Dietary Management

It is important that food management starts early. It is far easier to start outright than to remove privileges because of weight gain. It is also important that you recognise that food-seeking will be a problem which may result in morbid obesity, and that you take steps to control this before it becomes a life-threatening situation.

Download the pdf  "Need to Know Nutrition" 

Need to Know Nutrition_Peter Davies.jpg


To understand the importance of this hunger drive, try to look at PWS as a 'starvation' syndrome rather than an over-eating one. Because of the dysfunction in the hypothalamus, there is no on/off mechanism that tells the brain, "I've eaten enough". What happens instead is that the brain keeps telling the stomach, "you're starving, you need food", and the drive to find food overrides everything else.



Without support and good management, what started out in the baby as failure to thrive, will lead to morbid obesity.  The vast majority of people with PWS show excessive eating behaviours including stealing food, stealing money in order to buy food, taking food from others, breaking locks on cupboards, and so on. They often display an extraordinary ability to find food and just when you thought it was safe to leave the room for a few moments, you'll return to find something missing! Added to this is an inability to reason bewteen right and wrong when it comes to food-seeking, and you have the makings of some serious behavioural challenges.



Unfortunately it is also very easy for people with PWS to gain weight, due to the combination of the overriding desire to eat, coupled with the low muscle tone (if growth hormone has not been used) which makes exercising difficult, slow, and therefore no fun. Therefore managing weight gain in PWS becomes even more critical.



Management also means locks on pantries, fridges, food cupboards - not straight away, but when food-seeking becomes apparent. Although this might seem antiquated and unfair, it is incredibly helpful to the person with PWS to know that food is secure and is not a temptation to them.



Calories are what the body uses as its source of fuel and energy. Energy from food is calculated in calories to give a quantity we can measure. For example, a boiled egg has 80 calories. Although the correct terminology for calories is Kilocalories (kcals) and, even more confusingly, kiloJoules (kJs), which are becoming increasingly more used as food measurement, we will stick with the measurement of calories.



All foodstuffs are now required by law to carry a label stating, among other things, the energy level (or calories) per 100g. You will find that this will often be stated as kiloJules or kJs. A rough guide to convert to calories is to multiply by 4.  How many calories does a person with PWS need? This will vary, of course, depending on the age and physicality of the person. For an overweight adult (not on growth hormone therapy), a diet of 1,000 calories per day is recommended. That breaks down into around 300 calories per meal (3 a day) and 100 calories left over for snacks. It's not very much, but because of the comparative inability for a person with PWS to exercise off 1,000 calories a day, it becomes very necessary to restrict food intake.



Exercise - even of the slowest kind - needs a certain amount of energy, and therefore burns calories. It is an extremely important part of managing weight. The only way to lose weight is to burn off more calories than we eat. For example:



  • Sitting for one hour and not doing much, will use 100 calories

  • Doing housework for one hour, will use 180 calories

  • Gardening for one hour, will use 220 calories

  • Brisk walking for one hour, will use 330 calories, and

  • Jogging for one hour, will use up 750 calories.



Try to encourage exercise at all times - even hidden exercise, such as hanging out the clothes, window-shopping, parking further away in the supermarket car-park, climbing the stairs, helping push the supermarket trolley etc, is better than none. There are all sorts of exercises designed to strengthen muscles and if your child is under a physiotherapist, make sure you start an early exercise programme and... make it fun!



Growth hormone treatment will help strengthen muscles, improve energy levels and enable a much greater level of physical participation. It does not mean that the appetite will decrease, or food-seeking will disappear, but it will help enormously with the development of good muscle tone which will improve your child's ability to exercise.

Without growth hormone treatment, a regular exercise programme is essential and management of diet is critical. It is much harder for a person to exercise if they are over-weight, so try to involve them in your planning so that they can choose things to do that they enjoy.


Download the pdf  "Need to Know Nutrition" 

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