We all know children need vitamins and minerals but just how much do they need? And if they're not eating enough are over-the-counter supplements the answer? Nutritionist Leanne Cooper writes.
Anyone who's tried to decipher the gobbledegook on the back of a food packet, will know it's a complicated world out there. And that's even before the battle of getting the appropriate daily servings of healthy food into our little ones. Take heart in the knowledge you're not alone.
Most of us know that a varied diet of whole foods is the best way to nourish our children and indeed ourselves. There is an extensive amount of research showing that the nutrients packaged in our food have a far more beneficial effect than synthetically made nutrients which you'd find in a bottle of supplements (although folic acid appears to be the exception, with a greater absorbency than natural folate). But are there times when a dietary supplement is needed? And are they safe to use in childhood? Before we answer that, let's first take a closer look at just what nutrients our growing children need and how much.
How are our little ones faring?
On the whole, our children are doing pretty well with food groups such as meat, fish, poultry, dairy and fibre. But some other areas provide quite startling statistics. Take vegetables for instance, if you include potato, fewer than 25% of four to eight-year-olds meet the recommended servings (this falls to less than 5% if you take potato out of the equation).
When it comes to fruit, the younger members of our society are doing pretty well, but fruit intake drops off dramatically with age. About 1-2% of teenagers consume very little fruit at all. Cereal is another area that could be greatly improved. Very few children reach the required level of three to four servings of cereals per day. In fact only about 20% of four to eight-year-olds are meeting those guidelines.
The A-Z of nutrients
Most of us are familiar in some way with the term RDI (recommended dietary intake) but you may have also seen a few more acronyms about. EAR and AI - neither of them are to do with body parts. The EAR (estimated average requirement) is the level of a nutrient required to meet the needs of 50% of a population, it is also the basis for setting an RDI. The AI (adequate intake) is used where we are not able to gain an RDI or EAR because there is not enough conclusive evidence. You may also see UL - this is the upper limit of a nutrient and has obvious relevance in relation to nutrients such as sodium, which does not have an RDI or EAR.
Getting enough calcium in childhood is essential because it helps set you up with the stores for the rest of your life. The RDI of calcium for toddlers is 500mg per day and by and large most two to four-year-olds are meeting that. It's recommended children consume at least two to three servings of milk or milk products such as yoghurt, custards or cheese each day. Other calcium-rich sources are almonds, figs, sunflower seeds, kelp (seaweed) and bony fish.
Children not only need adequate amounts of iron in their diet to grow but it's also vital for brain development in infancy. Interestingly, the RDI for infants shoots up from (AI) 0.2mg per day for newborns to 11mg per day for babies aged seven months to one year.
So, what would that look like on the plate? Well, one weetbix has 0.6mg of iron, a quarter cup of baked beans has 1mg iron, and half a cup of stewed lean beef mince offers 2.3mg of iron.
Encouragingly, a very high level of two to eight-year-olds are reaching their EAR for iron. While iron deficiency is one of the most common deficiencies, iron is also one of the most commonly over-supplemented nutrients. It's much better to try to meet a child's iron needs through food, and supplementation should only be under the advice of a qualified health professional.
There are many ways that iron-rich foods can be added into a child's diet (this may be of particular importance if meat foods are rejected or if the child is vegetarian). You can use iron-fortified cereals, flours and breads. Also, make sure you provide a food rich in vitamin C with each meal because vitamin C is important in helping absorption of iron. You can increase the number of ways meats are served (for example in quiches, stews, healthy pastries and scones) and increase the number of servings a week of iron-rich foods such as beef, lamb, chicken and fish. Also, use weaning formula and cereals fortified with iron.
There is now considerable evidence that women and children are at greater risk of iodine deficiency which can affect hearing and mental capability, and in severe cases, can result in goiter and hypothyroidism. New Zealand soils are low in iodine so many of our locally grown foods are also low in the nutrient. Where we once consumed plenty of iodine through iodised salt, a shift away from added salt as a result of its association with heart disease and blood pressure, means we need to source iodine elsewhere. As of October 2009 most breads in New Zealand and Australia have added iodine from the mandatory use of iodised salt in commercial breads.
