Kids: obesity, hyperactivity, allergies


In this article, DietDoc takes a look at obesity, hyperactivity and food allergies, which are all diet-related problems that can affect schoolchildren between the ages of seven and 10 years.

Childhood obesity
There is growing concern about the high incidence of childhood obesity. Surveys indicate that up to 12% of children between the ages of seven and 10 years are obese. Fat children are exposed to many stresses, including discrimination, poor self-image, and lack of social skills. It is imperative that parents should recognise that their children are obese and do something about the problem.

What should young schoolchildren weigh?
The following average weight and height figures can be used as a guideline when assessing the growth of schoolchildren:

Weight in kg22242628
Height in cm117123128132

Remember that these are average figures and that growth does not occur exponentially, but in fits and starts. Periods of relatively rapid growth and weight gain will be followed by periods of latency, when the height and weight of the child remains practically constant.

Overweight in young schoolchildren is associated with a number of misconceptions, such as:

  • "Puppy fat - he will grow out of it again!" This is usually not true and obese children often develop into obese teenagers and obese adults. The longer a child has been overweight, the more likely it is that he will stay fat for the rest of this life. And this is not a legacy you want to give your child.
  • "Children need to eat as much as possible to grow." This is also not true and if you reinforce “cleaning your plate” habits, your child may associate overeating with approval. Avoid forcing children to eat, unless they are developing childhood anorexia (this is generally a very rare condition).

Contributing factors

  • Excessive intake of food. Some parents equate food with love and force their children to eat inappropriately large quantities of food. If you are guilty of this negative behaviour, stop immediately and seek the help of a clinical dietician who will work out a diet for your overweight youngster and teach you, as the parent, what portion sizes are appropriate for your child.
  • Excessive intake of sweetened beverages (cold drinks and fruit juices). Recent research conducted in the USA indicates that energy consumed in the form of liquids (cold drinks and fruit juice), may make a larger contribution to childhood obesity than solid foods. It is suggested that the human body is less capable of compensating for excess energy ingested in liquid form. So, if your child drinks litres of cold drinks and fruit juice, start re-educating her immediately. Tell her why she needs to cut down on cold drink and fruit juice, and offer her low-energy alternatives such as bottled, flavoured water, tap water, rooibos tea and fat-free milk.
  • Lack of physical exercise. This is probably the major reason for the boom in childhood obesity. Children used to use up large amounts of energy by playing and participating in sport. Nowadays, young children spend hours and hours a day sitting in front of the TV or computers, turning them into ‘couch potatoes’. If your child is overweight and inactive, you need to make sure that he limits the amount of time spent in front of the TV and/or computer, and that he starts to participate in sport. If his school does not offer sporting activities for ordinary children and only promotes ‘top athletes’, find a club or gym that your child can join, teach him to swim and cycle, and if necessary join him in doing exercise.

Every action you take to prevent your child from gaining weight and/or encouraging her to lose weight and become more active, will pay off in your child’s later life.

Hyperactivity or Attention-Deficit Hyperactivity Disorder (ADHD) or Attention-Deficit Disorder (ADD), often manifests itself in the early school years. ADHD is associated with symptoms such as excessive physical activity, impulsiveness, poor concentration, and low frustration tolerance.

Despite extensive research to investigate dietary links to ADHD (e.g. sugar, MSG, colorants), controlled challenge studies (i.e. hyperactive children were given doses of sugar to ‘challenge’ their reaction) were unable to demonstrate a connection between sugar intake and hyperactivity. In fact, children receiving sugar in one of these studies were actually calmer and quieter than those who did not receive sugar.

The latter finding may be due to the fact that hyperactive children have a great need for energy replacement. In contrast to most children, who are in danger of becoming ‘obese couch potatoes’, children with ADHD are so active that they need to eat large quantities of food and often. If your child is hyperactive it is important to consult a clinical dietician and to make sure that he is getting sufficient nutritious food to meet his needs for energy.

The late afternoon period, when the child becomes fractious due to low blood sugar levels, is usually particularly difficult. Offer him a nutritious snack such as low-fat milk with wholewheat bread and peanut butter or dried fruit and cheese with wholewheat crackers. You may find that his mood improves dramatically, while the stress levels in the family decrease.

For hyperactive children the rule of ‘not eating between meals’ does not apply. These children need to eat when they are hungry or when their blood sugar levels dip, but make sure that the foods they eat are rich in healthy nutrients (low-fat milk or yoghurt, wholewheat bread and crackers, peanut butter, dried or fresh fruit, cheese, nuts or even an energy drink such as Game or Lucozade).

It is also emerging from research that hyperactive children have a pronounced need for omega-3 fatty acids. Try giving your ADHD child an omega-3 supplement such as salmon oil capsules or omega-3 enriched food (eggs, milk and bread, which should be available in your supermarket).

Certain allergies of infancy may clear up during the childhood years, while others may appear for the first time.

If you suspect that your child is sensitive to certain foods or food additives, ask your GP to send her for allergy tests. Self-diagnosis is self-defeating and can have serious consequences, such as nutritional deficiencies.

For example, if you think your child is allergic to milk and you cut out all milk and dairy products without having this diagnosis confirmed with tests, your child runs the risk of developing a calcium deficiency. She could just as well be allergic to pollens and grass, not food, and you may be depriving her of nutritious foods to no advantage.

Remember that the incidence of true food allergy in children is low (between one and three percent). If your child tests positive for a food allergy, you must consult a clinical dietician to help you work out a diet that avoids the offending food(s), but is still sufficiently nutritious to promote the vital growth and development that takes place during the childhood years.

Don’t try to do it on your own. The support of a nutritional expert is essential and will pay off by ensuring that your child does not develop the negative symptoms of the food allergy, and that normal, healthy growth is guaranteed.

(Dr I.V. van Heerden, DietDoc)

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