During the last century there was a push for people to eat more protein, the emphasis being on building a healthy body. However as early as 1970, Professor Michael Crawford, Director of IBCHN at the London Metropolitan University and Professor Andrew Sinclair of Deakin Univeristy, Australia (pioneers of research into the effects of omega fatty acids on the brain) predicted that, whatever about protein, unless there was a significant increase in fatty acids in our diets, then brain disease would become as common as heart disease… and indeed brain disorders have now over taken all others as the main burden of ill health, costing £77 billion in 2007 in the UK alone. Many independent neuroscientists and nutritionists are now warning of a potential mental health epidemic.
So what are essential fatty acids, and why are they so important? Numerous research papers have shown that people with bipolar and schizophrenic disorders, and depression, have lower levels of DHA (docosahexaenoic acid). Additionally, supplementation with DHA reduces risk of transitioning to psychosis in high-risk young adults while treatment with DHA and EPA (eicosapentaenoic acid) reduces depression in children.
Humans can be called the animal of the runaway brain – compared to many other mammals our brains are vast and consist mostly of essential fatty acids, meaning that our need for DHA is great, particularly when we are in the womb when our brains are being built.
However, the scientists have signally failed to get this need for DHA and EPA across to the government or the public. The US and UK’s Governments have advised that pregnant women eat no more than 12 ounces of fish per week even though studies on fish-eating nations has shown there is no evidence that methyl-mercury in our polluted seas has an adverse effect.
Plants also contain essential fatty acids, but the human body’s ability to convert these into brain-supporting DHAs is minimal. Scientists and nutritionists are therefore encouraging the Government to raise the level of fish consumption it recommends for pregnant women, and to instigate DHA supplementation for individuals with brain disorders.
At a two-day conference held at the end of May 2010 to celebrate the discoveries and achievements in the field of DHA over the last 40 years, many of the world’s top scientists presented study after study supporting the need for Governments to take the initiative.
The first afternoon concentrated on the evolution of the brain, covering the geophysical evidence and looking at our aquatic origins with a launch of Stephen Cunnane and Kathlyn Stewart’s book ‘Human Brain Evolution: the influence of freshwater and marine food resources’ (published by John Wiley and Sons). See here for more information on these sessions.
On day two, as the scientists gave their papers, each paid tribute to Professor Michael Crawford, for his over 50 year’s of seminal work on the brain. Here are some of the highlights from their presentations:
Discovery: The Essential Fatty Acids
Andrew Sinclair, Professor of Nutrition Science, Deakin University, Australia: Crawford-omics: a platform for the future
In the early days, after the discovery of EPA in the 1930s, nutritionists were unsure whether omega 3 poly-unsaturated fatty acids (PUFAs) had a role to play in warm-blooded species. But Michael Crawford began to observe the human brain’s dependency on omega 3s. His studies from the 1960s onwards underpinned subsequent research into the role of DHA in the food supply of infants, children and the elderly.
Claudio Galli, Professor of Pharmacology, University of Milan:
Essential fatty acid deficiency
The inefficient conversion of plant-based fatty acids to DHA was not recognised for a long time, so the importance of DHA in the diet has been underestimated. It is relatively easy to measure DHA deficiency, so most studies are devoted to conditions caused by a lack of essential fatty acids. As a result, optimum or recommended intakes are still undefined. A method of systematic assessment of fatty acid status in humans must be developed to determine correlations between levels of DHA in the blood and physiological conditions. This will then allow for correct supplementation recommendations for different individuals.
Laurence Harbige, Reader in the School of Science, Universities at Medway Campus, Kent: AA and CNS Autoimmune Disease
Saturated fats are positively associated with Multiple Sclerosis whereas omega 3 and 6 fatty acids are negatively associated. The relapse rate for MS was reduced by treatment with fatty acids. Studies have shown that MS patients lose fatty acids rapidly.
Rodolfo Brenner, Emeritus Professor, University of La Plata, Argentina:
The desaturase system
This complicated presentation relayed the mechanism of biosynthesis of unsaturated fatty acids, its regulation and effects. Generally the human diet is rich in linoleic acid and poor in linolenic and arachidonic acids (AA), and DHA. Linoleic acid is accumulated in adipose tissue (fat), whereas linolenic acid is quickly oxidised and converted into polyunsaturated fatty acids (the kind our brains need to maintain health)
Illnesses like diabetes depress EPA and AA deposits in body, but not in the brain. Therefore there is a need to increase the proportion of DHA in the diets of those with this type of illness. And the main way to provide DHA to body is with food, including some species of fish.
