Why it's time we faced fats
New research establishes a link between nutrition and the management of many behaviour and learning disorders. Felicity Lawrence investigates
It takes about four months to get an appointment at the dyslexia clinic at Oxford University's department of physiology. Joshua's turn has finally come - he is eight-years-old, clever, well-behaved and doing well, but an energetic special needs teacher at his primary school has picked up that, in some areas, he is underperforming for his ability and suspects he may have dyslexia. In a tiny room, barely more than a cupboard, Sue Fowler - who has a doctorate in visual physiology - is using simple equipment to check his vision. The clinic is free, funding is short, and it's all a bit make-do. She positions the prongs of a long, fork-like stick on Joshua's face so that he has to look down the stick's length at a small box with a black dot on it. As she pushes the box up the stick towards his face, he has to tell her when the one dot becomes two. It does so almost immediately.
Joshua has already passed his NHS eye test but one vital point was missed by the optician - "It often is these days..." sighs Sue. "He's got a problem with convergence. His eyes are working separately and seeing double, which means that when he tries to read, the letters are blurred and jumping around."
She gives him a pair of blue glasses from Taiwan worth 50p that make things better immediately. "Blue quietens down the magnocellular pathway in the brain," she says.
The magnocellular pathway is the one by which the brain perceives motion or where things are, as opposed to the parvocellular pathway that sees fine detail and colour, or what things are. We still know little about how the two pathways interact or about how colour works, and the treatment in Joshua's case is as simple as the neuroscience behind it is complicated. This is the cutting edge of brain research.
The Oxford scientists estimate that about two thirds of the children they see have difficulty with controlling eye movements and with visual attention, which arises from problems with the magnocellular pathway of the brain. About a third benefit from another low-tech intervention - supplements of fish oils, high in the Omega-3 series of essential fatty acids vital to the brain's structure and to the functioning of the magnocellular pathway but deficient in most modern diets.
The lab buildings here in Oxford are where John Stein, professor of physiology and brother of chef Rick, has gathered a team of researchers whose studies into the brain are beginning to challenge the very notion of free will.
In a series of trials, they have found that dyslexia, dyspraxia, attention deficit and hyperactivity disorder (ADHD) can all be dramatically improved by simple nutritional supplements. Their work exploring the biological basis of personality and behaviour suggests we may need to rewrite the books on crime and punishment. Revealing as it does that mood, behaviour and achievement are affected by whether the brain has enough of the right kind of nutrients to function properly, it throws into doubt how far anyone, from the disruptive child to the convicted criminal, can actually control their behaviour.
The department's latest work was published earlier this week by Stein's colleague Alexandra Richardson. She studied more than 100 children of normal ability in mainstream schools in County Durham, who were underachieving and suspected of being dyspraxic - that is of having problems with coordination or motor skills. In some cases, the children were also disruptive.
Once they had been assessed, they were divided into two groups for a randomised double-blind, placebo-controlled trial. Half of them were given fish oils high in Omega-3 essential fats for three months. The other half were given placebos. Some 40% of the children given supplements made dramatic improvements in reading and spelling, averaging progress of more than nine months in just three months. The control group made just the normal progress of three months.
Although none had been diagnosed as suffering from ADHD, a third were found to have sufficient problems to put them in this category. But when given fish oils, half of them made so much progress they no longer counted as having attention disorders - a change on a par with improvements made when children are prescribed stimulant drugs such as Ritalin.
The raw data disguises the excitement and relief experienced by many of the parents whose children were being treated. After three months, the control group switched from placebos to active supplements, and showed similar leaps in progress.
The physiological mechanisms by which deficiencies of essential fats in the diet might affect the working of the brain are becoming clearer. Apart from water, the brain is largely made up of essential fats. The Omega-3 essential fatty acid DHA is concentrated in the synaptic junctions and signalling system of the brain and retina, for example. Another Omega-3 fatty acid, EPA, is also vital for cell signalling.
These essential fatty acids are so called because they cannot be synthesised in the body, but have to be eaten in the diet. Fish is the best source. Nuts, seeds and leafy vegetables also provide them. Modern industrial processing strips many of the vital Omega-3 fatty acids from our food because they are unstable and liable to go off. Hydrogenating fats also wipes out Omega-3s.
In the past, the ratio between Omega-3s and Omega-6s in the diet would have been in balance, now we consume between 10 and 20 times as much Omega-6 as Omega-3 fat.
As these changes in our diet have taken place, a range of disorders have become alarmingly common: current evidence suggests that up to 20% of the population may be affected by dyslexia, dyspraxia, ADHD or autistic spectrum disorders. These conditions are in fact, as Richardson points out, little more than descriptive labels for a range of traits and features that overlap with more severe disorders such as full autism, schizophrenia and manic depression. Other studies into these three conditions show that taking essential fatty acids supplements is an effective treatment for them, too.
