Laufey Steingrimsdottir

Few studies exist on eating attitudes and well-being of adults in Iceland. In most Western societies great emphasis is placed on a lean and fit body, nevertheless the number of people gaining weigt keeps increasing. Such circumstances may cause discomfort related to food and food choice. The aim of this study was to examine attitudes towards food and eating among Icelandic adults. We used data from the Icelandic national health survey of 5,861 adults, age 18-79, conducted in 2007. A numerical assessment tool for measuring eating attitude was established, based on answers to questions on eating attitude. We used binary regression models to estimate odds ratios (ORs) for unhealthy eating attitude according to different demographic factors. The prevalence of unhealthy eating attitude according to the measurement tool used in the study was 17% among participants, 22% for women and 11% for men. Unhealthy eating attitude was most prevalent in the age-group 18-29 years (36% of women, 15% of men), among those dissatisfied with their body weight (35% of women, 22% of men) and among those defined as obese (38% of women, 23% of men). Our data show that women are more prone to express unhealthy eating attitude compared to men. Those of younger age, with weight dissatisfaction and with high body mass index are positively associated with unhealthy eating attitude, irrespective of gender. Diet, Dietary restraint, Public Health, Eating attitude, Body weight satisfaction. Correspondence: Laufey Steingrimsdottir, laufey@hi.is.

High serum 25-hydroxyvitamin D (25(OH)D) levels have been observed in infants in Nordic countries, likely due to vitamin D supplement use. Internationally, little is known about tracking vitamin D status from infancy to childhood. Following up 1-year-old infants in our national longitudinal cohort, our aims were to study vitamin D intake and status in healthy 6-year-old Icelandic children (n = 139) and to track vitamin D status from one year of age. At six years, the mean 25(OH)D level was 56.5 nmol/L (SD 17.9) and 64% of children were vitamin D sufficient (25(OH)D ≥ 50 nmol/L). A logistic regression model adjusted for gender and breastfeeding showed that higher total vitamin D intake (Odds ratio (OR) = 1.27, 95% confidence interval (CI) = 1.08–1.49), blood samples collected in summer (OR = 8.88, 95% CI = 1.83–43.23) or autumn (OR = 5.64, 95% CI = 1.16–27.32) compared to winter/spring, and 25(OH)D at age one (OR = 1.02, 95% CI = 1.002–1.04) were independently associated with vitamin D sufficiency at age six. The correlation between 25(OH)D at age one and six was 0.34 (p = 0.003). Our findings suggest that vitamin D status in infancy, current vitamin D intake and season are predictors of vitamin D status in early school age children. Our finding of vitamin D status tracking from infancy to childhood provides motivation for further studies on tracking and its clinical significance.

Cod liver oil is a traditional source of vitamin D in Iceland, and regular intake is recommended partly for the sake of bone health. However, the association between lifelong consumption of cod liver oil and bone mineral density (BMD) in old age is unclear. The present study attempted to assess the associations between intake of cod liver oil in adolescence, midlife, and old age, and hip BMD in old age, as well as associations between cod liver oil intake in old age and serum 25-hydroxyvitamin D (25(OH)D) concentration. Participants of the Age, Gene/Environment Susceptibility–Reykjavik Study (age 66–96 years; n 4798), reported retrospectively cod liver oil intake during adolescence and midlife, as well as the one now in old age, using a validated FFQ. BMD of femoral neck and trochanteric region was measured by volumetric quantitative computed tomography, and serum 25(OH)D concentration was measured by means of a direct, competitive chemiluminescence immunoassay. Associations were assessed using linear regression models. No significant association was seen between retrospective cod liver oil intake and hip BMD in old age. Current intake of aged men was also not associated with hip BMD, while aged women with daily intakes had z-scores on average 0·1 higher, compared with those with an intake of < once/week. Although significant, this difference is small, and its clinical relevance is questionable. Intake of aged participants was positively associated with serum 25(OH)D: individuals with intakes of < once/week, one to six time(s)/week and daily intake had concentrations of approximately 40, 50 and 60 nmol/l respectively (P for trend < 0·001).

