Secular trends in infant feeding practices during the first year of life in Norway: findings from 1998 to 2019 - the Spedkost surveys

The aims of the present study were to assess secular trends in breast-feeding and to explore associations between age at introduction of solid foods and breast-feeding duration. Data from three national dietary surveys in Norway were used, including infants born in 1998 (Spedkost 1, n 1537), 2006 (Spedkost 2, n 1490) and 2018 (Spedkost 3, n 1831). In all surveys, around 80 % of the infants were breastfed at 6 months of age. At 12 months of age, breast-feeding rate was 41 % in Spedkost 1, increasing to 48 % in Spedkost 2 and 51 % in Spedkost 3. Compared with earlier introduction, introduction of solid foods at ≥ 5 months of age was associated with a lower risk of breast-feeding cessation during the first year of life in the two most recent Spedkost surveys. In Spedkost 2, the adjusted hazard ratio for breast-feeding cessation during the first year of life for those introduced to solid foods at ≥ 5 months of age was 0·43 (95 % CI (0·31, 0·60)), P < 0·001, while the corresponding number in Spedkost 3 was 0·44 (95 % CI (0·29, 0·67)), P < 0·001. In conclusion, breast-feeding at infant age 12 months increased over time. Introduction of solid foods at ≥ 5 months of age was positively associated with breast-feeding duration in the two most recent Spedkost surveys. As breast-feeding contributes to numerous health benefits for infant and mother, and possibly improved dietary sustainability in infancy, findings point to the importance of continued protection, support and promotion of breast-feeding.

Exploring intervention components in association with changes in preschool children's vegetable intake: the BRA-study

Objective

The present study aimed to explore kindergarten staffs’ perceived usefulness of intervention components in association with changes in children’s vegetable intake and vegetables served in the kindergarten. Assessment of the perceived usefulness of intervention components consisted of a paper-based questionnaire for the kindergarten staff assessing usefulness of posters, supplementary material and 1-day inspirational course. Children’s vegetable intake in the kindergarten was assessed by direct observation, while vegetables served was assessed by a 5-day weighted vegetable diary.

Results

Seventy-three kindergartens in two counties in Norway participated (response rate 15%) and parental consent was obtained for 633 children 3–5 years of age at baseline (response rate 39%). Mixed effect models indicated a tendency that posters were associated with increased child vegetable intake (P = 0.062). Surprisingly, a low degree of perceived usefulness of supplementary material was associated with the largest increase in child vegetable intake (P = 0.020). No significant associations between perceived usefulness of intervention components and vegetables served in the kindergarten were found. This study indicated a tendency that posters were associated with increased child vegetable intake; however, this may also be due to synergies between multiple intervention components.

Trial registration International Standard Randomized Controlled Trials ISRCTN51962956 (http://www.isrctn.com/ISRCTN51962956). Registered 21 June 2016 (retrospectively registered).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-021-05629-1.

Long-term effects of a cluster randomized controlled kindergarten-based intervention trial on vegetable intake among Norwegian 3-5-year-olds: the BRA-study

Objective

To report on long-term effects of a cluster randomized controlled kindergarten-based intervention trial, which aimed to increase vegetable intake among Norwegian preschool children (3–5 years at baseline). The effects of the intervention at follow-up 1 (immediately post-intervention) have previously been published. This paper presents the effects of the intervention from baseline to follow-up 2 (12 months post-intervention).

Results

Parental consents were obtained for 633 out of 1631 eligible children (response rate 38.8%). The effects of the intervention from baseline to follow-up 2 were assessed by mixed-model analyses taking the clustering effect of kindergartens into account. Children’s vegetable intake was reported by the parents at baseline (spring 2015), at follow-up 1 (spring 2016) and at follow-up 2 (spring 2017). No significant long-term effects in child vegetable intake were found. A mean difference of − 0.1 times per day (95% CI − 0.5, 0.2) (P = 0.44) was found for the daily frequency of vegetable intake. A mean difference of – 0.2 different kinds of vegetables eaten over a month (95% CI − 1.0, 0.7) (P = 0.70) was found and for daily amount of vegetables a mean difference of − 15.0 g vegetables (95% CI − 38.0, 8.0) (P = 0.19) was found.

