Iodine is an essential mineral required for thyroid function.  Iodine deficiency is associated with goitre, as well as impaired mental and physical development.

The effects of severe iodine deficiency during critical periods of brain development are well documented.  Iodine deficiency results in a range of conditions collectively termed ‘iodine deficiency disorders’ including neurological cretinism.  During childhood, iodine deficiency can cause delayed bone maturation and reduction in intellectual quotient (IQ).  It can leads to permanent neurological damage if treatment is delayed.

Studies have found that there is a wide spread of iodine deficiency in Australia and New Zealand. To determine whether supplementing mildly iodine-deficient children with iodine improves cognition.  New Zealand researchers conducted a double-blind, placebo-controlled trial in 184 children aged 10–13 y in Dunedin, New Zealand.

Children were randomly assigned to receive a daily tablet containing either 150 mcg of iodine or placebo for 28 wk.  Biochemical, anthropometric, and dietary data were collected from each child at baseline and after 28 wk.  Cognitive performance was assessed through 4 subtests from the Wechsler Intelligence Scale for Children.

After 28 weeks, the study found that iodine supplementation improved iodine status in the supplemented group.  It also significantly improved scores for 2 of the 4 cognitive subtests and matrix reasoning.  The overall cognitive score of the iodine-supplemented group was higher than that of the placebo group.

Based on these findings, the study authors concluded that iodine supplementation improved perceptual reasoning in mildly iodine-deficient children, and raised the concern that mild iodine deficiency could prevent children from attaining their full intellectual potential.

Source:
Rosie C Gordon et al; Clin Nutr 2009; 90:1264–71.

It is estimated that 25% of the world’s population, and approximately 50% of pre-school children worldwide have anaemia.  50% of anaemia cases are due to iron deficiency.  Studies have shown that iron deficiency in infancy is related to poorer cognition in childhood.

Iron is an essential mineral that plays key function in oxygen transport and storage.  Iron deficiency is associated with fatigue, lethargy, impaired cognitive and motor function.  The risk factors of developing iron deficiency anaemia (IDA) include low iron intake, poor absorption of iron, and high iron demand particularly during infancy, growth spurts, adolescence, and pregnancy.  In observational studies anaemia and iron deficiency are associated with cognitive deficits, suggesting that iron supplementation may improve cognitive function.

A recent meta-analysis assessed whether iron supplementation improved cognitive functions including concentration, intelligence, memory, psychomotor skills and scholastic achievement.  Fourteen RCTs on iron supplementation in males and females aged 6 years and older were included in this analysis.

This analysis found that iron supplementation improved attention and concentration irrespective of baseline iron status.  In anaemic women and children, supplementation improved intelligence quotient (IQ) by 2.5 points, but had no effect on non-anaemic participants, or on memory, psychomotor skills or scholastic achievement.

Findings from this analysis provided evidence on the benefits of iron supplementation on cognitive function, however, further studies of at least one year’s duration with varying levels of baseline iron status and using well validated tests of cognition are needed to confirm and extend these results.

Source:
Falkingham et al. Nutrition Journal 2010, 9:4

Korean Ginseng (Panax Ginseng) is an adaptogenic herb that has been used as potent energy tonic for thousands of years in Traditional Chinese Medicine. Modern clinical study has provided scientific evidence on its benefit in enhancing cognitive performance.

Although we do not yet fully understand the mechanism for many of Ginseng’s medicinal benefits, modern science using controlled clinical trials began to unravel scientific evidence on the health benefits of Ginseng supplementation.  Single doses of the traditional herbal treatment Panax ginseng have recently been shown to lower blood glucose levels and elicit cognitive improvements in healthy, overnight-fasted volunteers.

In a double-blind, placebo-controlled clinical trial, 27 healthy young adults completed a 10 minute “cognitive demand” test battery at baseline.  The 10 minute “cognitive demand” battery comprised a Serial Threes subtraction task (2 min); a Serial Sevens subtraction task (2 min); a Rapid Visual Information Processing task (5 min); and a “mental fatigue” visual analogue scale.

These young adults then consumed capsules containing either a Panax ginseng extract or a placebo, and 30 minutes later a drink containing glucose or placebo. A further 30 minutes later (i.e. 60 minutes post-baseline/capsules) they completed the “cognitive demand” battery six times in immediate succession.  The participants were divided into four groups: Placebo (0mg Ginseng/0 mg glucose); Ginseng (200mg Ginseng/0 mg glucose); Glucose (0 mg Ginseng/25 g glucose); or Ginseng/Glucose (200 mg Ginseng/25 g glucose).  Blood glucose levels were measured prior to the day’s treatment, and before and after the post-dose completions of the battery.

