Toddlers' diets and the impact of nutrition on physical and psychological well-being were the focus of study days organised by The Learning Curve earlier this year.Linda Edmondsonreports from the Birmingham event, at which speakers discussed food and child development, nutrition and healthy growth, food, learning and behaviour, and the reality of what toddlers are eating
Feeding toddlers the right foods, in the right quantities for growth and well-being, is often a challenge for parents. At the 2011 regional study days organised by "The Learning Curve" and chaired by doctors Mark Porter and Hilary Jones, delegates learned that several mealtime behaviours are normal, if frustrating, aspects of child development. However, many eating habits are set in the second year of life, so it is important to encourage young children to eat a wide range of foods,for optimal nutrition and lifelong health.
Developmental stages in food acceptance/rejection
Some food behaviours are part of normal childdevelopment, explained
Dr Gillian Harris, Consultant Paediatric Psychologist at The Children's Hospital, Birmingham. She provided evidence-based advice, to help differentiate expected behaviours from those that could be associated with more serious psychological conditions.
Faddy (or fussy) eating* is a broad term that characterises:
_ Insufficient daily consumption of calories to maintain optimal growth
_ Refusal of the wide range of foods necessary for optimal nutrition.
Some faddy eaters reject specific foods because of their appearance or texture. Others exhibit variable acceptance patterns (eg: eating a food one day, but then refusing it). Dr Harris described key factors that may cause faddy eating habits to develop.
Textures and chewing
In the first six months, the tongue is prepared for a liquid swallow and the mouth is very sensory-sensitive; infants can cope easily with puréed food, but can often gag on small lumps in the foods given to them. At six to 10 months of age, babies need to develop oral motor skills, which they achieve through exposure to different textures at the appropriate time1. This process gradually desensitises the sides of the mouth, so during this phase:
_ Food play should be encouraged
_ Different textures should be introduced in carefully managed steps:
_ purées _ mashes
_ lumps _ finger foods.
Finger foods with bite-and-dissolve qualities are easy to cope with (which is why savoury snacks and chocolate buttons are popular with weaning babies!). However, parents also need to persevere at this stage, by repeatedly offering tastes and textures, even those that provoke gagging and retching in their babies. Avoiding lumpy solids may lead to problems with food acceptance in later childhood2.
Sensory-sensitive people exhibit heightened awareness of experiences involving noise, light, smell or touch, in addition to texture and taste. Such attributes may have a hereditary element: in some families, siblings or older relatives exhibit similar behaviours. Again, explained Dr Harris, some degree of sensory sensitivity, manifesting as a lifelong avoidance of certain tastes and textures, is perfectly normal. Similarly, a toddler who gives up on the main course but then asks for pudding is exhibiting normal sensorysensitive behaviour. He has had enough of one taste or texture, and wants something different. This is also completely normal. But sensory sensitivity can develop into more serious manifestations of food rejection if infants are not fully exposed to different textures at weaning.
Neophobia and avoidance
Neophobia describes the rejection of new foods, or foods previously accepted. It emerges at 12 to18 months of age, affects most children and is a normal survival behaviour, said Dr Harris. In pre-civilised times, toddlers need mechanisms to avoid unfamiliar (ie: potentially toxic) foods.
Nowadays, neophobic children are those who notice the fine details at mealtimes. They reject toast of the wrong shape and colour, or refuse a familiar dish presented differently, or a favoured food in new packaging. This is why fast-food restaurants are popular with children: they provide "dry" foods that are uniform in shape, neutral in colour, and often served in exactly the same way. Generally, neophobia resolves gradually. As children learn the social rules of eating, they begin to eat foods prepared in different ways (eg: both jacket and boiled potatoes), and few remain neophobic by five years of age3. However, symptoms persist in some children - now described as avoidant or restrictive eaters - for reasons including: _ Missing the critical window of mouth desensitisation, due to delayed/incomplete weaning
_ Having an inherent pattern of sensory sensitivity or selective eating (often reported in other relatives). Many avoidant eaters are boys, many dislike eating in public environments (such as school cafeterias), and many - but not all - are on the autistic spectrum. Indeed, 70 per cent of the children with avoidant eating behaviours who are under Dr Harris' care also have autistic spectrum disorder. They find it difficult to overcome the attention to sensory detail and are often unable to imitate the social food-related behaviours exhibited by those around them. Neophobic behaviours can be managed in most children by offering small quantities of new foods frequently, over a long time period: eventually, a preference may develop. Dr Harris did not advocate "hiding" new foods within familiar dishes: neophobic children consider any unfamiliar items on their plates as contaminants.