Trial registration International Standard Randomised Controlled Trials ISRCTN51962956 (http://www.isrctn.com/ISRCTN51962956). Registered 21 June 2016 (retrospectively registered)

Infant cholesterol and glycated haemoglobin concentrations vary widely-Associations with breastfeeding, infant diet and maternal biomarkers

AIM

Elevated total cholesterol (TC) and glycated haemoglobin (HbA1c) are risk factors for cardiovascular disease; however, little is known about their determinants in infants. We aimed to describe TC and HbA1c concentrations in infants aged 8-14 months and explore the relation between infant TC, HbA1c, breastfeeding, infant diet, and maternal TC and HbA1c.

METHODS

In this cross-sectional pilot study, mothers of infants aged 6 and 12 months were invited to complete a food frequency questionnaire and to take home-based dried blood spot samples from themselves and their infants.

RESULTS

Among the 143 included infants, the mean (SD, range) concentration was 4.1 (0.8, 2.3-6.6) mmol/L for TC and 4.9 (0.4, 3.7-6.0)% for HbA1c. There was no significant difference between age groups and sexes. There was a positive relation between TC concentrations of all infants and mothers (B = 0.30 unadjusted, B = 0.32 adjusted, P < .001 for both) and a negative relation between infant TC and intake of unsaturated fatty acids in the oldest age group (B = -0.09, P = .03 unadjusted, B = -0.08, P = .06 adjusted). Infant HbA1c was not significantly related to diet or maternal HbA1c.

CONCLUSION

TC and HbA1c concentrations varied widely among infants aged 8-14 months. Infant TC was associated with macronutrient intake and maternal TC.

Exploring the workplace climate and culture in relation to food environment-related factors in Norwegian kindergartens: The BRA-study

BACKGROUND

Kindergartens represent an important arena for promoting vegetable intake when it is essential to establish healthy dietary behaviours early in life. To develop and implement successful interventions targeting dietary behaviours in kindergartens, a good understanding of the factors influencing their food environment and the interplay between these factors is essential. The present study aimed to explore associations between workplace climate and culture in the kindergarten setting and the staff's food-related practices, vegetables served and the possible mediating role of staff's food-related practices.

METHOD

Vegetables served, staff's food-related practices, and data on workplace climate and culture were collected using a 5-day, weighted, vegetable diary and three paper-based questionnaires. Seventy-three kindergartens in the Norwegian counties of Vestfold and Buskerud participated in the study. Spearman's rho was used to assess the association between workplace climate and culture, and staff's food-related practices and vegetables served. Mediation analyses were conducted to assess the mediating role of staff's food-related practices in the relationship between workplace climate and culture and vegetables served in this setting.

RESULTS

There was one significant positive correlation between factors in the workplace climate and culture, and staff's food-related practices and vegetables served. The staff's food-related practices were found to mediate the association between support from superior and the variety of vegetables served. They also mediated the association between commitment to the organization and the frequency, as well as the variety, of vegetables served.

CONCLUSION

The results identified commitment to the organization and support from superior as two important factors in the workplace climate and culture. Furthermore, these two factors seems to be important to target when developing kindergarten-based interventions aimed at increasing the variety and frequency of vegetables served as they were associated with more favourable food-related practices among staff.

Effects of a cluster randomized controlled kindergarten-based intervention trial on vegetable consumption among Norwegian 3-5-year-olds: the BRA-study

Background

Early childhood represents a critical period for the establishment of long-lasting healthy dietary habits. Limited knowledge exists on how to successfully increase vegetable consumption among preschool children. The overall aim of the present study was to improve vegetable intake among preschool children in a kindergarten-based randomized controlled trial.

Methods

The target group was preschool children born in 2010 and 2011, attending public or private kindergartens in two counties in Norway. Data about child intake of vegetables were collected by three methods. First, parents filled in a web-based questionnaire of the child’s vegetable intake. Second, among a subsample, trained researchers observed children’s vegetable intake in the kindergarten. Thirdly, a parental web-based 24-h recall assessing the child’s vegetable intake was filled in. For allocation of kindergartens to intervention and control groups, a stratified block randomization was used. Multiple intervention components were implemented from September 2015 to February 2016 and components focused at influencing the four determinants availability, accessibility, encouragement and role modelling. The effect of the intervention from baseline (spring 2015) to follow-up 1 (spring 2016) was assessed by mixed-model analysis taking the clustering effect of kindergartens into account.