The results showed that both Panax ginseng and glucose enhanced performance of a mental arithmetic task, and ameliorated the increase in subjective feelings of mental fatigue experienced by participants during the later stages of the sustained, cognitively demanding task performance.  Accuracy of performing the Rapid Visual Information Processing task (RVIP) was also improved following the glucose load.  Panax ginseng caused a reduction in blood glucose levels 1 hour following consumption when ingested without glucose.

These results confirm that Panax ginseng may possess glucoregulatory properties and can enhance cognitive performance.

Source:
Reay JL etal; Journal of Psychopharmacology 2006; 20(6):771-81

Approximately 310,000 Australians suffer from chronic heart disease and is the second largest disease burden to Australian economy.  The total direct healthcare cost attributed to cardiovascular disease is AUD$5.9 billion each year in Australia.  A latest health economic analysis by Deloitte Access Economics showed that fish oil supplementation is a cost-effective intervention to prevent future cardiovascular mortality and morbidity in Australia.

Fish oil supplements offer a number of advantages through lowering potential risk profiles. The World Health Organization (WHO), American Heart Association, National Health and Medical Research Council (NHMRC), and the National Heart Foundation of Australia recommend fish oil as a complementary treatment in addition to standard treatments following a Myocardial Infarction (MI), commonly known as heart attack. MI typically occurs when the blood supply to parts of the heart is cut off by a blocked artery, causing damage to the heart tissue, and the cells in the affected area to start to die. In the days and weeks following a cardiac incident, this area may grow, eventually leaving a large part of the heart unable to function properly and increasing the risk of further heart problems.

Epidemiological studies have shown that the consumption of fatty fish is associated with lower incidence rates of coronary heart disease (CHD), stroke and MI.  The Complementary Healthcare Council of Australia (CHC) recently commissioned Deloitte Access Economics to undertake cost benefit analysis (CBA) of fish oils and estimate the net benefit of fish oils as adjunctive treatment for prevention of heart disease among those who have experienced MI, versus no fish oils, taking into account the cost per person of the treatment and the DALYs (Disability-Adjusted Life Years) avoided. DALY is a measure of overall disease burden adopted by WHO.

The analysis by Deloitte Access Economics is based on fish oil supplementation with dosage of 510-540mg EPA/day and 345-360mg DHA/day.  The result showed an ICER (incremental cost-effectiveness ratio) of $2,041 per DALY averted, indicating that fish oils are cost effective in the secondary prevention of CHD relative to the WHO benchmark.  The maximum value of the DALY benefits from the fish oil intervention was estimated at up to $3.4 billion.

This latest report offers further evidence that fish oil supplementation not only is effective in the reduction of incidence rates for cardiovascular disease, but also offers a genuine opportunity to reduce disease burden in a cost effective manner.

Source:
CHC Report on Fish oils for the secondary prevention of Coronary Heart Disease, 17 Feb 2012

Fats are a necessary part of dietary energy supply.  However the quality of dietary fats, particularly long-chain Polyunsaturated fatty acids (PUFAs), plays critical roles in physiological functions such as central nervous system (CNS) development and visual function in infants and children.  In addition, the effect of dietary fats on lipids metabolism at an earlier age may be associated with cardiovascular mobidity and mortality in later life.

In recent years, there has been growing researches in the quality of dietary fat intake in early life as a major determinant of growth and development in children as well as long-term health.  The selection of dietary fatty acid sources during the first years of life is now considered to be of critical importance.

Lipids are structural components of all tissues and are indispensable for the assembly of membranes and cell organelles. The brain, retina and other neural tissues are particularly rich in long-chain polyunsaturated fatty acids (PUFAs).  For example, docosahexaenoic acid (DHA), a type of long-chain omega-3 PUFA, is a critical component of cell membranes, especially in the brain and the retina, and plays an important role in brain and visual function, due to its high content in cerebral cortex and retinal phospholipids.  DHA is considered conditionally essential during early development in childhood.

During the first 6 months of life, dietary total fat should contribute 40–60% of total energy to cover the energy needed for growth and the fat required for tissue deposition. From age 6 months to 3 years, fat intake requirements are reduced gradually to approximately 30–35% of energy depending on the physical activity of the child.  Many health organizations recommend that daily DHA intake should be between 0.2-0.5% of total fat intake for infants.  The daily Omega-3 intake for prevention of nutrition-related chronic disease should ideally fall within 1-2% of total energy intake for children over 2-yrs of age.

Vegetarian source of fats has virtually no long-chain PUFA unless algae are included in the diet.  Fish is the major source of the two important PUFAs – DHA and EPA.  Recent scientific evidence have shown that direct supply of DHA and EPA in the diet provides many health benefits including retinal and brain development and function during early childhood, cardiovascular health, inflammatory response, and allergy.  Balanced dietary intake of beneficial fats in childhood can influence risk of Cardio Vascular Diseases (CVD) later in life.