Recommended daily levels of iodine are 110 micrograms (mcg) for seven to 12-month-olds, and 80mcg for toddlers. The New Zealand Ministry of Health also recommends all women who are pregnant, breastfeeding or considering pregnancy take an iodine supplement of 150mcg each day. However, iodine must not be taken in excess as it can have detrimental effects, which further supports the importance of diet first. Common dietary sources of iodine include oysters (probably not something on many toddlers' menus), sushi, canned salmon, bread made with iodised salt, snapper, cheddar cheese and eggs.
We need a certain level of sodium but this is one nutrient we tend to have more of than we should. Most of the sodium we consume comes from processed foods (up to 80%). Low-salt foods (foods with up to 120mg per 100 grams of food) are recommended for both children and adults and you should steer clear of foods that are high in sodium (over 1000mg per 100g) such as stock cubes, soy sauce, instant gravy, miso, instant soups, olives, ham, salami, tomato ketchup and feta.
Vitamin D is involved in the healthy functioning of a range of body systems including the brain and nervous system, pancreas, skin, muscles and cartilage, reproductive organs and some immune system cells. Our best source of vitamin D is sunlight and only 20% comes from our diet. Currently there's no RDI, only an UL (upper limit) of 80mcg per day for all children. Vitamin D is only found in significant quantities in a few foods, including egg yolks, liver, fatty fish and butter. For instance, canned red salmon on toast would provide only 6mcg.
But while sunlight is the best source of vitamin D, the downside of sun exposure is an increased risk of skin cancers. We don't know exactly how much sunlight children should be exposed to, but Maori, Pacific Island and others with darker skin may need up to six times that of Pakeha. That's why there's been recent discussion about fortifying our foods with vitamin D.
How do I know if my child is getting enough?
There are plenty of other vitamins and minerals essential to good health - zinc, magnesium, potassium, vitamins A, B, C, E and K to name just a few. My advice is to not get too caught up in the intricacies. Your best course of action is to offer your child a well-balanced diet. But if you're worried that she may be deficient in some way, then there are things you can do. My first suggestion is to record everything your child eats and drinks on a given day. One day is the easiest to measure, but the more days you chart the more accurate the result. Now simply add up the number of serves your child has had from each of the food groups using a food group chart. You'll find plenty of examples of food charts online but there is also one available from here. Once you've identified a problem area, you can take action by including more of the foods suggested on the charts.
Generally, when food is presented on a plate, each of the food groups should be represented in roughly the following proportions - half carbohydrates, one third protein and unlimited vegetables. If you are still concerned, record a minimum three-day diet diary and discuss it with your GP or a nutritionist.
Can't I just take a supplement?
There is ongoing concern about the widespread use of supplements. One concern government agencies have is whether we as consumers understand the potential for toxicity. There is concern that the view "more is better" prevails and that supplements are used to compensate for poor eating habits.
Increasingly, research points to the deleterious effects of high doses of certain nutrients. For example, large doses of zinc can affect the uptake of iron and copper; excessive fluoride can have negative effects on bone; high doses of fish oils can impair blood clotting and too much calcium can inhibit iron uptake (common in children who drink large amounts of cows' milk for example). If you are considering a supplement then I encourage you to seek the advice of your GP or a nutritionist.
Don't feel bad if your child doesn't have the perfect diet
If your child simply refuses to eat fruit, vegies or meat, trust me, you are not alone! As parents we don't need to feel any more guilt but yes, we may need to tidy up the edges a little. Simply, we need to keep the home for healthy stuff and leave all the lollies, juices, cakes and pies for special occasions. Focus on what is eaten as opposed to what isn't to ensure meals are positive events. Until your child hits her teen years you still have reasonable control over what she eats.
If you have let things slip, as we all do at some time or another, and are reflecting on the state of your cupboards, newly filled with chips and biscuits or the freezer with ice cream, then slowly cut back. Leave fruit and healthy options in easy-to-access places and encourage children to snack on fruit, healthy crackers, yoghurt and so on.
Childhood nutritionist Leanne Cooper is mum to two quick-minded, fast-talking, sometimes Luke Skywalker, other times Ben 10 mimics, Zach and Samuel. Heading up Cadence Health, a nutrition education business, and Sneakys Kids Nutrition, Leanne is author of What Do I Feed My Baby? and other childhood nutrition titles. Kiwi ex-pat Leanne, husband Don and their two boys live on the Northern Beaches of Sydney.