Results

Parental consent was obtained for 38.8% of the children (633 out of 1631 eligible children). Based on the observational data in the kindergarten setting (n 218 in the control group and n 217 in the intervention group), a tendency to a small positive effect was seen as a mean difference of 13.3 g vegetables/day (95% CI: − 0.2, 26.9) (P = 0.054) was observed.

No significant overall effects were found for the total daily vegetable intake or for the parental reported frequency or variety in vegetable intake.

Conclusions

Based on the observational data in the kindergarten setting, a tendency to a small positive effect was seen with a mean difference of about 13 g vegetables/day, while no other effects on child vegetable intake were found. Additionally, further research to understand the best strategies to involve parents in dietary interventions studies is warranted.

Trial registration

International Standard Randomised Controlled Trials ISRCTN51962956. Registered 21 June 2016 (retrospectively registered).

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7436-3) contains supplementary material, which is available to authorized users.

Means of increasing response rates in a Norwegian dietary survey among infants - results from a pseudo-randomized pilot study

Background

Postal surveys are widely used in scientific studies, including dietary surveys, but few studies about methods to increase participation in national dietary surveys are published. In the present study we compared response rates in a pilot study to a national dietary survey among infants using two different incentives (gift certificate or lottery), personalization in the form of handwritten name and address vs. a printed label and mode of sending out invitations (e-mail or postal invitation).

Methods

In this parallel-design pseudo-randomized pilot trial, a nationally representative sample of 698 mothers of infants aged 6 and 12 months was drawn from the Norwegian National Registry and invited to complete a food frequency questionnaire about their infant’s diet. One half of the mothers of 6 month olds were randomized by alternation to the lottery group (n = 198) and offered to participate in a lottery of two prizes (500 EUR and 1000 EUR). The other half (n = 200) was offered a gift certificate (50 EUR) upon completion of the questionnaire. Each incentive group was randomized by alternation to receiving an invitation with handwritten name and address or a printed label. For the mothers of infants aged 12 months (n = 300), 150 mothers received an e-mail invitation and 150 mothers received a postal invitation. Logistic regression was used for testing differences between the groups.

Results

The response rate was significantly higher (p = 0.028) in the gift certificate group (72%) than in the lottery group (62%). No difference was seen between those receiving an invitation with a handwritten name and address (68%) compared to a printed label (66%, p = 0.72). A somewhat higher response rate was seen when using the postal (50%) compared to the e-mail invitation (43%, p = 0.25).

Conclusions

In this pseudo-randomized parallel-design trial of women participating in a national dietary survey among infants, the response rate was higher when offered a gift certificate than when participating in a lottery. Handwritten name and address did not affect participation compared to a printed label. Only a moderate difference was seen between the postal and e-mail invitation. Others conducting similar methodological studies are encouraged to publish their results to expand the knowledge basis in this area.

Is the environment in kindergarten associated with the vegetables served and eaten? The BRA Study

Aim: The aim of the present study was to explore the associations between the economic, political, sociocultural and physical environments in kindergartens, along with the frequency and variety of vegetables served, and the amount of vegetables eaten. Method: The BRA Study collected data through two paper-based questionnaires answered by the kindergarten leader and pedagogical leader of each selected kindergarten, and a five-day vegetable diary from kindergartens (n = 73) in Vestfold and Buskerud Counties, Norway. The questionnaires assessed environmental factors, and the frequency and variety of vegetables served. The non-parametric Mann–Whitney U and Kruskal–Wallis tests were used to explore the associations between factors in the kindergarten environments and vegetables served and eaten. Results: Kindergartens that included expenditures for food and beverages in the parental fees served a larger variety of vegetables (p = 0.046). A higher frequency of served vegetables (p = 0.014) and a larger amount (p = 0.027) of vegetables eaten were found in kindergartens where parents paid a monthly fee of 251 NOK or more. Similarly, the amount of vegetables eaten was higher (p = 0.017) in kindergartens where the employees paid a monthly fee to eat at work. Furthermore, a larger amount (p = 0.046) of vegetables was eaten in kindergartens that had written guidelines for food and beverages that were offered. Conclusions: This study indicates that the economic environment in a kindergarten seems to be positively associated with the vegetables served and eaten there. This is of high relevance for public health policy as vegetable consumption is an important factor in reducing the risk of non-communicable diseases.