Discovery: DHA, the brain and the eye
Tom Brenna, Professor of Human Nutrition, Cornell University, USA: DHA and brain development: primate models
Omega 3 deficiencies can be reversed. In studies on newborn monkeys, those supplemented with DHA had an earlier maturation of brain/eye development than those that were given no supplementation. DHA is everywhere in the brain, especially in regions of grey matter.
Susan Carlson, AJ Rice Professor of Nutrition, University of Kansas Medical Centre, USA: DHA in infant formulas
In a 1978 study, breast fed babies were found to have more long chain PUFAs in their cell membranes than formula fed babies. A 1979 study showed that breast fed babies had twice as much DHA than either of the two formula fed groups. Less DHA in the brain meant lower visual acuity (Connor, Neuringer 1982). DHA accumulates in the brain beginning at 20 weeks gestation. The effects of lower brain DHA suggest potential for lower cognitive function including problem solving, attention = look duration, sustained attention, distractibility; cognitive development and IQ. There is strong evidence for benefit of DHA supplement of children in first year of life. If a baby consumes DHA it will have more DHA in brain. There is new evidence that DHA may enhance development of the immune system. DHA composition in mother’s and breast milk is very variable around the world.
Nicolas Bazan, IBCHN, London Metropolitan University, UK:
DHA and neuroprotectins
DHA/Neuroprotectin D1 are sentinels for the preservation of vision, brain function, counteracting neuroinflammation and inducing reduction in Alzheimer’s. DHA levels increase after injury. DHA helps stroke patients recover.
Achievements: DHA in clinical medicine Hee-Yong Kim, Chief, Laboratory of Molecular Signalling, National Institutes of Health, USA: DHA and signalling mechanisms
DHA is known to be critical for optimal brain development and function. Mechanisms for DHA’s beneficial effect are not clearly understood at present. This research has shown that DHA supplementation inhibits neuronal cell death (and neuronal cells are almost impossible to revive, so prevention is important), supporting a notion that DHA is an important neuro-protective agent. DHA promotes key signalling mechanisms in the brain, and contributes to learning and memory.
Michael Lagarde, Professor of Biochemistry & Molecular Biology, Lyon National Institute of Applied Science, France:
DHA and redox potential
Fatty acids of the omega 3 family, especially long chain from marine origin are assumed to prevent cardiovascular disease. But EPA and DHA are susceptible to oxidative stress, symptoms of which have been reported after intake of large amounts.
By contrast, in low concentrations they may exert an antioxidant effect in blood platelets by mechanisms yet to be clarified. Results support 500mg EPA/DHA recommendations for daily intake.
Bruce Holub, Dept. of Human Health & Nutritional Sciences, University of Guelph, Canada: EPA, DHA and cardiovascular health
Supplementation with an algal source of DHA increases fatty acid status and alters selected risk factors of heart disease in vegetarian subjects. Omega 3 supplementation had a significant effect on sudden death and coronary death – for more information visit www.Dhaomega3.org
Norman Salem, Emeritus Professor, University of La Plata, Argentina: DHA – a required nutrient in health and cognition
Fish intake correlates with reduced risk of dementia and improved cognitive scores.
Research shows that taking DHA for 6 months made the brain 3 years younger and maintains and improves brain health in older adults. It improves learning and memory recall and decreases heart rate also demonstrating cardiac health benefits.
Joe Hibbeln, Psychiatrist, Acting Chief, Section on Nutritional Neurosciences, NIH: Changes in 20th century fat intake and mental health
Omega 3 deficient diets deplete dopamine in the frontal cortex of our brains, and this is important because we experience our brains predominantly through emotion. If we have no dopamine to release we have no sense of reward from pleasurable experiences, eg eating, seeing family, etc.
Letten F Saugstad, Institute of Neuroscience, University of Oslo, Norway:
The designer of the brain is evolution, but nerve cells themselves are the builders. To secure optimal function we need to provide optimal nutrition, which, currently, we do not!
Supporting the Celebration of DHA, the Royal Society of Medicine is hosting an exhibition until the end of June 2010: Why the brain is under siege in the 21st Century: some insights from nutrition during human evolution.
For help understanding some of the terms used in these presentations, you may find it useful to visit the website of Efamol, a producer of a wide range of EFA products.
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