The social rules of eating
At four to five years of age, or possibly earlier, explained Dr Harris, children learn to attend to extrinsic cues to appetite rather than intrinsic cues. For example, they learn to eat when others are eating, or to empty their plate even if they are not hungry, and eventually to comfort eat. Imitating others' food behaviours can help to improve a child's acceptance of food, as well as their nutritional intake. However, there is a fine line, cautioned Dr Harris. Training children to ignore internal signals of satiety, and encouraging comfort eating, may contribute to the rising levels of obesity.
"We have an ideal weight and we take in enough to keep us at that weight," Dr Harris explained. Adults regulate their nutritional intake - from meal to meal or day to day - according to a "set point" weight. This mechanism is apparent from early infancy: breast-fed babies need to be able to regulate their intake.
However, appetite regulation manifests slightly differently in toddlers who eat well one day (or one week), but poorly the next. But again, this is often normal behaviour. Such children have well-regulated appetites in which growth hormone secretion, growth velocity and energy requirements dictate hunger levels; they are not affected by social or conditioning influences. Over time, children gradually learn the energy loading of the usual foods that they consume. Their hunger is then satiated by particular calorie loads at specific mealtimes, and the appetite-regulation pattern seen in adults is set.
Developing food preferences
All food preferences are learned through acceptance:
_ Humans have innate preferences for specific tastes, not specific foods
_ Preferences may begin in utero or during breastfeeding4
_ At birth, infants prefer sweet tastes and fatty textures
_ Aversions to bitter or sour tastes occur because of their association with toxicity.
The first objective of weaning is to introducing new tastes, so that babies develop their personal food preferences. Very small quantities are usually sufficient to induce a preference:
_ Fewer exposures are necessary in babies who begin weaning at 17-26 weeks, compared with children who try the tastes later
_ Unless there is a family history of atopy, babies should receive a wide a range of new tastes as soon as weaning begins, especially if this is at 26 weeks
_ Only a teaspoonful needs to be given, per exposure
_ With parental persistence, children soon learn to tolerate bitter or sour tastes.
Parents should offer all the family foods, including repeated exposures to tastes that are initially refused, to increase the likelihood that children have varied, balanced diets in later life. Babies who taste different vegetables, with a daily change, are likely to readily accept new vegetables in the long term5.
_ Higher fruit/vegetable intakes are observed at seven years in children weaned on these foods6
_ It is pointless to introduce foods that the family rarely consumes, or actively dislikes.
With support and reassurance, many parental concerns about food avoidance can be allayed (Box 1):
_ Parents should not carry the blame for food avoidance behaviours in their child
_ Faddiness is often part of normal development
_ Ensuring the child has a satisfactory energy intake is the priority: variety is secondary. Where there are more chronic concerns in children with substantial food refusal behaviours, with perseverance, careful management and specialist referral (if necessary), many children can eventually learn to accept a wider variety of foods.
Currently there is no standard definition for extreme (fussy) eating. This makes it difficult to compare research findings and standardise clinical practice. However, an agreed definition should be included in the Diagnostic and Statistical Manual of Mental Disorders V (to be published by the American Psychiatric Association in 2013).
1. Gisel EG. Effect of food texture on the development of chewing of children between six months and two years of age. Dev Med Child Neurol 1991; 33(1): 69-79
2. Coulthard H, Harris G, Emmett P. Delayed introduction of lumpy foods to children during the complementary feeding period affects child's food acceptance and feeding at 7 years of age. Matern Child Nutr 2009; 5(1): 75-85
3. Birch LL, McPhee L, Shoba BC et al. What kind of exposure reduces children's food neophobia? Looking vs. tasting. Appetite 1987; 9(3): 171-178
4. Mennella JA, Jagnow CP, Beauchamp GK. Prenatal and postnatal flavor learning by human infants. Pediatrics 2001; 107(6): E88
5. Maier AS, Chabanet C, Schaal B et al. Breastfeeding and experience with variety early in weaning increase infants' acceptance of new foods for up to two months. Clin Nutr 2008; 27(6): 849-857
6. Coulthard H, Harris G, Emmett P. Long-term consequences of early fruit and vegetable feeding practices in the United Kingdom. Public Health Nutr 2010; 13(12): 2044-2051
Infant and toddler forum factsheet 1.7. Toddler meals. How much do they need? Available at http://www.infantandtoddler forum.org/article_17+Toddler+meals+how+much+do+they+need _id-558.html. Accessed 11 April 2011.
