardian.co.uk/health/story/0,,1924356,00.html

 

That Dwight Demar is able to sit in front of us, sober, calm, and

employed, is " a miracle " , he declares in the cadences of a prayer-

meeting sinner. He has been rocking his 6ft 2in bulk to and fro

while delivering a confessional account of his past into the middle

distance.

 

He wants us to know what has saved him after 20 years on the

streets: " My dome is working. They gave me some kind of pill and I

changed. Me, myself and I, I changed. "

 

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.

 

Deficiency

 

For the clinician in charge of the US study, Joseph Hibbeln, the

results of his trial are not a miracle, but simply what you might

predict if you understand the biochemistry of the brain and the

biophysics of the brain cell membrane. 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.

 

In Demar's case the aggression has blighted many lives. He has

attacked his wife. " Once she put my TV out the door, I snapped off

and smacked her. " His last spell in prison was for a particularly

violent assault. " I tried to kill a person. Then I knew something

need be done because I was half a hundred and I was either going to

kill somebody or get killed. "

 

Demar's brain has blanked out much of that last attack. He can

remember that a man propositioned him for sex, but the details of

his own response are hazy.

 

When he came out of jail after that, he bought a can of beer and

seemed headed for more of the same until a case worker who had seen

adverts for Hibbeln's trial persuaded him to take part.

 

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.

 

Threat to society

 

Hibbeln is a psychiatrist and physician, but as an employee of the

US government at the NIH he wears the uniform of a commander, with

his decorations for service pinned to his chest. As we queued to get

past the post-9/11 security checks at the NIH federal base, he

explained something of his view of the new threat to society.

 

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 has been a backlash recently against the hype surrounding

omega-3 in the UK from scientists arguing that the evidence remains

sketchy. Part of the backlash stems from the eagerness of some

supplement companies to suggest that fish oils work might wonders

even on children who have no behavioural problems.

 

Alan Johnson, the education secretary, appeared to be jumping on the

bandwagon recently when he floated the idea of giving fish oils to

all school children. The idea was quickly knocked down when the food

standards agency published a review of the evidence on the effect of

nutrition on learning among schoolchildren and concluded there was

not enough to conclude much, partly because very few scientific

trials have been done.

 

Professor John Stein, of the department of physiology at Oxford

University, where much of the UK research on omega-3 fatty acid

deficiencies has been based, agrees: " There is only slender evidence

that children with no particular problem would benefit from fish

oil. And I would always say [for the general population] it's better

to get omega-3 fatty acids by eating fish, which carries all the

vitamins and minerals needed to metabolise them. "

 

However, he believes that the evidence from the UK prison study and

from Hibbeln's research in the US on the link between nutritional

deficiency and crime is " strong " , although the mechanisms involved

are still not fully understood.

 

Hibbeln, Stein and others have been investigating what the

mechanisms of a causal relationship between diet and aggression

might be. This is where the biochemistry and biophysics comes in.

 

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.

 

Mental health

 

Here too you have one possible factor in cycles of deprivation

(again, no one is suggesting diet is the only factor) and why

criminal behaviour is apparently higher among lower socio-economic

groups where nutrition is likely to be poorer.

 

These effects of the industrialisation of the diet on the brain were

also predicted in the 1970s by a leading fats expert in the UK,

Professor Michael Crawford, now at London's Metropolitan University.

He established that DHA was structural to the brain and foresaw that

deficiencies would lead to a surge in mental health and behavioural

problems - a prediction borne out by the UK's mental health figures.

 

It was two decades later before the first study of the effect of

diet on behaviour took place in a UK prison. Bernard Gesch, now a

senior researcher at Stein's Oxford laboratory, first became

involved with nutrition and its relationship to crime as a director

of the charity Natural Justice in northwest England. He was

supervising persistent offenders in the community and was struck by

their diets. He later set out to test the idea that poor diet might

cause antisocial behaviour and crime in the maximum security

Aylesbury prison.

 

His study, a placebo-controlled double blind randomised trial, took

231 volunteer prisoners and assigned half to a regime of

multivitamin, mineral and essential fatty acid supplements and half

to placebos. The supplement aimed to bring the prisoners' intakes of

nutrients up to the level recommended by government. It was not

specifically a fatty acid trial, and Gesch points out that nutrition

is not pharmacology but involves complex interactions of many

nutrients.

 

Prison trial

 

Aylesbury was at the time a prison for young male offenders, aged 17

to 21, convicted of the most serious crimes. Trevor Hussey was then

deputy governor and remembers it being a tough environment. " It was

a turbulent young population. They had problems with their anger.

They were all crammed into a small place and even though it was well

run you got a higher than normal number of assaults on staff and

other prisoners. "

 

Although the governor was keen on looking at the relationship

between diet and crime, Hussey remembers being sceptical himself at

the beginning of the study. The catering manager was good, and even

though prisoners on the whole preferred white bread, meat and

confectionery to their fruit and veg, the staff tried to encourage

prisoners to eat healthily, so he didn't expect to see much of a

result.

 

But quite quickly staff noticed a significant drop in the number of

reported incidents of bad behaviour. " We'd just introduced a policy

of 'earned privileges' so we thought it must be that rather than a

few vitamins, but we used to joke 'maybe it's Bernard's pills'. "

 

But when the trial finished it became clear that the drop in

incidents of bad behaviour applied only to those on the supplements

and not to those on the placebo.

 

The results, published in 2002, showed that those receiving the

extra nutrients committed 37% fewer serious offences involving

violence, and 26% fewer offences overall. Those on the placebos

showed no change in their behaviour. Once the trial had finished the

number of offences went up by the same amount. The office the

researchers had used to administer nutrients was restored to a

restraint room after they had left.

 

" The supplements improved the functioning of those prisoners. It was

clearly something significant that can't be explained away. I was

disappointed the results were not latched on to. We put a lot of

effort into improving prisoners' chances of not coming back in, and

you measure success in small doses. "

 

Gesch believes we should be rethinking the whole notion of

culpability. The overall rate of violent crime in the UK has risen

since the 1950s, with huge rises since the 1970s. " Such large

changes are hard to explain in terms of genetics or simply changes

of reporting or recording crime. One plausible candidate to explain

some of the rapid rise in crime could be changes in the brain's

environment. What would the future have held for those 231 young men

if they had grown up with better nourishment? " Gesch says.

 

He said he was currently unable to comment on any plans for future

research in prisons, but studies with young offenders in the

community are being planned.

 

For Hibbeln, the changes in our diet in the past century are " a very

large uncontrolled experiment that may have contributed to the

societal burden of aggression, depression and cardiovascular death " .

To ask whether we have enough evidence to change diets is to put the

question the wrong way round. Whoever said it was safe to change

them so radically in the first place?

 

Young offender's diet

 

One young offender had been sentenced by the British courts on 13

occasions for stealing trucks in the early hours of the morning.

 

Bernard Gesch recorded the boy's daily diet as follows:

 

Breakfast: nothing (asleep)

 

Mid morning: nothing (asleep)

 

Lunchtime: 4 or 5 cups of coffee with milk and 2½ heaped teaspoons

of sugar

 

Mid afternoon: 3 or 4 cups of coffee with milk and 2½ heaped sugars

 

Tea: chips, egg, ketchup, 2 slices of white bread, 5 cups of tea or

coffee with milk and sugar

 

Evening: 5 cups of tea or coffee with milk and sugar, 20 cigarettes,

£2 worth of sweets, cakes and if money available 3 or 4 pints of

beer.