Diet and Nutrition Survey of Infants and Young Children in Scotland, 2011

Chapter 1 Background and purpose

1.1. Introduction

The Scottish Government and the Food Standards Agency in Scotland (FSAS) funded a boost to the Department of Health (DH) and Food Standards Agency (FSA) commissioned Diet and Nutrition Survey of Infants and Young Children (DNSIYC). This report provides detailed information on food consumption and nutrient intakes of infants and young children in Scotland, which will be used to provide a robust evidence base for work in Scotland to develop and implement sound public health policies.

Breast milk is the ideal form of nutrition for infants and exclusive breastfeeding^[1] is recommended for the first six months (26 weeks) of an infant's life^[2],[3]. The Scottish Government has adopted as policy the World Health Organisation guidance recommending exclusive breastfeeding for the first six months of an infant's life, and recommends around six months as the age for introduction of complementary foods^[4],[5]. Breastfeeding (and/or breast milk substitutes, if used) should continue beyond the first six months, and for as long as the mother wishes. Complementary feeding should be adequate, meaning that the complementary foods should be given in quantities and at a frequency and consistency that will meet the nutritional needs of the growing child while maintaining breastfeeding and/or feeding breast milk substitutes. A variety of foods should be used. The current feeding policy for infants and young children is designed to optimise nutrition at a specific stage of growth and development. Therefore, food and nutrient intakes should not be compared to nutrient guidelines set for older children or adults.

In January 2011, the Scottish Government published a framework to improve the nutritional health of both mothers and infants in Scotland entitled "Improving Maternal and Infant Nutrition: A Framework for Action"^[3]. It is the first framework which looks at the nutrition of mothers before and during pregnancy, supports and promotes the benefits of breastfeeding and the importance of a healthy diet throughout early childhood. The framework was developed on the principles outlined in Better Health, Better Care^[6], Getting it Right for Every Child^[7] and the NHS Healthcare Quality Strategy^[8]. It stresses the importance of nutrition in the earliest years for long term health and wellbeing, and provides case studies demonstrating good practice already in place across Scotland. The framework action plan contains a number of actions to be taken forward by NHS Boards and other responsible organisations, designed to promote optimal nutrition for pregnant women, infants and young children and support parents to provide a healthy diet for their families.

In Scotland, the Scottish Government will obtain comprehensive information on the dietary habits and nutritional status of the Scottish population through a boost of the National Diet and Nutrition Survey (NDNS)^[9] rolling programme, which is conducted on a sample of the UK population, including Scotland, aged 1½ years and over. Results for Scotland will be published early in 2014. However, the current NDNS rolling programme, and earlier surveys including the survey of children aged 1½ to 4½ years (1995)^[10], do not collect information on those under 18 months of age. The last national survey of infants, an investigation of food and nutrient intakes of British infants aged 6 to 12 months^[11], was commissioned by the Ministry of Agriculture, Fisheries and Food (MAFF) and carried out in 1986/87. Since 1975, information about feeding practices of infants and young children up to the age of 10 months has been derived from the Infant Feeding Survey (IFS)^[12], which is currently carried out every five years, with support from the Scottish Government and the General Registrar of Scotland as well as the equivalent organisations from the other countries of the UK. However, the IFS does not collect information on actual quantities of foods consumed. Government advice on breastfeeding, complementary feeding and dietary habits has changed since the last dietary survey of this age group was carried out in the 1980s indicating a call for more current information. There was therefore a need to address the gap in the evidence base for this age group.

Following a tendering process, DH and the FSA commissioned a consortium comprising MRC Human Nutrition Research (HNR) based in Cambridge, NatCen Social Research^[13] (NatCen) based in London, the MRC Epidemiology Unit based in Cambridge and the Human Nutrition Research Centre at Newcastle University to carry out DNSIYC, a survey of infants and young children aged 4 months up to 18 months in the UK^[14]. The fieldwork in Northern Ireland (NI) was carried out by the Northern Ireland Statistics and Research Agency (NISRA).

DNSIYC provides detailed information on the diet and nutrition of individuals aged 4 up to 18 months^[15], from private households. The data from DNSIYC will be used alongside data from NDNS to provide a fuller picture of the diet and health of the nation, than is possible from data previously available, starting from the age at which complementary feeding typically begins. This will support public health policy and food safety assessments. The survey was carried out in all four countries of the United Kingdom (UK) and was designed to be representative of the UK population. Additional recruitment was undertaken in Scotland and among those in receipt of Healthy Start (HS) vouchers^[16], in order to provide more detailed analysis of these populations. This report summarises the results of the Diet and Nutrition Survey of Infants and Young Children in Scotland (DNSIYCS), which was commissioned as part of DNSIYC in the UK. The results for HS sample in Scotland are presented in Chapter 6 of this report. The UK DNSIYC survey forms a separate report published on the DH website and details of the boosted UK Healthy Start sample are presented in Annexe A of the UK report.

DNSIYCS provides important background data about the dietary intakes of children from 4 up to 18 months to inform the programmes resulting from the launch of the maternal and infant nutrition framework.

The UK survey involved two stages; Stage 1 consisted of a series of home visits to collect background information and carry out the dietary assessment components of the survey, as well as physical measurements of the child (length, weight and head circumference) and mother (height and weight); Stage 2 was a clinic visit consisting of additional physical measurements of the child (skinfold thickness measurements), measurement of body composition of the child, and estimation of breast milk and fluid intake using stable isotopes. A blood sample was also taken from the child for assessment of iron and vitamin D status.

This report presents findings from the survey for Scotland. The Scottish survey was a dietary survey only and did not report results for the clinic stage of the survey as Scottish boost participants were not invited to attend a clinic. Fieldwork was carried out between 6 January 2011 and 23 May 2011. Pilot work to test methods of the survey is reported in Annexes B and C of the UK report.

The aims of DNSIYCS were therefore to:

• Provide detailed, quantitative information on the food and nutrient intakes and sources of nutrients of a representative sample of infants and young children aged 4 to 18 months from the Scottish population, as a basis for developing government policy and measuring progress towards government objectives.
• Provide detailed, quantitative information on breast milk and breast milk substitutes consumed by the population group under study.
• Describe the characteristics of participants with intakes of specific nutrients that are above and below national reference values, and evaluate the diet of this population compared to current national recommendations.
• Contribute to a database of food consumption to provide the basis for the calculation of likely dietary intakes of natural toxicants, contaminants, additives and other food chemicals for risk assessment.
• Provide height (length), weight and head circumference and examine their relationship with dietary intake and health and social factors.
• Examine the extent to which feeding practices adopted by carers of this population group differ from national policy for infant health.
• Provide some information on the dietary habits of the mother (and other key family members) and link this to the nutrient intakes of this population group.

National recommendations for nutrient intakes are listed in relevant chapters.

1.2. Structure of this report

The following chapters detail the methods and results for the Scotland sample, including the boosts.

• Chapter 1: Background and purpose of DNSIYC and DNSIYCS
• Chapter 2: Preliminary studies, research designs and methodology
• Chapter 3: Sample characteristics and survey response rates
• Chapter 4: Physical measurements
• Chapter 5: Feeding practices
• Chapter 6: Food consumption and nutrient intakes