Promoting healthy growth through nutritionJohanna Hignett, a Nutritionist, Registered Dietitian and mother of two young children from Sutton in Surrey described how nutrition affects growth. Growth is the process by which the body lengthens and broadens, and regular assessment of growth is a key tool for health professionals in assessing child health. If growth (ie: length/height, weight and head circumference) is being monitored appropriately and the plotting points follow the correct centiles line for the individual child, there is no issue. For most children, growth only becomes of concern when the measurements cross two centile lines, either up or down, explained Ms Hignett:
_ If a child has adequate nutrition, he can maintain his genetically determined growth velocity and achieve his growth potential
_ If his intake of energy or other key nutrients is restricted, growth may be affected.
Genetics and other physiological factors also have a major influence on linear growth rates. Growth hormone and thyroxine levels are critical for determining final height. In rare cases, hormone imbalances may affect growth and children need specialist referral if such conditions are suspected. However, most children who show growth faltering have issues with food intake. Regular monitoring is also important for early identification of excessive weight gain. Early recognition of a problem may help to avoid later development of overweight and obesity. One concern, explained Ms Hignett, is that our normal expectations have changed in recent years: our society is now accustomed to seeing people of higher weight, therefore we are less likely to notice the development of overweight children.
Common nutritional deficiencies
Ms Hignett presented data to illustrate the widespread deficiencies in key nutrients that are apparent in UK children (Figure 1). Many of these nutrients are important for growth, in addition to specific aspects of health (Table 1).
Vitamin DVitamin D deficiency is of growing concern in the UK. Vitamin D is unique in that it can be manufactured in the body by the action of sunlight on the skin: indeed, it is more correct to consider vitamin D as a hormone rather than a vitamin, because of this synthesis. Vitamin D deficiency is becoming a problem because of the tendency to "cover up" (to reduce the risk of skin damage, or to comply with cultural or traditional practices). In addition, the strength of winter sunlight anywhere north of the English Midlands or mid-Wales is likely to be insufficient to trigger vitamin D production in exposed skin. By way of recommendation, from April to September, 10 to 15 minutes' exposure of the lower arms to sunlight after 3pm should produce adequate vitamin D, without the risk of skin damage, in children and adults. Vitamin D is added to some foods including margarines, some breakfast cereals, infant formula and follow-on formula. However, the Department of Health recommends vitamin drops that contain vitamin D from six months of age, for breast-fed babies or those receiving < 500ml of infant or follow-on formula per day. These drops are recommended up to five years of age.
Iron Iron deficiency is one of the most common nutrient deficiencies found in toddlers in the UK for several reasons:
_ Rapid growth creates high demand for iron
_ A baby is born with sufficient iron reserves for 6 months; after then, iron needs to be provided by the diet
_ Iron in breast milk is efficiently absorbed, but older breast-fed babies need other dietary sources to maintain a good iron status
_ Faddiness or neophobia may reduce the nutritional intake of iron-rich foods
_ A nutritionally poor diet may permit growth, but mask iron (and other) deficiencies.
Upping the iron level
The best source of iron in the diet is red meat (haem iron), but iron is also found in green leafy vegetables, egg yolk, beans and pulses and fortified foods such as breakfast cereals, flour and infant and follow-on formula (non-haem iron). Vitamin C enhances iron absorption, so serving breakfast cereal as a dry snack with diluted fruit juice, or meat with green vegetables are good strategies to maximise iron uptake. Iron-fortified foods can be useful for preventing iron deficiency, and the recent SACN report provided guidance on increasing iron-rich foods and the use of supplementation, outlined Ms Hignett. Research has shown that using iron-supplemented formula until 18 months of age, rather than introducing cows' milk, prevented iron deficiency and reduced the decline in psychomotor development, in inner-city children5. Practical advice to enhance iron levels:
_ Encourage a varied diet (meat, pulses, green vegetables)
_ Monitor reliance on cows' milk, which is low in iron (and because excessive intake can reduce consumption of other foods)
_ Give iron-fortified foods (e.g. certain breakfast cereals, follow-on formula)
_ Encourage a good intake of fresh fruit and vegetables.
