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Nutrition and LD Charlie MacDowall EPSE 526 July 2008. Overview. Vitamins and minerals Food additives Sugar Water Breakfast studies Fatty acids BC Ministry of Education. Nutrition and LD. Carbohydrates, proteins, fats, vitamins and minerals are the main elements of a healthy diet
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Overview • Vitamins and minerals • Food additives • Sugar • Water • Breakfast studies • Fatty acids • BC Ministry of Education
Nutrition and LD • Carbohydrates, proteins, fats, vitamins and minerals are the main elements of a healthy diet • Deficiencies and over intake may lead to health problems • Some of these may have an effect on behaviour and cognitive ability • Learning difficulties may be associated with poor diet
Vitamins and minerals • Studies by Schoenthaler (2000) with school children and incarcerated juveniles in America, and Gesch (2002) with young, adult prisoners in Britain, demonstrate that vitamins have an effect on behaviour and that imbalances can be corrected with well-balanced diet or vitamin supplementation • Similar study by Benton (1998) noted an increase in cognitive ability of children measured by IQ • Iron deficiency leads to shortened attention span, difficulty concentrating, irritability and fatigue and poor performance on vocabulary and reading tests (Parker 1989)
Food additives • Artificial colours, sweeteners and preservatives • Have been associated with poor behaviour and hyperactivity • However, studies based on the removal of food additives are inconclusive • Recommendation is to remove/reduce food additives for overall health
Sugar • Refined sugar has adverse effects on the body • Short-term effects, short burst of energy, longer period of fatigue • No scientific evidence shows that sugar added to the behavioural problems of hyperactive children • Studies that looked at sugar and cognition did not find a correlation
Water • Evidence of dehydration on the body includes headaches and fatigue • Dehydration can impair concentration and mental performance • Water improves physical and mental performance, helps with health problems such as urinary infections and bed-wetting, protects the body against chronic disease, good for oral hygiene and healthy skin • Important to maintain hydration throughout the school day
Breakfast Studies • Skipping breakfast is very prevalent (10-30% in US and Europe). • Children who report eating breakfast consistently tend to have better nutritional profiles, were less likely to be overweight. • Breakfast consumption may be related to memory, test grades, and school attendance. • Some support for beneficial effects on memory including recall, episodic memory, STM and LTM • Effects of breakfast on other cognitive variables such as attention, problem-solving, reading and listening are less supported • Rampersaud et al., (2005)
Breakfast Studies • Kleinman et al. study: to determine whether nutrient intake and academic and psychosocial functioning improved after the start of a universal-free school breakfast program • Nutritional information from inner city students was gathered before and after USBP (6 months) • At risk= <50% RDA for energy intake and 2+ micronutrients <50% RDA • Prior to USBP, 33% of children in study were at-risk (also had poorer attendance, punctuality, grades, more behaviour problems) • Students who decreased nutritional risk showed significantly greater attendance and school breakfast participation, decreases in hunger, improvements in grades in math and behaviour.
Fatty Acids • role in brain structure and function • Omega-3 and omega-6 FA’s essential for normal brain development and function • EFA’s cannot be synthesized by the body and need to come from dietary sources • HUFA needed by the brain can usually be synthesized from omega-3 and omega-6 FA’s • HUFA that are particularly important in the brain: • Omega-6: AA, DGLA Omega-3: EPA, DHA • If these are not in diet, must be made through desaturation and elongation of simpler FA’s
Fatty acids and dyslexia, dyspraxia and ADHD • Increasing evidence that functional deficiencies and imbalances in these FA’s in ADHD, dyslexia, and dyspraxia (also studies on ASD) • Suggestion that these individuals may differ in their ability to convert EFA to HUFA • Other potential suggestions of FA deficiency: • Overactivity of PLA2 enzyme which removes HUFA from membranes • Other enzymes important in FA recycling and transport • Physical signs of FA deficiency: • Dry hair, dandruff, weak and fraying nails, very rough, dry skin, excessive thirst, frequent urination • These signs have been shown to correlate with blood biochemical measures of HUFA deficiency
Evidence of FA deficiency in dyslexia: • Stordy study (1995): visual function • Dark adaptation shown to be impaired in 10 young adults with dyslexia when compared to control group. With supplementation of omega-3 FA’s EPA and DHA for 1 mo., 5 dyslexic patients showed improvement • Richardson et al. (2004): investigation of reading difficulties • RCT study, 102 children ages 8-12, given placebo or FA treatment • Standardized tests of single word reading and rating scales used • Significant improvements in active treatment group over placebo in reading age
Evidence of FA deficiency in dyslexia cont. • Studies of blood biochemical testing indicating FA deficiencies, increased levels of PLA2 enzyme (removes HUFA from membranes -Baker (1985) and MacDonell et al. (2000) • Clinical signs • large samples of adults with and without dyslexia (Taylor et al., 2000) • Children with more clinical signs had more severe difficulties in reading, spelling and WM (Richardson et al., 2000) • Double-blind trials with supplemenation – showed significant improvements in reading, especially for those with FA deficiency signs at baseline (Richardson et al., 2000)
Evidence of FA deficiency in dyspraxia: • Stordy study: • Group of 15 children with dyspraxia, movement skills (manual dexterity, ball skills, static and dynamic balance) improved after 4 mo. Of supplementation of a mixture of high-DHA fish oil, evening primrose oil, and thyme oil (DHA, EPA, AA and DGLA) • ADHD symptoms were also reduced
Evidence of FA deficiency in ADHD • Males more vulnerable to EFA deficiency-may relate to sex ratio in ADHD • Intolerance of many ADHD children to certain foods such as salicylates (block the formation of prostaglandins from HUFA) • Less likely to have been breastfed (contains preformed HUFA, AA and DHA, that formula does not) • More likely to suffer from allergies (assoc.’d with EFA deficiency) • Clinical signs • Reduced levels of HUFA (AA, EPA, DHA) in blood, but not precursors • Adequate dietary intake of precursors suggests the problem may be the conversion of EFA to HUFA
Further research • Further research using RCT’s are needed • Long-terms benefits need to be looked at • Optimal compositions and dosages need to be explored • Reliable ways to identify who would benefit from these treatments
BC Ministry of Education • Recognizes: • Healthy children are better able to learn • Schools can directly influence a child’s health • Policies and practices that help promote health • ActNowBC’s Daily Physical Activity Log • Revision of guidelines to sale of food and beverages within schools • Healthy Living for Families Booklet
Questions • What are the implications of this for teachers? • How can teachers help?
Main Message • Nutrition must be considered to be a factor in a student’s learning • Good overall nutrition is beneficial for all students • FA deficiencies should be considered for students with LD
Key References • BC Healthy Schools Website • www.bced.gov.bc.ca/healthwelcome.htm • Healthy Schools Publications for Families • www.bced.gov.bc.ca/health/tools.htm • Research • Dani, J., Burrill, C, & Demming-Adams, B. (2005). The remarkable role of nutrition in learning and behaviour. Nutrition and Food Science, 35:4, 258-263 • Richardson, A.J. (2004). Clinical Trials of Fatty Acid Treatment in ADHD, dyslexia, dyspraxia, and the autistic spectrum. Prostaglandins, Leukotrienes, and Essential Fatty Acids. 70:4, 383-390