Diet and Nutrition

Newborns with Prader-Willi Syndrome do not feel hungry, and due to low muscle tone, it is very hard work for a baby with Prader-Willi Syndrome to latch onto the breast and suck. The nasal-gastric tube is something most babies with PWS will use for a period of time. It is a small tube that is passed into the nose, down the throat and into the baby’s stomach.

A speech therapist and dietician can assist during the ‘tube weaning’ process to ensure that the infant is receiving adequate nutrition once the tube is removed. Most commonly a combination of feeding methods (nasal-gastric tube and breast/bottle) is used during infancy. 


There have been very few cases in the PWS community where breastfeeding has been achieved, but if this is your goal we recommend you seek the advice and support from a lactation consultant who will work closely with you to try to achieve this. Please remember that whichever feeding method you choose (breast or bottle), expressing and using breastmilk is certainly encouraged if possible but it is a personal decision and there are many fantastic formulas available. 

Bottle Feeding

There are numerous types of bottles and teats available and it really is trial and error. The Habermann bottle is popular as the teat can be squeezed to help fluid trickle into your baby’s mouth and assist with feeding. Hospital staff or a specialist speech therapist can assist with advice about trialing different teats and bottles.

Optimal Nutrition

The diet of someone with Prader-Willi Syndrome can be very different from the general population who are trying to maintain their weight. 

As we are learning more every day about Prader-Willi Syndrome, it is essential that your dietician understands; or is willing to learn about Prader-Willi Syndrome, and is abreast of all the latest research in their respective field of expertise. Foods that were once thought to be beneficial in a PWS diet may not be today.

In infancy, it is important to keep a schedule for feeding, as your baby may not wake or cry to be fed. In these early stages of life, adequate nutrition including fat is imperative for your baby to thrive and for brain development. Your baby’s feeds must never be restricted and in fact many are supplemented with additional kilojoules.  It is important to seek the advice of a dietician during this time and the hospital should be able to assist with this.

Even out of hospital, Nutrition Therapy or consultation with a dietitian can assist you in developing and adjusting a feeding plan for your child. A dietitian experienced in Prader-Willi Syndrome can help you ensure your child is receiving the vitamins and nutrients needed for optimal development, while also considering your child’s specific energy (kJ) needs. Assistance from a dietician will continue well beyond infancy.

As your child begins exploring solid foods, it is essential to begin a healthy eating routine. A good menu will include vegetables, proteins, fruits, dairy and good fats, preferably as whole foods. Research has been conducted on a range of different diets and their effect on people with Prader-Willi Syndrome. As with the general population, the truth is that some foods will work for some and not for others. The key to a healthy diet is creating something sustainable, and that works for you.

It is important to keep your child well hydrated. The preferable drinks being water and milk. Fruit juice, although natural, has as much sugar as a soft drink in the form of fructose, and this is rapidly released into the body unlike a piece of whole fruit. While you would not typically give your child several apples as a snack, the equivalent amount can be swallowed easily in a glass of fruit juice and is less satisfying. The same can be said for dried fruits, with decreased volume and concentrated fruit sugars. Be guided by your dietician before replacing full fat milks, yogurts etc. with low-fat varieties as fat is essential for healthy brain development. 

Even before the onset of hyperphagia, the rule of thumb is to make each bite nutrient-dense. Now or in the future, your child will need to have restricted kilojoule meals. The kilojoules in some foods are higher than others with highly refined food, sometimes containing a full day’s nutritional requirement.   

Nutrient dense foods are foods that are  :

  1. Good for the overall health; and  
  2. Can be consumed in greater amounts and are more satisfying to the body and the mind of the person with Prader-Willi Syndrome.

You are probably aware that these guidelines should apply to us all. Having a family that shares the same eating habits will not only support your own good health but will make it easier when preparing meals and will set an excellent example to support your young child on their journey. Teaching your child that every person has different requirements for their unique body can help with the inevitable comparing of meal sizes.  

Food Seeking and the early stages of Hyperphagia

Of all the topics regarding Prader-Willi Syndrome, Hyperphagiawhich is the insatiable drive to eat and of never feeling full, is the most well-known, most misunderstood and not necessarily the most significant issue when living with PWS.  Like most aspects of Prader-Willi Syndrome, hyperphagia occurs at a widely varying age of onset and intensity.                          

Hyperphagia does not occur in infants and it is important to not restrict an infant’s diet. 

Somewhere between the ages of three and eight, children with Prader-Willi Syndrome may begin to experience a preoccupation with food. At first, you may start to notice an increase in weight without increased appetite or excess calories; this can later be followed by an increased appetite and interest in food with the ability to feel full. It is hard to recognise the difference between normal toddler behaviour and the beginning of this Hyperphagia stage. During these early years, it’s essential to work with a dietician who understands Prader-Willi Syndrome who can provide advice and guidance to ensure optimum nutritional needs are being met. An Occupational therapist can also assist with adequate environmental controls.

Like all toddlers, your child may be a picky eater with strong likes and dislikes for particular foods. However, this is a significant time of education for your child, yourself and your family, friends and carers.  It is imperative, to begin with, a healthy eating routine and safe environment as you will need to continue this into adulthood. It is much easier not to introduce a particular food than to remove it from the menu at a later date. 

Early implementation of no snacking outside of set meal and snack times is essential, and treats of highly processed foods should not be offered. Rules, such as not helping yourself to food and no second helpings at mealtimes are all good practice. Modelling healthy food choices and eating habits makes it easier for your child also to understand and make good choices and gives a clear message or guideline to extended family. 

Because the body composition in individuals born with Prader-Willi Syndrome is imbalanced, with a higher ratio of fat to lean muscle, it is surprisingly easy for individuals to gain weight in a very short period of time. Lower amounts of lean muscle result in less energy being used and low tone can make exercise difficult. 

A person with Prader-Willi Syndrome will need to have a well-balanced, low-calorie diet and maintain regular exercise for the rest of their life. Height, weight, and BMI should be monitored every 6 months during the first 10 years of life after infancy and Is regularly monitored throughout their life to make sure a healthy weight is maintained.

Further Information

Further information with regards to Optimal Nutrition for People with PWS can be found on the Foundation for Prader-Willi Research website.

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