If a child does not eat red meat, check that the child regularly consumes alternative dietary sources of iron. However, as iron requirements can vary between individuals and the body can adapt to low iron intakes, having a low iron intake does not automatically lead to iron deficiency anaemia, or restricted growth, Ms Hignett added. She recommends the regular monitoring of children who appear to have low iron intakes.
What to watch for
Energy requirements - to achieve optimum growth and nutrition, toddlers need a variety of foods. Their diets should contain adequate energy - but not too much.
At two years of age, the daily requirement for boys is around 1,190 Kcal, and for girls 1,130 Kcal. At three, the levels increase to approximately 1,380 Kcal and 1,320 Kcal, respectively. Faltering growth can occur in children across the social spectrum. Key to encouraging growth is dietary energy. It is worth noting that adult style "healthy" diets (high-fibre, low-fat) are unsuitable for young children because they rarely contain enough calories for adequate growth and nutrition.
_ If there are signs of growth faltering, first ensure that the child is consuming enough calories
_ The nutritional quality and variety within the diet can then be addressed Little and often - young children need appropriate foods, little-and-often: daily intakes often improve with a routine of three small meals plus two snacks, rather than grazing or eating three larger meals.
_ Find the right level of energy intake for a child, without pushing her into being overweight
_ Most young children self-regulate their appetite
Getting the right balance
We eat food, not nutrients, and mealtimes should be a positive experience, Ms Hignett reminded delegates. It is important that children learn to consume (and enjoy) a variety of foods, particularly if they have any dietary restrictions. Although a vegetarian diet is adequate for child growth, vegan diets are not recommended for toddlers unless the parents can ensure that the full range of nutrients required for optimum growth and development is being offered. Fortified foods and supplements can be useful for children at risk of nutritional deficiencies.
1. Gregory JR, Collins DL, Davies PSW et al. National Diet and Nutrition Survey: children aged 11⁄2 to 41⁄2 years. Volume 1: Report of the diet and nutrition survey London: HMSO, 1995
2. Morgan J. Nutrition for toddlers: the foundation for good health- -1. toddlers' nutritional needs: what are they and are they being met? J Fam Health Care 2005; 15(3): 85-88 3. Morgan J. Nutrition for toddlers: the foundation for good health- -2. Current problems and ways to overcome them. J Fam Health Care 2005; 15(3): 85-88 4. SACN Iron and Health Report. Available at: http://www.sacn.gov.uk/reports_position_statements/reports/sacn_ir on_and_health_report.html. 'Accessed 15 May 2011' 5. Williams J, Wolff A, Daly A et al. Iron supplemented formula milk related to reduction in psychomotor decline in infants from inner city areas: randomised study. BMJ. 1999 Mar 13;318(7185):693-697. Erratum in: BMJ 2000 Jul 1;321(7252):23
Further informationwww.littlepeoplesplates.co.uk contains practical advice and information to support health care professionals and parents to optimise toddlers' diets
Nutrition, Behaviour, Learning and MoodDr Alex Richardson, (Centre for Evidence-Based Intervention, University of Oxford, and Food And Behaviour Research) characterised the invisible damage of poor nutrition. "Any diet bad for the body is also bad for the brain", she reminded delegates1. The gut shares many chemical neurotransmitters with the brain - serotonin, for example, which is crucial for gut motility as well as mood regulation.
Dr Richardson - who has a background spanning education, and food and behaviour research - discussed the overlap between nutrition and attention deficit hyperactivity disorder (ADHD), dyslexia, dyspraxia and autistic spectrum disorder. One in five primary school children has a behavioural or learning difficulty, but she challenged the idea that such conditions have a purely genetic basis: "Environmental factors play a part, nutrition in particular because it shapes and influences gene expression - it's at the interface of nature versus nurture". The increasing prevalence of these disorders could also be linked to environmental toxins and poor nutrition.