Previous Icelandic studies have reported higher prevalence of obesity among women residing outside the capital area but no comparable information is available for men. The aim of this study was to assess diet and body mass index (BMI) of adult men and women residing within and outside the capital area. Participants were 1312 men and women,18-80 years, from a random sample of the national registry, response rate 68.6%. Diet was assessed during years 2010 to 2011 using repeated 24-hour recall, weight and height self-reported. OR of BMI≥25 kg/m2 was calculated according to residence and education. Women≥46 years within the capital area had lower BMI, or 25.7 kg/m2 vs 28.4 kg/m2 p=0.007, and were less likely to have BMI>25 kg/m2, OR=0.64; CI 0.41-1.0 than those outside the area. No difference was found between the areas among men or younger women. Diets outside the capital had higher percentage of total fat compared than inside the capital. Saturated fatty acid (SFA) were 15.7E% vs 13.9E% for men, p<0.001 and 14.8E% vs 14.0E%, p=0.007 for women and trans fatty acids (TFA) were 0.9E% vs 0.7E% p%lt;0.001 and 0.8E% vs 0.7E% p=0.001 for men and women respectively. Women's BMI is less associated with residence than in former Icelandic studies. Men's BMI is not associated with residence. Diets within the capital area are closer to recommended intake compared with diets outside the area.

The objective was to assess the vitamin D status in healthy 12-month-old infants in relation to quantity and sources of dietary vitamin D, breastfeeding and seasons. Subjects were 76 12-month-old infants. Serum levels of 25-hydroxyvitamin D (25(OH)D) ≥ 50 nmol/L were considered indicative of vitamin D sufficiency and 25(OH)D < 27.5 nmol/L as being indicative of increased risk for rickets. Additionally, 25(OH)D > 125 nmol/L was considered possibly adversely high. Total vitamin D at 9–12 months (eight data collection days) included intake from diet and supplements. The mean ± SD of vitamin D intake was 8.8 ± 5.2 μg/day and serum 25(OH)D 98.1 ± 32.2 nmol/L (range 39.3–165.5). Ninety-two percent of infants were vitamin D sufficient and none at increased risk for rickets. The 26% infants using fortified products and supplements never/irregularly or in small amounts had lower 25(OH)D (76.8 ± 27.1 nmol/L) than the 22% using fortified products (100.0 ± 31.4 nmol/L), 18% using supplements (104.6 ± 37.0 nmol/L) and 33% using both (110.3 ± 26.6 nmol/L). Five of six infants with 25(OH)D < 50 nmol/L had no intake of supplements or fortified products from 0 to 12 months. Supplement use increased the odds of 25(OH)D > 125 nmol/L. Breastfeeding and season did not affect vitamin D status. The majority of infants were vitamin D sufficient. Our findings highlight the need for vitamin D supplements or fortified products all year round, regardless of breastfeeding.

The significance of serum 25-hydroxyvitamin D [25(OH)D] concentrations for hip fracture risk of the elderly is still uncertain. Difficulties reaching both frail and healthy elderly people in randomized controlled trials or large cohort studies may in part explain discordant findings. We determined hazard ratios for hip fractures of elderly men and women related to serum 25(OH)D, including both the frail and the healthy segment of the elderly population. The AGES-Reykjavik Study is a prospective study of 5764 men and women, age 66–96 years, based on a representative sample of the population of Reykjavik, Iceland. Participation was 71.8%. Hazard ratios of incident hip fractures and baseline bone mineral density were determined according to serum concentrations of 25(OH)D at baseline. Mean follow-up was 5.4 years. Compared with referent values (50–75 nmol/L), hazard ratios for hip fractures were 2.24 (95% CI 1.63, 3.09) for serum 25(OH)D <30 nmol/L, adjusting for age, sex, body mass index, height, smoking, alcohol intake and season, and 2.08 (95% CI 1.51, 2.87), adjusting additionally for physical activity. No difference in risk was associated with 30–50 nmol/L or ≥75 nmol/L in either model compared with referent. Analyzing the sexes separately, hazard ratios were 2.61 (95% CI 1.47, 4.64) in men and 1.93 (95% CI 1.31, 2.84) in women. Values <30 nmol/L were associated with significantly lower bone mineral density of femoral neck compared with referent, z-scores -0.14 (95% CI −0.27, −0.00) in men and −0.11 (95% CI −0.22, −0.01) in women. Our results lend support to the overarching importance of maintaining serum 25(OH)D above 30 nmol/L for bone health of elderly people while potential benefits of having much higher levels could not be detected.

