Docosahexaenoic acid (DHA)

Attention deficit disorders–drugs or nutrition?
Matsudaira T.
Nutr Health. 2007;19(1-2):57-60.

 3-9% of schoolchildren in the U.K. suffer Attention Deficit and Hyperactivity Disorder (ADHD). Since the 1950s stimulants have been used. particularly methylphenidate and dextroamphetamine, with some 75% response rate. The first non-stimulant medication–atmoxetine hydrochloride, has also been used. However, side effects have included: growth retardation; appetite loss: headache: stomachache: heart problem: insomnia: seizure; change of character: addiction or even suicidal thoughts. Alternative treatments have been used including omega-3s, yet the way they benefit in ADHD is uncertain. They may be important in remodelling dendrites and synapses, and/or sustaining: blood brain barrier, neuronal membrane. neurotransmitter channel, receptors and ion channel. Stevens in 2003 found long-chain polyunsaturated fatty acids (LCPUFAs) effective for oppositional defiant disorder, whereas Eicosapentaenoic acid (EPA) specifically was helpful with disruptive behaviour. Docosahexaenoic acid (DHA) is important during gestation and early infancy, particularly for neurodevelopment. The Durham Trial by Richardson published in 2005, tested omega-3s with omega-6s on schoolchildren with developmental coordination disorder (many of them had ADHD symptoms), improving scores in co-ordination and short term memory. PMID: 18309764

  Resting state electroencephalographic correlates with red cell long-chain fatty acids, memory performance and age in adolescent boys with attention deficit hyperactivity disorder.
Sumich A, Matsudaira T, Gow RV, Ibrahimovic A, Ghebremeskel K, Crawford M, Taylor E.
Neuropharmacology. 2009 Dec;57(7-8):708-14

 Abnormal fatty acid status has been implicated in the aetiology of attention deficit hyperactivity disorder (ADHD). Delayed maturation in ADHD may result in raised frontal low frequency (theta) electroencephalographic activity (EEG) and a reduction in posterior high frequency (beta, alpha) activity. The current study used sequential linear regression to investigate the association between age, resting-state EEG and levels of long-chain polyunsaturated omega-3 and omega-6 fatty acids in red blood cells in 46 adolescent boys with ADHD symptoms. Docosahexaenoic acid (DHA) levels were positively associated with fast frequency activity: alpha during eyes-open and beta during eyes-closed conditions. Frontal theta activity during both eyes-open and eyes-closed conditions was inversely associated with age and positively associated with eicosapentaenoic acid (EPA) levels. Alpha activity correlated positively with performance on fluency for categories (semantic memory). Theta activity correlated inversely with performance on delayed (25 min) verbal memory (recall + recognition/2). No associations were observed between long-chain omega-6 and EEG measures. Results support differential associations for DHA and EPA with fast and slow EEG activity respectively. Results support EEG activity as an objective biomarker of neural function associated with long-chain omega-3 fatty acids in ADHD. PMID: 19627997

  Neurophysiologic and neurobehavioral evidence of beneficial effects of prenatal omega-3 fatty acid intake on memory function at school age.
Boucher O, Burden MJ, Muckle G, Saint-Amour D, Ayotte P, Dewailly E, Nelson CA, Jacobson SW, Jacobson JL.
Am J Clin Nutr. 2011 May;93(5):1025-37

 The beneficial effects of prenatal and early postnatal intakes of omega-3 (n-3) polyunsaturated fatty acids (PUFAs) on cognitive development during infancy are well recognized. However, few studies have examined the extent to which these benefits continue to be evident in childhood. The aim of this study was to examine the relation of n-3 PUFAs and seafood-contaminant intake with memory function in school-age children from a fish-eating community. In a prospective, longitudinal study in Arctic Quebec, we assessed Inuit children (n = 154; mean age: 11.3 y) by using a continuous visual recognition task to measure 2 event-related potential components related to recognition memory processing: the FN400 and the late positive component (LPC). Children were also examined by using 2 well-established neurobehavioral assessments of memory: the Digit span forward from Wechsler Intelligence Scales for Children, 4th edition, and the California Verbal Learning Test-Children’s Version. Repeated-measures analyses of variance revealed that children with higher cord plasma concentrations of docosahexaenoic acid (DHA), which is an important n-3 PUFA, had a shorter FN400 latency and a larger LPC amplitude; and higher plasma DHA concentrations at the time of testing were associated with increased FN400 amplitude. Cord DHA-related effects were observed regardless of seafood-contaminant amounts. Multiple regression analyses also showed positive associations between cord DHA concentrations and performance on neurobehavioral assessments of memory. To our knowledge, this study provides the first neurophysiologic and neurobehavioral evidence of long-term beneficial effects of n-3 PUFA intake in utero on memory function in school-age children. PMID: 21389181