Changing methods of food production and consumption over the 20th century created the "Western" diets, now commonly followed in the developed world. Such diets rely on refined carbohydrates, artificially saturated fats, and often have high levels of salt, sugar and artificial additives. These foods are evolutionarily novel, and potentially pathological2, thus contributing to the increasing incidence of people with the metabolic syndrome, "type B2" malnutrition (ie: overfed but undernourished), immune-system dysfunction and dietrelated psychological disorders.
Blood sugar regulation
Contrary to popular belief, there is no direct and simple connection between sugar consumption and hyperactivity or concentration problems: in fact, sugary foods or drinks can actually improve concentration in the very short-term if blood glucose levels have fallen too low - which helps to explain their appeal. However, diets that are high in refined carbohydrates have negative consequences on metabolism:
_ Rapidly fluctuating glycaemic peaks and troughs affect attention, memory, mood and insulin regulation
_ Impaired glucose tolerance is common in people with ADHD and young offenders
_ Micronutrient deficiencies are more likely to occur in people who regularly consume energy-dense, nutritionally poor diets, because metabolising refined foods creates extra demands on some vitamins and minerals:
_ To unlock the energy from one molecule of glucose requires 37 molecules of magnesium
_ Diets high in sugar and the wrong types of fat (see below) can stunt brain development and connectivity.
Dr Richardson characterised the pitfalls of the sugar "rush". Starting the day with a quick sugar release (eg: a can of sugary drink and a chocolate bar) creates a rapid increase in blood sugar. Insulin is then secreted in high quantities, to convert the simple sugar into energy, but the rapidity of this process results in a hypoglycaemic crash, characterised by poor concentration, low mood, aggression or irritability. She contrasted this with the sugar "hush"'. When breakfast includes foods such as porridge, a boiled egg or wholegrain toast, the energy from complex carbohydrates is broken down and released more slowly, insulin is secreted in a more controlled manner and fluctuations in glycaemia, hunger and mood are less likely to occur.
Although the WHO advises that a maximum of 10 per cent of one's daily calorific intake should come from simple sugars, levels in the Western diet routinely exceed 30 per cent. Animal studies indicate that diets high in simple sugars are addictive, added Dr Richardson. Withdrawal symptoms were observed when animals were switched from high to low-sugar diets3, and in another study, opioid-like effects of refined sugar were also observed in "reward" areas of the rat brain4.
In a year-long study involving over 3,000 imprisoned young offenders, marked improvements in behaviour occurred when sugary refined carbohydrate snacks were replaced with less-refined, lower-sugar alternatives. These improvements included:
_ A 21 per cent reduction in anti-social behaviour
_ A 100 per cent reduction in suicide
_ A 25 per cent reduction in assaults
_ A 75 per cent reduction in restraint use5.
Micronutrient deficiencies / imbalances
Although many people's diets fail to provide the minimal recommended levels of key nutrients, Dr Richardson acknowledged that individuals' requirements vary greatly. In some people, low consumption does not lead to deficiency. She also emphasised that nutritional supplements are only likely to improve ability or behaviour in subgroups of children with poor nutritional status. In such children, supplementation improved nonverbal intelligence in 10 of 13 randomised controlled trials6. However, supplementation does not have statistically significant benefits in heterogeneous study populations (which include children with good nutritional status, or those with no prior behavioural or learning issues). Characterising the most common nutrient deficiencies in the UK, Dr Richardson described the link between vitamin A deficiency (which affects about 10 per cent of children) and visual impairments or certain immune system dysfunctions. She also emphasised the marked, negative, effect of iron deficiency on brain function. Poor iron intake and status have been linked to ADHD development, and deficiency in early life may have permanent neurological or psychological effects, she explained, although further research is required.
Results from national diet and nutrition surveys show that almost 50 per cent of teenage girls have sub-optimal iron intakes. In addition, zinc deficiency affects around 10 per cent of all children, and can contribute to poor appetite and anorexia as well as having been linked with a wide range of psychological disorders. Magnesium deficiency is associated with anxiety and potassium deficiency has been linked with depression and fatigue, she added.