But our approach to many of these disorders is still hung up on pharmacological or psychological treatments. "Food affects behaviour, but at the moment, nutrition is neglected or ignored, even in children whose needs are obviously not being met in the education system. But if you paid attention to diet, you could really make a difference," Richardson says.
The implications of a study conducted by another researcher in Stein's department are even more startling. In another randomised, double-blind, placebo-controlled trial, Bernard Gesch gave a course of supplements containing essential fatty acids and key vitamins and minerals to prisoners in one of Britain's maximum security prisons. The inmates were responsible for some of the highest levels of prison violence in the UK. The number of serious offences, including violence, by the prisoners, fell by nearly 40% in those taking the supplements but not at all in those not taking them. To Gesch, the case is just "bleeding obvious". "The brain is a metabolic powerhouse, which despite being only 2% of our body mass, consumes around 20% of available energy. To metabolise this energy requires a range of nutrients, vitamins, minerals and essential fatty acids. These are essential for the normal functioning of the brain, which means there are likely to be consequences if we don't get enough of them from our diet."
The Dutch government has been so impressed by the results of the prison study that it is starting its own programme. The American and French prison services have expressed interest too, but so far the British Home Office is not convinced. It says it wants to see the study replicated on a larger scale but there is no funding to do the work.
Stein finds it very frustrating. "Our mindset is so sociological, we don't look for the physiological explanations. An awful lot of money goes into cognitive approaches to criminology, though they've never been shown to work." He speculates that it's no coincidence that most crime and antisocial behaviour is committed by young pubescent males when their rapidly growing bodies have to compete with their brains for nutrients inadequately provided by junk food diets.
"Around puberty is a really crucial time - it's the second big burst of brain development [after foetal development]."
But the ideas are being taken up with enthusiasm elsewhere. Jamie Oliver visited Stein while preparing his series on school dinners. It was the hard-slog science of the physiology department that gave credibility to the link between children's diet and their behaviour that Oliver made so powerfully in his TV programmes.
Ordinary people are desperate to know more about the way our food affects our mental state. But unless new money is found soon, the Oxford department's researchers will be unable to continue.
Meanwhile, Stein's best advice to the rest of us might be to cut out the junk food and try his brother's fish recipes at least twice, ideally three times, a week instead.
http://www.fabresearch.org/ Details of Dr Richardson's and others' research on food and behaviour
http://www.dyslexic.org.uk/ Dyslexia Research Trust charitable website
Chemicals that keep the brain sharpThe brain, the nervous and vascular systems, and to a lesser extent, all cells in the body use a special kind of fat in their construction, known as essential fat. The brain alone is comprised of three quarters of this fat, which has a different chemical composition to the visible fat the body uses as a way of storing energy. At a molecular level, fat is comprised of a string of carbons, saturated with hydrogen and with an acid group at one end. The carbon atoms are normally joined by single bonds. With some fats, some of the hydrogens can be moved to form double bonds between adjacent carbons. Essential fatty acids have more than one double bond and are called polyunsaturated.
There are two different types of essential fatty acids:
- Linoleic acid and its derivatives, including arachidonic acid (AA), are known as the Omega-6 series of fatty acids;
- Alpha-linolenic acid and its derivatives are the Omega-3 series of essential fatty acids, which include EPA and DHA.
These essential fatty acids cannot be made in the body and must be eaten in the diet. Animals and fish eat the plants containing the shorter chain fatty acids, and their digestive systems change the fat, extending the length of the carbon chain. When people eat meat or fish they build on these building blocks again. It is the long chain fatty acid derivatives that are used in human brain construction, in particular in the construction of cell membranes. These different chemical structures give the fats different properties: saturated fats are hard and inflexible, while polyunsaturated fats are liquid. Essential fats are unstable, so they are stripped from foods by industrial processing where shelf life and stability are considered more important.
In 1972 Michael Crawford showed that both AA and DHA were used in forming the structure of the brain. DHA is concentrated in the synaptic junctions and signalling systems of the brain and retina. EPA and its derivatives are vital for cell signalling.
All chemical and electrical signals have to pass through the outside walls or membranes of the brain cells that are made mostly of fats. When the cells react to a stimulus, little holes in the membrane open and close to produce electric impulses. With the right kind of fat, that is a lot of DHA, they are more elastic and signals can be passed rapidly and efficiently. The cells also release signalling molecules derived from EPA, so for the brain to work well, you need to have more EPA to replace them.
John Stein's theory is that a whole range of neurophysiological conditions and disorders from dyslexia and dyspraxia to depression and schizophrenia relate to problems with the magnocellular part of the brain's visual system and how signals are passed within it.
People no longer consume enough essential fatty acids for the brain to function properly, and some people inherit a vulnerability to Omega-3 deficiency.
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