Ensuring adequate nutrition of the littlest ones means providing basic vitamins and minerals, as well as amping up foods with functional alternatives. Todd Runestad researches the best options on the table
Over the past three decades, the number of American children who are overweight has more than doubled among 2- to 5-year-olds and more than tripled among 6- to 11-year-olds.1 The National Health and Nutrition Examination Survey (NHANES 1999) says one out of four American adolescents between the ages of 12 and 19 is overweight, or at risk of being overweight — an increase of nearly 20 per cent since NHANES III (1988-1994).2
Adult-onset diabetes, which is clearly linked to obesity, is no longer an accepted term because it is beginning in childhood. To top it off, a majority of children on Western diets eat too much fat, sugar, salt and excess calories and too little of the nutrients to help young bodies grow strong.
As bad as sedentary lifestyles and soda machines in schools3 are, fad diets, which influence girls much more than boys, tend to affect more than weight alone. A recent study found that middle school and high school girls who used unhealthful weight-control behaviours had significantly lower intakes of fruits and vegetables; grains; calcium; iron; vitamins A, C and B6; folate; and zinc. In contrast, no sector of boys had poorer dietary intakes whether or not they were dieting or consciously eating better.4
The course of pregnancy, childbirth and lactation as well as human milk composition are influenced by the intake of foods and micronutrients including iron, zinc, iodine and polyunsaturated fatty acids. Basic nutrition demands, at the very least, that children consume calcium and iron at higher levels. Of note, a handful of functional ingredients demonstrate great efficacy in improving various health parameters in children — among them omega-3 fatty acids, prebiotic fibres and probiotics.
There is perhaps no other vitamin or mineral that has such profound long-term health implications as calcium. Adequate calcium intake in childhood and adolescence can do more than anything to prevent osteoporosis later in life.
Even more compelling, increased calcium intake in later years may not reduce the accelerated risk of osteoporosis resulting from inadequate calcium intake during childhood and adolescence.5 An adequate provision of nutrients that composes the bone matrix and regulates bone metabolism should be provided from birth in order to achieve maximal bone mass. Peak bone mass, which is obtained during childhood and adolescent growth, is a key determinant of the lifetime risk of osteoporosis and bone fracture.6 Retrospective studies in adults suggest that childhood calcium intake is associated with risk of later osteoporosis and attendant bone breakage.7 Indeed, one study found low milk intake during childhood was associated with a two-fold greater risk of fracture among women aged 50 and older.8
A National Institutes of Health Consensus Development Conference discovered that about half of the children and adolescents consumed less than recommended intakes of calcium.9 Inadequate calcium intake during the pubertal growth spurt, in particular, may compromise an individual?s volumetric bone density and predispose children to bone fragility fractures.10
Calcium and phosphorus are the most common minerals of the human body. Both of these minerals depend on vitamin D for absorption.11 Phosphorus content in breast milk can maintain the optimal calcium-to-phosphorus ratio of 2:1. Prolonged breast-feeding without additional calcium and phosphorus may result in reduced bone mineralization.
Bone mineral consists of calcium phosphate, and high-dose calcium supplements that consist of the carbonate or citrate salts may bind food phosphorus, making it unavailable for absorption. A calcium phosphate supplement may be preferable to the usual carbonate or citrate salts because its phosphate serves to spare food phosphorus.12
Of note to researchers, the minimisation of fracture risk would be the ideal functional outcome on which to evaluate lifetime calcium intakes, but other indicators such as bone mass measurements or maximal calcium retention are usually used instead.13
Finally, although the primary focus of calcium is on bone health, a recent two-year pilot study of 59 9-year-old girls found calcium-rich diets improved overall nutrient intake. The calcium-rich group, whose average intake was 1,656mg/day, also significantly increased their intake of protein, vitamins A and D, phosphorus, potassium and magnesium, compared to those on a normal diet, which averaged 961mg/day.14
One of the most common nutritional disorders during infancy is iron-deficiency anaemia, which is routinely screened for through blood tests of haemoglobin. Solid foods are usually introduced around four to six months of age, particularly a single-grain, iron-fortified cereal such as rice cereal, to help prevent iron-deficiency anaemia.