The right fat balance
Getting the right balance of dietary fats "is probably the single most important thing that anyone can do to improve their diet, and their physical and mental health", Dr Richardson emphasised, focusing particularly on the essential fatty acids (EFA) omega 3 and omega 6 polyunsaturates. EFAs, which are found in certain natural vegetable (and all fish) oils, have profound effects on brain development and functioning, as well as on immunesystem function, hormone balance and blood flow. The EFAs are special polyunsaturated fats that have to be obtained from dietary sources:
_ The simplest EFAs (the omega-3 alpha-linoleic acid and the omega-6 linoleic acid) are found in plant-derived foods (green vegetables, nuts, seeds and oils from these), and can in theory be converted to the longer-chain, highly unsaturated fatty acids (HUFA) of the same series - crucial for brain function and cellular development
_ However, conversion is inefficient - and is also blocked by factors including excessive alcohol consumption, smoking, diabetes and certain allergies
_ For these reasons, it is more efficient to consume foods that are good direct sources of HUFA. Meat, eggs and dairy products are good sources of the omega-6 HUFA, while fish and seafood are the only natural sources of the omega-3 HUFA.
The rise of the Western diet has changed the balance of fat intake. One reason for this that processed foods are often fried or baked in saturated fats or hydrogenated vegetable oils. The latter can contain artificially created trans fats, see Figure 2), which have no known nutritional benefits and many health risks, added Dr Richardson. Trans fats also compete with omega-3 and omega-6 fatty acids, and block their conversion into HUFA.
The ratio of omega 6 to omega 3 fatty-acid consumption is particularly important, she explained. In pre-industrial times, this ratio was approximately 3:1 but it is now > 15:1 (sometimes 100:1). Western diets usually contain high levels of omega 6, because of high consumption of:
_ Short-chain linolenic acid (LA) in vegetable oils and nuts
_ HUFAs including arachidonic acid (AA) and dihomo--linolenic acid (in meat, eggs, and dairy products).
The imbalance between omega 6 and 3 affects cell signalling, cellular growth and connectivity in the brain, and is implicated in the development of mental health disorders. Simply swapping a few meat, dairy and refined foods for fish, seafood, green vegetables, nuts and seeds helps to redress the balance.
The simplest form of omega 3 (the short-chain form) is -linolenic acid (ALA), found in green leafy vegetables, walnuts, flaxseed and rapeseed oil. However, it is extremely important for the diet to include long-chain omega 3 fatty acids (in fish and seafood; Figure 3), because short-chain omega 3 fatty acids are not well converted into the key HUFA - particularly docosahexaenoic acid (DHA), which is important for brain structure and functioning:
_ Diets that contain no fish provide little or no preformed long-chain omega 3
_ Supplements with ALA do not redress this balance7
_ In a large UK birth cohort study (ALSPAC), women who ate no fish (or restricted their intake to current government guidelines during pregnancy) had children with poorer developmental outcomes than children whose mothers who ate more fish8. The correct balance between omega 6 and omega 3 is also important because these fats are used as raw materials to produce numerous substances that control a wide range of physiological functions. Broadly speaking:
_ Omega 6-derived substances are proinflammatory and prothrombotic
_ Omega 3 substances are anti-inflammatory and anti-thrombotic.
Omega 3 supplementation
Pregnancy, infancy and toddlerhood are critical periods when omega 3 must be provided in the diet. "Findings from the ALSPAC study show that the benefits of longchain omega 3 fatty acids outweigh the potential risks of consuming higher levels of oily fish during pregnancy", stressed Dr Richardson. In infancy, DHA - which is acquired in utero and found in breast milk - is essential for visual acuity, and some studies show benefits for cognitive development - particularly in premature or low-birthweight infants. Randomised controlled trials have already shown significant benefits of omega 3 supplementation for depression and bipolar disorder in affected adults. The American Psychiatric Association now recommends > 1g per day of eicosapentaenoic acid (EPA) plus DHA as add-on treatment for mood disorders9, although results have been mixed in heterogeneous populations10. A pilot study also found that fish oils reduced symptoms of depression in affected children11.
A daily intake of 500 mg EPA+DHA is recommended by scientists to maintain cardiovascular health. Studies of EPA+DHA supplementation for behaviour and learning improvement are generally positive for children with dyslexia, dyspraxia and ADHD-type symptoms12, although in clinical populations of children with formal diagnoses of ADHD, findings are less conclusive, with any benefits restricted to particular subgroups13,14. Dr Richardson's own research identified significant improvements in reading and spelling when EPA+DHA supplements were given to under-achieving children aged five-12 years with difficulties in motor co-ordination (dyspraxia or developmental co-ordination disorder).
