The Swiss iodized salt program provides adequate iodine for school children and pregnant women, but weaning infants not receiving iodine-containing complementary foods as well as their mothers are iodine deficient.

BACKGROUND: If children and pregnant women in the population are iodine sufficient, it is generally assumed infants are also sufficient. But weaning infants may be at risk of iodine deficiency because iodized salt contributes little dietary iodine during this period. To fill this gap, iodine fortification of infant formula milk (IFM) and complementary foods (CF) is likely important. OBJECTIVES: The objective of the study was to first confirm that Swiss school children and pregnant women remain iodine sufficient and then to assess iodine status in infancy and the relative contribution of breast milk and IFM/CF to their iodine intakes. METHODS: We measured urinary iodine concentrations (UIC) in national cross-sectional samples of: 1) pregnant women (n=648); 2) school children (n=916); 3) infants at three time points: at 3-4 d after birth and at 6 and 12 months (n=875); and 4) breast-feeding mothers (n=507). We measured breast milk iodine concentrations in the mothers, assessed iodine sources in infant diets, and analyzed iodine content of commercial IFM/CFs (n=22) and salt samples from the school children's households (n=266). RESULTS: Median (m) UICs in pregnant women (162 µg/liter) and school children (120 µg/liter) were sufficient, and 80% of the household salt was adequately iodized (≥15 ppm). However, mUICs in infants not receiving IFM/CF were not sufficient: 1) mUIC in breast-fed infants (82 µg/liter) was lower than in non-breast-fed infants (105 µg/liter) (P<0.001) and 2) mUIC in breast-fed weaning infants not receiving IFM/CF (70 µg/liter) was lower than infants receiving IFM (109 µg/liter) (P<0.01). mUIC was low in lactating mothers (67 µg/liter) and median breast milk iodine concentration was 49 µg/kg. CONCLUSIONS: In countries in which iodized salt programs supply sufficient iodine to older children and pregnant women, weaning infants, particularly those not receiving iodine-containing IFM, may be at risk of inadequate iodine intakes.

Stabilization of the prevalence of childhood obesity in Switzerland.

BACKGROUND: The prevalence of childhood obesity is increasing rapidly in most industrialised countries, but several countries, including Switzerland, have recently reported a levelling off or even a reversal of this alarming trend. STUDY AIM: Our aim was to evaluate the prevalence of childhood obesity in a national sample of Swiss school children recruited to assess iodine nutrition and with this to reconfirm a recently shown stabilising trend. DESIGN: Using a probability-proportionate-to-size cluster sampling, 6 to 12 year old children (n = 907) were recruited in a study of iodine status in Switzerland. Height and weight were measured and body mass index calculated in all children. RESULTS: The prevalence of overweight detected was 12.5% (SE = 1.6) in boys and 12.8% (1.6) in girls while 6.2% (1.1) of boys and 4.2% (0.9) of girls were classified as obese. The highest prevalence of overweight and obesity were found in the Southern region and in bigger cities (>100000 inhabitants). Compared to the most recent national study in 2007, the prevalence was slightly higher, but the differences were not significant, suggesting negative sampling bias does not strongly affect surveys of paediatric adiposity in Switzerland. CONCLUSION: This present study clearly confirms the stabilisation of the prevalence of childhood overweight and obesity in Switzerland.