In summary, lifelong intakes of EPA and DHA are associated with reduced risk of cardiovascular disease and metabolic syndrome, as well as optimal mental development, behaviour, and immune response. Since the dietary intakes of EPA and DHA among infants and children in many western and non-western countries are lower than desirable on a unit of body weight basis and as percent of total energy, it is prudent that parents take measures to ensure that their children obtain optimal levels of EPA and DHA through diet and supplementation where required.

Source:
R Uauy and AD. Dangour; Ann Nutr Metab 2009;55:76–96

A study published in the Nutrition Journal compared the macronutrient and micronutrient levels in the foods chosen by women following two different weight reduction programs.

Ninety-six generally healthy overweight or obese women randomly placed into two treatment groups: Traditional Food Group (TFG) or a Meal Replacement Group (MRG). The MRG included the use of 1-2 meal replacement drinks or bars per day. Both groups aimed to restrict energy levels to approximately 1,300 calories per day. After one year, weight loss was not significantly different between the groups, and both groups had macronutrient (Carbohydrate:Protein:Fat) ratios that were within the ranges recommended. Both groups experienced an improved dietary pattern with respect todecreased saturated fat, cholesterol, and sodium, with increased total servings/day of fruits and vegetables. However, the TFG had a significantly lower dietary intake of several vitamins and minerals compared to the MRG and were at greater risk for inadequate intake.

Although both groups successfully lost weight while improving overall dietary adequacy, the group incorporating fortified meal replacements tended to have a more adequate essential nutrient intake compared to the group following a more traditional food group diet. This study supports the need to incorporate fortified foods and/or dietary supplements while following an energy-restricted diet for weight loss.

Source:
Ashley JM et al. Nutr J. 2007 Jun 25; 6:12.

In a large observational study, research scientists monitored 810 children from 5 to 12 years of age seeking medical help for ADHD, whom have been recommended by a physician to take  omega-3 and omega-6 polyunsaturated fatty acids (PUFA) supplementation in combination with zinc and magnesium over a period of at least 3 months. The objective of the study was to evaluate the nutritional effects of the PUFA-zinc-magnesium combination on symptoms of attention deficit, impulsivity, and hyperactivity as well as on emotional problems and sleep related parameters. Assessment was performed by internationally standardized evaluation scales, i.e. SNAP-IV and SDQ.

After 12 weeks of supplementation, most children showed a considerable reduction in symptoms of attention deficit and hyperactivity/impulsivity assessed by SNAP-IV.  Further, the assessment by SDQ revealed fewer emotional problems at the end of the study period compared to baseline and also sleeping disorders. Problems with falling asleep decreased during the 12 week nutritional therapy.

Due to the poor dietary patterns in industrialized western countries, with high amounts of processed food products containing mostly very low levels of long chained omega-3 fatty acids (DHA and EPA), there is a discrepancy between desirable and actual intake of these important essential fatty acids in both adults and children. Results from this study suggest a low risk, favourable beneficial effect of omega-3 and omega-6 fatty acids supplementation combined with magnesium and zinc on attentional, behavioural, and emotional problems of children and adolescents.

Source:
Huss et al. Lipids in Health and Disease 2010, 9:105

In parallel with increasing prevalence of obesity in adolescents, it is expected that long-term morbidity in this population will increase.  A recent Australian research investigated the association between measures of adiposity (body mass index and waist circumference) and risk factors for heart disease, type 2 diabetes, fatty liver disease, and the clustering of risk factors in middle adolescence.

496 year 10 students (mean age – 15.4 years) in the Sydney metropolitan area were included in this study.  Blood samples were collected for biomarker studies including lipids (HDL and LDL cholesterol, triglycerides), insulin and glucose, liver health (ALT and GGT), high-sensitivity CRP (a marker for inflammation and risk predictor for cardiovascular disease), and blood pressure.

The study found that:

• The prevalence of overweight and obesity in adolescent boys was 27.6%, based on BMI (body mass index calculated as weight in kilograms divided by height in meters squared), and 20.0% based on waist circumference cut points. The prevalence of overweight and obesity in adolescent girls was 19.4% based on BMI and 18.0% based on waist circumference.
• Adolescent boys are more likely to have multiple risk factors than adolescent girls, particularly if they are overweight or obese.
• 95% of obese and 80% of overweight adolescent boys had at least 1 risk factor.
• Obese adolescent boys and girls were significantly more likely to have 2 or more risk factors than non-overweight adolescents.
• The cardiovascular risk factors were relatively common, with high blood pressure being the most prevalent risk factor in adolescent boys (22.1%) and girls (10.8%).
• Low HDL cholesterol levels and elevated high sensitivity-CRP levels were also relatively common, with 10.7% of adolescent boys and 3.9% of adolescent girls having low HDL cholesterol levels and 7.5% of adolescent boys and 8.6% of adolescent girls having high hs-CRP levels.
• 4.5% of adolescent boys and 6.3% of adolescent girls have abnormal LDL cholesterol level.