Concentration, behaviour and working memory improvements were also observed in children given active treatment compared with placebo, in this study15. "No one intervention will help all children," commented Dr Richardson, emphasising the need to identify the subgroups who respond well to specific dietary improvements. "But there is no downside to giving children a better diet."
Toddler diets: the reality
Research undertaken by Danone Baby Nutrition (DBN), in collaboration with Dr Alison Lennox (Medical Research Council, Cambridge) and Dr Claire Robertson (from University of Westminster, London), indicates that little has changed with regard to the quality of toddler diets in the UK, over the past 20 years. Dr Janet Warren, Registered Dietitian and Head of Medical Affairs at DBN, who previously worked at the MRC, presented key findings from the survey.
Few improvements in 20 years
The DBN Dietary Nutrition Survey data indicate that today's 12-24 month-old children generally receive adequate daily nutrition, but concerns remain about the quality of what they eat. In particular, very young toddlers frequently consume convenience foods. Consequently, daily intakes of salt and saturated fat remain high, and consumption of fruits and vegetables remain low, for some children.
In the DBN survey, data were collected from 220 extensive food diaries in a nationally representative sample of children, aged 12-24 months. The diaries were completed by the children's mothers over a consecutive four-day period in July 2009. The results show that:
_ Current nutritional intakes seem very close to those observed in the large ALSPAC and NDNS cohorts in the early 1990s1,2.
Indicators of poor diet
In particular, the DBN survey identified potential indicators of poor dietary quality in these young toddlers (Figure 4). These are warning signs, for which health care professionals should be alert:
_ ≥1 unhealthy snack (chocolate, crisps, sweets) consumption, every day
_ ≥1 "convenience" food (fast food, pizza, Indian or Chinese take-away, composite ready meal) over a four-day period
_ <8 servings** of fruit or vegetables across a four-day period (<2 servings per day).
Iron in the 21st century diet
The average daily iron intake across the DBN study cohort (Figure 5), at 5.6 mg (range 2.1-14.33 mg), was lower than the RNI for one to three-year-old children, which is 6.9 mg/day. Consistent with other speakers, Dr Warren cautioned that children who consume less than the RNI are not necessarily anaemic, but it is of note that: 79 per cent of the diets did not meet the RNI for iron 17 per cent of the children had intakes less than the lower RNI and so were at risk of iron deficiency anaemia.
1. Northern S. A rotten way to feed the children. TES 16 April 2004. Available at: http://www.tes.co.uk/article.aspx?storycode=393454. (Accessed 15 May 2011)
2. Cordain L, Eaton SB, Sebastian A et al. Origins and evolution of the Western diet: health implications for the 21st century. Am J Clin Nutr 2005; 81(2): 341-354
3. Colantuoni C, Rada P, McCarthy J et al. Evidence that intermittent, excessive sugar intake causes endogenous opioid dependence. Obes Res 2002; 10(6): 478-488
4. Spangler R, Wittkowski KM, Goddard NL et al. Opiate-like effects of sugar on gene expression in reward areas of the rat brain. Brain Res Mol Brain Res 2004; 124(2): 134-142
5. Schoenthaler, S. The Northern California diet-behavior program: An empirical examination of 3,000 incarcerated juveniles in Stanislaus County Juvenile Hall. J Int J Biosocial Res 1983; 5(2): 99-106
6. Benton D. Micro-nutrient supplementation and the intelligence of children. Neuroscience and Biobehavioural Reviews 2001; 25(4): 297-309
7. Brenna JT, Salem N Jr, Sinclair AJ et al. alpha-Linolenic acid supplementation and conversion to n-3 long-chain polyunsaturated fatty acids in humans. Prostaglandins Leukot Essent Fatty Acids 2009; 80(2-3): 85-91
9. Freeman MP, Hibbeln JR, Wisner KL et al. Omega-3 fatty acids: evidence basis for treatment and future research in psychiatry. J Clin Psychiatry 2006; 67(12): 1954-1967. Erratum in: J Clin Psychiatry 2007; 68(2): 338
10. Appleton KM, Hayward RC, Gunnell D et al. Effects of n-3 longchain polyunsaturated fatty acids on depressed mood: systematic review of published trials. Am J Clin Nutr 2006; 84(6): 1308-1316
11. Nemets H, Nemets B, Apter A et al. Omega-3 treatment of childhood depression: a controlled, double-blind pilot study. Am J Psychiatry 2006; 163(6): 1098-100
12. Vaisman N, Kaysar N, Zaruk-Adasha Y et al. Correlation between changes in blood fatty acid composition and visual sustained attention performance in children with inattention: effect of dietary n-3 fatty acids containing phospholipids. Am J Clin Nutr 2008; 87(5): 1170-1180
13. Johnson M, Ostlund S, Frannson G et al. Omega-3/omega-6 fatty acids for attention deficit hyperactivity disorder: a randomized placebo-controlled trial in children and adolescents. J Atten Disord 2009; 12(5): 394-401
14. Matsudaira T. Attention deficit disorders-drugs or nutrition? Nutr Health 2007; 19(1-2): 57-60
15. Richardson A, Montgomery P. The Oxford-Durham study: a randomized, controlled trial of dietary supplementation with fatty acids in children with developmental coordination disorder. Pediatrics 2005; 115(5): 1360-1366
Food And Behaviour Research - www.fabresearch.org Richardson A. They are what you feed them. ISBN-10: 0007182252; ISBN-13: 978-0007182251.