Associations between sociocultural home environmental factors and vegetable consumption among Norwegian 3-5-year olds: BRA-study

The home environment is the first environment to shape childhood dietary habits and food preferences, hence greater understanding of home environmental factors associated with vegetable consumption among young children is needed. The objective has been to examine questionnaire items developed to measure the sociocultural home environment of children focusing on vegetables and to assess the psychometric properties of the resulting factors. Further, to explore associations between the environmental factors and vegetable consumption among Norwegian 3-5 year olds. Parents (n 633) were invited to participate and filled in a questionnaire assessing the child's vegetable intake and factors potentially influencing this, along with a 24-h recall of their child's fruit and vegetable intake. Children's fruit and vegetable intakes at two meals in one day in the kindergarten were observed by researchers. Principal components analysis was used to examine items assessing the sociocultural home environment. Encouragement items resulted in factors labelled "reactive encouragement", "child involvement" and "reward". Modelling items resulted in the factors labelled "active role model" and "practical role model". Items assessing negative parental attitudes resulted in the factor labelled "negative parental attitudes" and items assessing family pressure/demand resulted in the factor labelled "family demand". The psychometric properties of the factors were for most satisfactory. Linear regression of the associations between vegetable intake and the factors showed, as expected, generally positive associations with "child involvement", "practical role model" and "family demand", and negative associations with "negative parental attitudes" and "reward". Unexpectedly, "reactive encouragement" was negatively associated with vegetable consumption. In conclusion, associations between sociocultural home environmental factors and children's vegetable consumption showed both expected and unexpected associations some of which differed by maternal education - pointing to a need for further comparable studies.

Effect of changes in a food frequency questionnaire: comparing data from two national dietary survey instruments among 12-month-old infants

BACKGROUND

National dietary surveys among Norwegian 12-months olds have been conducted twice: in 1999 and 2007. At both time-points diet were assessed by a semi-quantitative food frequency questionnaire (SFFQ) (the SFFQ-1999 and the SFFQ-2007). Modifications in the SFFQ-2007 compared to the SFFQ-1999 have been made; therefore, the objective of the present study has been to explore the comparability of the data obtained by the two questionnaires. Moreover, reliability of maternal recall of infant feeding practices was assessed.

METHODS

Three hundred Norwegian infants born in April 2007 were invited to participate by completing both the SFFQ-1999 and the SFFQ-2007. An invitation letter and one of two questionnaires were sent by mail to the mother/parents about two weeks before the child turned 12 months of age. The study had a cross-over design where half of the sample received the SFFQ-1999 first and then about 2-3 weeks later they received the SFFQ-2007. The second half received the SFFQ-2007 first, and then 2-3 weeks later they received the SFFQ-1999.

RESULTS

Ninety three participants completed both questionnaires (SFFQ-1999 and SFFQ-2007). For nutrients, the largest significant differences between the questionnaires were found for intake of vitamin D and added sugar, where added sugar was reported lower and vitamin D was reported higher with the SFFQ-2007 compared to the SFFQ-1999. For food items, lower intake of yoghurt and higher intake of vegetables and fish were observed with the SFFQ-2007 compared to the SFFQ-1999. In addition, reliable answers with regard to breastfeeding status, age for breastfeeding cessation and age for introducing solid foods were found.

CONCLUSION

There was reasonable comparability between the two questionnaires for most nutrients and foods. The differences between the two questionnaires could mainly be explained by modifications that had occurred over time, where changes in the food composition databases used and especially changes in commercial recipes with regard to baby food products seemed to be of major importance. The differences are important to take into account when interpreting dietary trends among Norwegian 12 month-olds in the period from 1999 to 2007. This study also implies that maternal recall of infant feeding practices is reliable.