Iron deficiency may cause lower mental and motor test scores in infants, yet these adverse effects can be improved by iron therapy.15 A newly published, prospective, single-blind, controlled clinical intervention study of 108 children aged 6 to 30 months assessed this hypothesis. The 37 children with iron-deficiency anaemia and about half of those with nonanaemic iron deficiency were treated with oral iron for three months. After treatment, lower mental development test scores were no longer observed among the groups whose anaemia and iron deficiency were also corrected.16 Previous studies correlate these findings. However, significantly lower mental and motor test scores have been shown to persist among the majority of initially anaemic infants who have more severe or chronic iron deficiency.17
More than iron alone, other micronutrients can have beneficial effects on motor development. A new double-blind trial of infants in India examined whether a weekly supplement of iron, zinc, iron and zinc together, or a multi comprised of 16 vitamins and minerals, would alter development and behaviour among six- and 12-month-olds. On motor development, the combination of iron and zinc, as well as the multi, worked best.18
Infant development, including visual acuity, and emergent cognitive functions are also aided by polyunsaturated fatty acids (PUFAs), in particular docosahexaenoic acid (DHA).19 PUFAs like DHA and EPA (eicosapentaenoic acid) are considered ?conditionally essential? because the body may be able to synthesise a small percentage of its needs from dietary sources of their precursor, alpha-linolenic acid. However, the conversion rate is less than 10 per cent, with one study measuring a conversion rate of only 3.8 per cent.20
PUFAs are gaining wide acceptance as ingredients in functional foods, especially in infant formulas. Preformed DHA is clearly a requirement because of the poor conversion rate of alpha-linolenic acid. Pregnancy and the first postnatal months are critical times for the growth and development of the human nervous system, processes for which adequate substrate supplies are essential.21
DHA and arachidonic acid (AA) are both present in breast milk. Studies show that while there are significant differences in plasma levels of PUFAs between breast-fed babies and those fed formula that does not contain supplemental PUFAs, this difference can be made up with formula using PUFAs.22,23
Between six and 12 months of age, blood levels of DHA in breast-fed infants typically decrease due to diminished maternal stores and as DHA-poor solid foods take the place of a diet based purely on mother?s milk. Because DHA has been found to be important in the early development of the visual system, studies have been undertaken to assess whether supplemental DHA can improve vision. One new randomised controlled clinical trial gave 25 six-month-olds 115mg/day DHA. At 12 months, the differences between the group that supplemented and a control group corresponded to one-and-a-half lines on the eye chart.24
The human brain experiences a growth spurt during the last trimester of pregnancy and the first postnatal months, with a large increase in the cerebral content of AA and DHA.
One recent long-term study in Norway assessed whether high intakes of cod liver oil during pregnancy would have effects on intelligence testing, problem solving and information processing among children four years later. A total of 341 pregnant women began supplementing at week 18 of pregnancy with 10mL cod liver oil until three months after delivery. The oil contained 1,183mg DHA and 803mg EPA. The children who were born to mothers who had taken cod liver oil during pregnancy and lactation scored higher on the Mental Processing Composite of the K-ABC at 4 years of age compared to children whose mothers had taken the corn oil placebo.25
Beyond intelligence, deficiencies of maternal DHA and postnatal deficiencies have been linked to behavioural problems and other neurological disorders.26 An assessment of 96 boys ages six to 12 years found that boys with lower levels of DHA had more behavioural problems such as hyperactivity, impulsivity, anxiety, temper tantrums and sleep tantrums, and were more likely to have attention-deficit hyperactivity disorder (ADHD).27
As demonstrated with omega-3s, the goal of functional ingredients developers within the infant nutrition field is to develop products that mimic the exquisite nutritional profile found in breast milk. The same goes with intestinal flora, which are important in the postnatal development of the immune system.
