The effectiveness of prenatal lifestyle intervention to prevent gestational diabetes and improve maternal glucose metabolism remains to be established. The Norwegian Fit for Delivery (NFFD) randomized, controlled trial studied the effect of a combined lifestyle intervention provided to a general population, and found significantly lower gestational weight gain among intervention participants but no improvement in obstetrical outcomes or the proportion of large infants. The aim of the present study is to examine the effect of the NFFD intervention on glucose metabolism, including an assessment of the subgroups of normal-weight and overweight/obese participants.
Healthy, non-diabetic women expecting their first child, with pre-pregnancy body mass index (BMI) =19 kg/m2, age = 18 years and a singleton pregnancy of =20 gestational-weeks were enrolled from healthcare clinics in southern Norway. Gestational weight gain was the primary endpoint. Participants (n = 606) were individually randomized to intervention (two dietary consultations and access to twice-weekly exercise groups) or control group (routine prenatal care). The effect of intervention on glucose metabolism was a secondary endpoint, measuring glucose (fasting and 2-h following 75-g glucose load), insulin, homeostatic assessment of insulin resistance (HOMA-IR) and leptin levels at gestational-week 30.
Blood samples from 557 (91.9%) women were analyzed. For the total group, intervention resulted in reduced insulin (adj. Mean diff -0.91 mU/l, p = 0.045) and leptin levels (adj. Mean diff -207 pmol/l, p = 0.021) compared to routine care, while glucose levels were unchanged. However, the effect of intervention on both fasting and 2-h glucose was modified by pre-pregnancy BMI (interaction p = 0.030 and p = 0.039, respectively). For overweight/obese women (n = 158), intervention was associated with increased risk of at least one glucose measurement exceeding International Association of Pregnancy and Diabetes Study Group thresholds (33.7% vs. 13.9%, adj. OR 3.89, p = 0.004).
The Norwegian Fit for Delivery intervention lowered neither glucose levels nor GDM incidence, despite reductions in insulin and leptin. Prenatal combined lifestyle interventions designed for a general population may be unsuited to reduce GDM risk, particularly among overweight/obese women, who may require earlier and more targeted interventions.
ClinicalTrials.gov ID NCT01001689 , registered July 2, 2009, confirmed completed October 26, 2009 (retrospectively registered).
There are not many studies evaluating the long-term effects of fruit and vegetable interventions.
We examined the effects of 1 y of free fruit in elementary school on long-term consumption of fruit, vegetables, and unhealthy snacks, according to sex and educational attainment, 14 y after the intervention period.
In 2001, the baseline survey of the longitudinal cohort, Fruits and Vegetables Make the Marks (FVMM), included 1950 children (mean age: 11.8 y) attending 38 randomly drawn elementary schools from 2 counties in Norway. In the following 10 mo, 9 schools served as intervention schools by participating in the Norwegian School Fruit Program for free, whereas 29 schools served as control schools. A follow-up survey conducted in 2016 included 982 participants (50%) from the original study sample (mean age: 26.5 y). The consumption of fruit and vegetables was measured by a 24-h recall (portions per day), and the consumption of unhealthy snacks was measured by food-frequency questions (portions per week). Linear mixed models were performed to test possible intervention effects on the consumption of fruit, vegetables, and unhealthy snacks 14 y after the intervention period.
No overall intervention effects after 14 y due to the free-fruit scheme on the consumption of fruit, vegetables, and unhealthy snacks were observed, but significant interactions showed a sustained higher frequency of fruit consumption among females in the intervention group compared with the control group [mean difference (MD): 0.38 portions/d; P = 0.023] and that this effect was only significant among less-educated females (MD: 0.73 portions/d; P = 0.043). No significant long-term intervention effects were observed in the consumption of fruit among highly educated females and males nor in the consumption of vegetables or unhealthy snacks.
Results from the present study indicate that receiving free fruit at school for 1 y may have positive long-term effects for females without higher education.
CommentIn: Am J Clin Nutr. 2019 Jan 1;109(1):5-6 PMID 30624574
A diet high in fruit and vegetables (FV) is inversely related to chronic diseases, and some studies suggest that increasing the intake of FV reduces the intake of unhealthy snacks.
The objectives were to analyze changes in the frequency of consumption of unhealthy snacks (soda, candy, and potato chips) from 2001 to 2008 in Norwegian children, to assess whether being part of a school fruit program reduces the frequency of unhealthy snack consumption, and to explore differences in sex and socioeconomic status.
Within the project Fruits and Vegetables Make the Marks, 1488 sixth- and seventh-grade pupils from 27 Norwegian elementary schools completed a questionnaire in 2001, and 1339 sixth- and seventh-grade pupils from the same schools completed the same questionnaire in 2008. In 2001, none of the schools had any organized school fruit program. In 2008, 15 schools participated in a program and 12 did not participate in any program.
From 2001 to 2008, the frequency of unhealthy snack consumption decreased from 6.9 to 4.6 times/wk (P
It is important that health-promoting efforts result in sustained behavioural changes, preferably throughout life. However, only a very few intervention studies evaluate long term follow up.
The aim of the present study is to evaluate the overall and up to seven years effect of providing daily one piece of fruit or vegetable (FV) for free for one school year.
A total of 38 randomly drawn elementary schools from two counties in Norway participated in the Fruit and Vegetables Make the Marks project. Baseline (2001) and follow-up surveys were conducted in May 2002, 2005 and 2009 (n?=?320 with complete data) to assess FV and unhealthy snack intake. Mixed models were used to analyze the data.
Statistically significant adjusted overall effects of the intervention were revealed for FV intake (1.52 times/day) but this weakened over time. A significant adjusted overall effect (-1.54 consumptions/week) and a significant seven-year-follow-up effect (-2.02 consumptions/week) was found for consumption of unhealthy snacks for pupils of parents without higher education.
One year of free school fruit resulted in higher FV intake and lower unhealthy snack intake, however this weakened over time for FV intake and became stronger for snack intake. More follow-up studies with larger samples and lower attrition rates are needed in order to further evaluate the long-term effect.
Cites: Health Educ Res. 2006 Apr;21(2):258-6716219631