A serving of fruit or vegetable was not necessarily as large as a portion: one or two peas would count as a serving.
Toddlers who regularly had iron-supplemented breakfast cereals had better iron RNI intakes than other toddlers (and Dr Warren emphasised their value as a snack at any time during the day). However the 21 per cent of children who met their daily iron requirements also regularly consumed iron-fortified bread and follow-on milk or growing up milk, Dr Warren indicated.
Poor nutrition crosses social classes
In both the DND survey and in a 2010 telephone poll of toddlers' diets (Little People's Plates, http://www.littlepeoplesplates.co.uk/), poor quality diets were seen in children across all social strata. Low-, middle- and high-income families were reliant on convenience foods; they just purchased them from different supermarkets. "It is impossible to make sweeping generalisations about the quality of toddler diets," stated Dr Warren.
The Little People's Plates survey involved over 1,000 mothers of toddlers. Among its findings:
_ 42 per cent of mothers felt that they lacked information on nutrition
_ 81 per cent of mothers offered their toddler pre-prepared food designed for adults
_ 65 per cent of parents never cooked meals from scratch
_ 15 per cent of toddlers were eating adult ready-meals or take-aways for most meals.
Why food choices matter in toddlerhood
There are individual variations, but role modelling and parental style are critical for reinforcing good feeding habits, because young children mimic certain behaviours.
For example, they will be more likely to eat the foods that their parents consume, and to have good eating habits once the faddiness of toddlerhood is over, if they tried foods during late infancy/early toddlerhood:
_ Eating habits and food preferences continue to develop from 12 months
_ Bad habits can be changed in later life, but this is not easily achieved
_ Origins of cardiovascular disease may start in early childhood
_ Establishing good eating habits in toddlerhood is particularly important.
Excessive cows' milk consumption is a common cause of poor diet, may cause problems and Dr Warren encouraged health care professionals to ask all parents about their child's daily intake because this is a habit that is quite easily broken. Outwardly, children who regularly consume >750-1,000ml cows' milk per day may appear to be thriving, but may be at high risk of micronutrient deficiencies (especially iron deficiency).
Nutrition studies in progress
Dr Warren outlined contemporary studies that are collecting data on nutrition.
The National Diet and Nutrition Survey is a four-year rolling programme funded by the Department of the Health (DH) and the Food Standards Agency (FSA) that has been collecting information on food consumption annually since 2008/09. The programme adds 1,000 new subjects each year (500 children and 500 adults from 1.5 years of age upwards).
Very early findings from this survey suggest that in young children, fruit and vegetable intakes are improving, and that sugar intakes are starting to decline, although Dr Warren cautioned that the numbers are too small to draw firm conclusions.
The DH and FSA have also commissioned a national cross-sectional survey of dietary intakes in children aged four to 18 months. This work is also being led by MRC Human Nutrition Research, Cambridge. "These are exciting times for those interested in the diet of toddlers in the UK today," she explained.
Medical Writer, Stourport-on-Severn
The Learning Curve is an initiative to provide study days for health professionals and is supported by an educational grant from Danone Baby Nutrition. Linda Edmondson received a fee for writing this report from an educational grant provided to Journal of Family Health Care by Danone Baby Nutrition.