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.

Discretionary foods and drinks in Norwegian children and adolescents' diet: data from the national dietary survey Ungkost 3

OBJECTIVE

This study aimed to identify the amount of discretionary foods and drinks consumed by Norwegian children and adolescents, describe how such products contribute to the intake of total energy and nutrients, and study the distribution in intake of discretionary foods and drinks across different meals. Secondly, the aim was to explore factors associated with those children and adolescents having the highest consumption of discretionary foods and drinks.

DESIGN

Secondary analysis of data from a national survey of dietary intake among Norwegian children and adolescents.

SETTING

Schools in fifty randomly selected municipalities in Norway.

PARTICIPANTS

The study population included 636 pupils in 4th grade (9-11 years) and 687 pupils in 8th grade (12-14 years).

RESULTS

Discretionary foods and drinks contributed to about 20 % of the children and adolescents' total energy intake. These products contributed to about two-thirds of the participants' intake of added sugar, and limited amounts of dietary fibre, vitamins and minerals. The quartile which had the lowest proportion of their energy intake from discretionary foods and drinks seemed to have a higher intake of whole grains, and fish and seafood.

CONCLUSIONS

Almost all 4th and 8th graders in Norway consumed discretionary foods and drinks, and these products contributed to a substantial proportion of the total energy intake and limited amounts of nutrients. Those children and adolescents consuming the least discretionary foods and drinks had a higher intake of whole grains, fish and seafood, indicating healthier and more sustainable food habits.

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.

Validation of energy intake recorded by a 7-day pre-coded food diary against measured energy expenditure in a group of Norwegian adults

The aim of this study was to validate energy intake (EI) reported by a pre-coded food diary (PFD) against energy expenditure (EE) measured by the ActiReg system consisting of an activity and position monitor and a calculation program (ActiCalc). Dietary intake was recorded by the PFD and EE was measured by the ActiReg system over a 7-day period. One hundred and twenty adult participants completed the study, 42 men and 78 women. The average group EI was 17% lower compared to measured EE. The 95% limits of agreement were 6.7 and -2.9 MJ/day. Of all participants, 68% were classified as acceptable reporters, 29% as underreporters and only 3% as overreporters. Fifty percent of the men and 30% of the women were classified into the same quartile for EI and EE, whereas 5% of both men and women were ranked in the opposite quartile by the two methods (weighted kappa coefficient = 0.29). Pearson correlation coefficient between reported EI and measured EE was 0.49 (p<0.001). High BMI was related to larger underreporting when EE was low. Furthermore, this study found that PFD underestimates EI on the group level with an average of 17% and showed large variation in the validity of the PFD on the individual level.

Diet quality on days without breakfast or lunch - Identifying targets to improve adolescents' diet

Dietary intake in adolescents does often not align with the recommended dietary guidelines. Excess intakes of added sugar and saturated fat, and insufficient vegetable intake are among the identified challenges, which can affect future health negatively. Identifying targets to improve dietary practices is therefore essential. The current study aimed to examine the prevalence of meal skipping and if meal skipping days had a different diet quality than other days, using data from a recent Norwegian dietary survey in adolescents (n = 689, age 12-14 years). Their dietary intake was recorded for four days, using a web-based record system. Differences between days with, and without, breakfast or lunch were explored using mixed effect models, adjusting for correlated data and covariates, including weekday-weekend effect. In total, 8% and 11% were days without breakfast and lunch, respectively. Days with breakfast or lunch were associated with higher intake of fibre, and higher odds of consuming fruits and berries, juice and smoothie, than days without breakfast or lunch. Weekdays with lunch were also associated with lower intakes of added sugar and total fat (in % of energy), and discretionary foods, compared to weekdays without lunch. Skipping breakfast and lunch was associated with reduced diet quality in adolescents. Targeting these meals, and in particular school lunch, is a potential way forward to improve adolescents' dietary intake.

Relative validation of a pre-coded food diary in a group of Norwegian adults - Comparison of underreporters and acceptable reporters

Estimating dietary intake is important for both epidemiological and clinical studies. In large studies, a balance has to be achieved between methods with high accuracy and methods that are easy to use. The aim of the present study was to compare results from a pre-coded scanable food diary (PFD) with results from a weighed record (WR) in a group of Norwegian adults. We also explored differences in day-to-day energy intake and the distribution of energy intake across the day in acceptable reporters (ARs) and underreporters (URs). Participants (n = 114, mean age 35 years, 68% women) recorded dietary intake with the PFD for 7 consecutive days. One week after completing the PFD, participants completed a 7 days WR. No difference in mean energy intake was seen between methods. Few differences were seen for the macronutrients, the most noticeable difference being the percentage of energy (E%) from carbohydrates which was significantly lower with the PFD (47 E%) than with the WR (49 E%). For the micronutrients, intakes of calcium and vitamin A were both significantly higher with the PFD than with the WR. Pearson's correlation coefficient ranged from 0.47 (tocopherol) to 0.76 (E% carbohydrates) for all nutrients. Bread intake was significantly lower with the PFD while the intakes of edible fats, cheese and beverages were higher. Twenty-eight percent of the participants were found to be URs with the PFD. No clear pattern of underreporting at certain recording days or times of the day was seen. In conclusion, the results showed similar energy intakes and few differences in food and nutrient intakes between the PDF and the WR at the group level. Somewhat larger differences between the methods were seen at the individual level. Because of the reduced work load on both participants and researchers, the PFD seems a suitable alternative to the WR.

Differences in nutrient composition and choice of side dishes between red meat and fish dinners in Norwegian adults

BACKGROUND

Food-based dietary guidelines often recommend increased consumption of fish and reduced intake of red and processed meat. However, little is known about how changing the main protein source from red meat to fish may influence the choice of side dishes.

OBJECTIVE

To investigate whether side dish choices differed between red meat and fish dinners. Moreover, to compare intakes of macronutrients and selected micronutrients in red meat and fish dinners and to see whether whole-day intakes of these nutrients differed between days with red meat dinners and days with fish dinners.

DESIGN

Data were collected in a cross-sectional nationwide Norwegian dietary survey using two non-consecutive telephone-administered 24-h recalls. The recalls were conducted approximately 4 weeks apart. In total, 2,277 dinners from 1,517 participants aged 18-70 were included in the analyses.

RESULTS

Fish dinners were more likely to include potatoes and carrots than red meat dinners, whereas red meat dinners more often contained bread, tomato sauce, and cheese. Red meat dinners contained more energy and iron; had higher percentages of energy (E%) from fat, saturated fat, and monounsaturated fat; and a lower E% from protein and polyunsaturated fat than fish dinners. Fish dinners contained more vitamin D, β-carotene, and folate than red meat dinners. Similar differences were found when comparing whole-day intakes of the same nutrients on days with red meat versus fish dinners.

CONCLUSION

Fish dinners were accompanied by different side dishes than red meat dinners. With regard to nutrient content, fish dinners generally had a healthier profile than red meat dinners. However, iron intake was higher for red meat dinners. Information about associated foods will be useful both for developing public health guidelines and when studying associations between dietary factors and health outcomes.