Frequently Asked Questions

Why have I been invited to participate?

You have been invited to participate in this study because you are the parent or caregiver of a child who has not begun eating solids.

You also plan to introduce your child’s first foods around 6 months of age (as per the Ministry of Health Food and Nutrition Guidelines).

What is the first food you’re using?

The whole food that we are interested in using is kūmara which will be provided to two thirds of participants in the form of a powder. The kūmara powder is to be mixed with water to form a paste. This is then added to any foods that you give your baby throughout the study. We hope that your baby will be able to consume 5 g (1 tsp) of kūmara powder every day. Kūmara is a widely accepted food to be offered to infants as a first food. There are no perceivable risks associated with your baby consuming kūmara.

What is the difference between the kūmara powders?

There are two different kūmara products being used. One is standard kūmara that has been cooked and freeze-dried. The other is freeze-dried kūmara that has a small amount of added resistant starch from green bananas.

Safety Message

Both treatment groups involve the use of accepted ingredients in infant nutrition and are manufactured in registered facilities that comply with Food Standards Australia and New Zealand guidelines with respect to manufacturing standards and compliance with food safety requirements, including allergy management. There are no known ingredients which might conceivably cause harm.

Where has the study received ethical approval?

This study has received ethical approval from:
The Northern A Health and Disability Ethics Committee (Reference: 20/NTA/9).

What does being a part of this study include?

By being a part of this study you are agreeing to give your baby the required amount of kūmara powder for a total of 4 months.

Over the duration of the study you will be asked to participate in measurements at three time points

  • Time point 1: when your baby is around 4½ – 6 months of age (before you introduce any first foods)
  • Time point 2: when your baby is around 8 months of age
  • Time point 3: when your baby is around 10 months of age

Will I get any benefit from participating in this study?

Taking part in this study will help us understand how the introduction of complementary solid foods and changes in milk consumption impacts infant gut bacteria, sleep behaviour and immune function. You may also learn useful information on the role of gut bacteria in immune health during early life. Your involvement in this study is of great value to the researchers; thank you for considering taking part.

What if I am randomised to be in the control group?

If you are in the control group you don’t need to remember to feed your child daily amounts of kūmara powder. Everything else in the study is the same. You will get results of your child’s eating patterns and the effect of this on their microbiome, as well as analysis of their sleep behaviour and immune function. Each clinic visit you will be given a supermarket voucher to the same value of two months of the kūmara powder.

Will taking part cost me anything or will I be paid?

Taking part in this study should not cost you anything apart from your time, for which we thank you. When visiting the School of Medical and Health Sciences, Grafton Campus for measurement sessions in clinic, reserved parking will be arranged for you by the study team. Please let the study team know if there is a problem getting to your clinic appointment, as transport arrangements can be made or transport vouchers provided. The kūmara powder will be supplied to you at no cost for the duration of the study, or you will receive a supermarket voucher for the same value, and all participants will receive a koha (gift) in the form of vouchers as an expression of thanks for dedicating time to this research.

How will my confidentiality be protected?

We treat protection of your personal information as a matter of high priority. Your confidentiality and privacy are guaranteed during your participation in this study. The researchers will de-identify all personal information provided by you and there is no risk that you will be able to be identified should the results of this study be published. Any identifiable information collected about you, your whānau/family or your baby during this study will remain confidential and will only be revealed with your permission, or except as required by law.

On entering the study, you will be given a unique study identification number, which will be used for identification on all forms, questionnaires and measurements. Any documents, including paper copies of questionnaires, data collection forms or measurements will be stored in locked filing cabinet in a secure swipe-access area at the University of Auckland, where only the research team has access. The SUN study researchers will be trained and monitored by an independent committee, who will ensure the study is carried out according to the guidelines for Good Clinical Practice. An additional independent Data Management Committee will be responsible for the interests and safety of the study participants (mothers and their baby’s).

What will happen with my blood, stool and breast milk samples?

Blood: Analysis of blood samples will take place at AgResearch (Palmerston North) and Malaghan Institute (Wellington). Blood samples will be collected by an experienced person and analysed to assess your baby’s response to the rotavirus and pneumococcal immunisations and understand the different metabolites present in response to the kūmara powder intervention. Metabolites are a unique ‘fingerprint’ that describes cell function.

Stool: Your baby’s stool samples will be analysed to assess how the kūmara powder intervention has affected their gut microbiota (the types of gut bacteria present) and also assess your baby’s immunisation response (to the immunisations mentioned above). Stool samples from mothers will be used to compare any similarities or differences between mother and baby gut bacteria. Samples will be analysed at AgResearch (Palmerston North) and a small amount of your baby’s stool sample prepared in a solution (approx. 0.05 mL per tube) will be sent overseas, frozen on dry ice, to Teagasc, Agriculture and Food Development Authority in Ireland (Oak Park, Carlow R93 XE12, Ireland) for expert analysis of your baby’s gut bacteria variety. All samples will be transported according to international guidelines for the transport of human tissue.

Breastmilk: If you are breastfeeding and can provide three breastmilk samples throughout the study, this will be analysed for the role of immunisations and immune factors in shaping your baby’s gut bacteria and the change in breast milk composition (of fats, carbohydrates, proteins and bacteria) that occurs when breastfeeding throughout the complementary feeding phase. Breastmilk samples will be analysed at AgResearch (Palmerston North) and Malaghan Institute (Wellington).

What if I no longer wish to participate in this study?

Taking part in this study is your choice and is completely voluntary. You are free to withdraw your child at any time without having to explain why. Withdrawing from the study will not influence any future involvement you might have with the University of Auckland. Should you withdraw from the study, any information that has been previously collected will be retained to ensure that the results of the research project can be measured properly, unless you specifically ask for these to be removed.

What happens with the results?

If you give us your permission by signing the Consent Form, findings from the study will be used in internal reports, conference presentations, and research publications. Participating whānau/family will be provided with a report detailing the main study findings and any implications this may have for you.

The results will be stored using a coded number on a computer at the University of Auckland. Any data collected in paper form will be stored in a locked room. After completion of the study, we will keep your data for 10 years after the youngest participant has turned 16 years-of-age. You will only be contacted in the unlikely event that we would like to perform further unspecified analysis. If we cannot contact you at this time, we will not perform this analysis on your samples.

What should I do if I want to discuss the study further before I decide?

When you have read this information a member of the study team will discuss it with you and answer any questions that you may have. You may wish to talk about this study with other people such as family/whānau, friends, or healthcare providers. If you would like to know more at any stage, please do not hesitate to contact the trial coordinator (Robyn Lawrence) directly at