Analysis on the clustering of risk factors indicates that Insulin, ALT, GGT, HDL cholesterol, high-sensitivity CRP, and blood pressure were significantly associated with overweight and obesity in adolescent boys. In adolescent girls, insulin, high-density lipoprotein cholesterol, and high-sensitivity C-reactive protein were significantly associated with overweight and obesity.

Previous studies suggested that the presence of more than 1 risk factor in childhood presents an increased risk of cardiovascular disease in adulthood.  Identifying adolescents at risk for long-term morbidity and offering early intervention may improve long-term outcomes.

Source:
Elizabeth Denney-Wilson et al (2008); Arch Pediatr Adolesc Med. 162(6):566-573

Vitamin D deficiency rickets has been reemerging as a public health problem in some developed and developing countries. Persistent severe vitamin D deficiency causes rickets in children and osteomalacia in adults, whereas mild vitamin D deficiency may also be associated with hyperparathyroidism and increased bone turnover.

A cross-sectional study by researchers in Australia, China, and Malaysia investigated the influence of low-vitamin D status on bone mass, bone turnover, and muscle strength in 301 healthy Chinese adolescent girls in Beijing, China.  The researchers measured the Blood plasma 25-hydroxyvitamin D [25(OH)D], the plasma and urine biomarkers of bone turnover; and the bone mineral content (BMC) and density and bone area for the whole body and the distal and proximal forearm

Vitamin D deficiency was defined as a serum 25(OH)D concentration of <=50 nmol/L.  Severe
Deficiency was defined as <25 nmol/L.  58% of the adolescent girls were vitamin D deficient and 31% were severely deficient.

The study results showed that girls with adequate vitamin D status had higher size-adjusted BMC for the whole body, distal forearm, and proximal forearm than those with poorer vitamin D status.  Similar results were also found for handgrip muscle strength.

Girls with adequate vitamin D status had significantly lower concentrations of biomarkers for bone resorption compared with those of the vitamin D-deficient girls, suggesting that low vitamin D status is associated with greater rates of bone remodeling.

Adolescent girls with adequate vitamin D status had significantly higher bone mass and muscle strength compared with those with poor vitamin D status. This may be attributed in part to a lower rate of bone remodeling with adequate vitamin D status.

These findings suggest that adequate vitamin D status during adolescence is important for optimizing bone mass, which may lead to higher peak bone mass at maturity. Poor vitamin D status also compromises forearm muscle strength.

In conclusion, adequate vitamin D status is important in enhancing muscle strength and in attaining higher peak bone mass. This effect on bone may in part be attributed to lower rates of bone remodeling when vitamin D status is adequate.

Source:
Leng Huat Foo et al. (2009) J. Nutr. 139: 1002–1007

Studies have demonstrated inverse relationships between diet quality and the common mental disorders in adults. However, little is known about such association in adolescents. Given that three quarters of lifetime psychiatric disorders will emerge in adolescence or early adulthood, a recent prospective study investigated the temporal relationships between diet quality and mental health and the associations between change in diet quality and change in psychological symptoms.

Researchers collected diet and mental health information from 3040 Australian adolescents aged 11–18 years at baseline in 2005–6 and followed up in 2007–8.  The study found that boys had significantly higher scores on the Unhealthy diet scale than girls and were also more active; and that improvements in diet quality were mirrored by improvements in mental health over the follow-up period, while deteriorating diet quality was associated with poorer psychological functioning.

The researchers hypothesized that diet quality influences the genesis and/or progression of depressive illnesses by modulating inflammatory, oxidative and/or neurotrophic factors.

Given that adequate nutrition is essential during periods of rapid physical development, and that the majority of mental health problems first manifest in adolescence and early adulthood, further intervention studies are now urgently required to test the effectiveness of preventing the common mental disorders through dietary modification.  For the parents, the foods available and provided to adolescents need to be receiving much greater attention.  Particular attention should be paid to creating environments that promote healthy eating in supporting adolescents to maintain good nutrition during a difficult life stage.

Source:
Jacka FN et al. (2011) A Prospective Study of Diet Quality and Mental Health in Adolescents; PLoS ONE 6(9): e24805. doi:10.1371/journal.pone.0024805