Researchers in Germany recently formulated a bovine milk formula with a prebiotic mixture from galacto-oligosaccharides and fructo-oligosaccharides. Their aim was to see if the intestinal flora of those taking it was similar to breast-fed infants. The mixture significantly increased the number of bifidobacteria and reduced the number of pathogens in term and preterm infants compared to a group of infants fed an unsupplemented formula.28
An Italian study demonstrated that oligosaccharides stimulate selectively the growth of bifidobacteria and lactobacilli in the intestine. Of note to formulators, researchers found no statistically significant difference between the group fed formula with 0.4g/dL oligosaccharides and the group fed formula with 0.8g/dL.29
A German study looked beyond immunity in 102 infants. Researchers tested an infant formula containing partially hydrolysed whey protein, modified vegetable oil with a high beta-palmitic acid content, prebiotic oligosaccharides and starch. After six weeks, girls in the formula group gained more weight and head circumference compared to the control group. However, these differences were not maintained throughout the 12-week study period.30
Fibre sources such as the prebiotic inulin lower insulin levels, so they give people more energy on a regular basis. For this reason they are seen as protecting against obesity.31 Indeed, fibre-rich ready-to-eat breakfast cereals have been used to promote weight loss when consumed as a portion-controlled meal replacement among 109 subjects.32
Children pick up breakfast-eating habits early on, so making sure they eat breakfast is a good idea, and breakfasts rich in fibre are doubly important. A review of 2,959 subjects on the US National Weight Control Registry found that eating breakfast is a characteristic common to successful weight-loss maintainers.33
Within days after birth, a baby?s bacteria-free gastrointestinal tract begins to get colonised with microflora. Researchers in Russia recently were able to determine the exact species composition of bifidobacteria and lactobacilli in healthy young children. The dominating species of bifidobacteria are B longum, B adolescentis and B infantis, while the most prevalent lactobacilli are L acidophilus and L rhamnosus. The researchers said these five strains hold good promise as the basis for complex probiotic preparations.34
This beneficial bacteria is involved in the digestion process and protects against infections. The clearest evidence to support supplementing with probiotics is for diarrhoea, whether from infections or antibiotic-induced.35 Around the world, diarrhoea causes more than three million child deaths every year.36 Because antibiotics are prescribed so often, particularly in the US against ear infections, doctors are increasingly recommending probiotics along with antibiotics. One probiotic strain in particular, Saccharomyces boulardii, has the best efficacy. In a recent study in Turkey, antibiotic-associated diarrhoea was seen in 42 of 222 patients (18.9 per cent) receiving an antibiotic alone, and in 14 of 244 patients (5.7 per cent) who received the antibiotic with S boulardii.37
In India, a probiotic milk formulation containing Bifidobacterium lactis HN019 as well as galacto-oligosaccharides for 12 months led to a significant reduction in dysentery as well as significantly reduced days with fever, severe illness and prevalence of ear infections. Interestingly, the supplementing group also had a 35 per cent reduction in iron-deficient children even though both groups received iso-caloric diets with the same iron content. Researchers believed this effect could be because of better absorption due to effects on gut flora.36
Finally, probiotics seem to prevent atopic dermatitis and other allergic conditions.38 One recent double-blind, placebo-controlled, crossover study used Lactobacillus rhamnosus and L reuteri for six weeks on 41 children with moderate and severe atopic dermatitis. The supplemented group experienced less severe eczema as well as decreased frequency of gastrointestinal symptoms.39
Fortified foods will play a great role in combating childhood obesity and enhancing baseline nutritional intake. In the US, the Institute of Medicine has now published a report, ?Preventing Childhood Obesity: Health in the Balance.? Putting particular emphasis on the need for food manufacturers to produce healthier, nutrient-rich foods, the report particularly notes the profit incentives that now exist for industry to develop low-calorie foods and drinks fortified with nutrients, and the opportunities that industry has to influence consumer choice via packaging, price and promotion.
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