Association between bone mineral density and bone mineral content in old age and milk consumption in adolescence, midlife, and old age was assessed. The association was strongest for milk consumption in midlife: those drinking milk daily or more often had higher bone mineral density and content in old age than those drinking milk seldom or never.

Introduction: Vitamin D is known to be important for bone health. Still, the significance of serum 25-hydroxy vitamin D concentrations (s-25OHD) for hip fracture risk of the elderly is uncertain. Discordant findings may in part be explained by difficulties of RCTs or large cohort studies to reach both the frail and the healthy elderly. The objectives of this study were to determine the risk of hip fractures of the elderly related to s-25OHD, including both the frail and the healthy. Methods/participants: The AGES-Reykjavik Study is a prospective study of 5764 elderly, age 66–96 years, based on a random sample of the population of Reykjavik, participation 71.8%. Incident hip fractures were related to s-25OHD at baseline, average time to event 3.4 years. BMD was measured by quantitative computed topography. Results: Compared with referent values (50–75 nmol/l), hazard ratios for hip fractures were 2.24 (95% CI 1.63, 3.09) for s-25OHD z-score, or −0.18 (95% CI −0.31, 0.04) in men and −0.13 (95% CI −0.23, −0.03) in women. Conclusions: Our study lends support to the prime importance of keeping s-25OHD above 30–40 nmol/l for lowering hip fracture risk of the elderly. While higher levels may be of some benefit for other health outcomes, the main emphasis should be to ensure sufficient vitamin D to maintain adequate status.

Few studies exist on the validity of food frequency questionnaires (FFQs) administered to elderly people. The aim of this study was to assess the validity of a short FFQ on present dietary intake, developed specially for the AGES-Reykjavik Study, which includes 5,764 elderly individuals. Assessing the validity of FFQs is essential before they are used in studies on diet-related disease risk and health outcomes.

79 Background: Prior evidence suggests that rye consumption may reduce risk of prostate cancer (PCa). Our aim is to study whether consumption of rye bread and oatmeal (sources of lignans and fiber), both in early- and midlife, is associated with risk of PCa. Methods: In 2002 to 2006, 2,268 men, aged 67-96 years, reported their dietary habits in the AGES-Reykjavik cohort study. Dietary habits were assessed retrospectively, for early and midlife using a validated food frequency questionnaire (FFQ). Through linkage to cancer- and mortality registers, we retrieved information on PCa diagnosis and mortality through 2009. We used logistic regression to estimate odds ratios (ORs) for PCa according to rye- and oatmeal consumption, adjusted for possible confounding factors including fish-, fish liver oil-, meat-, and milk intake. Results: Of the 2268 men, 347 had or were diagnosed with PCa during follow-up, 63 with advanced disease (stage 3+ or died of PCa). Daily rye bread consumption in adolescence (vs. less than daily) was associated with a decreased risk of PCa diagnosis (OR 0.78; 95% CI: 0.60, 1.00), and of advanced PCa (OR 0.53; 95% CI: 0.32, 0.93). High intake of oatmeal in adolescence (≥5 vs. ≤4 times/ week) was not significantly associated with risk of PCa diagnosis (OR 1.00; 95% CI: 0.78, 1.29) nor advanced PCa (OR 0.73; 95% CI: 0.41, 1.31). Midlife consumption of rye or oatmeal was not associated with PCa risk. Conclusions: Our data suggest that frequent rye bread consumption in adolescence may be associated with reduced risk of PCa, particularly advanced disease.