This study suggests that serum 25(OH)D concentration is associated with a multitude of sociodemographic, lifestyle and metabolic health factors. Thus, it is possible that such factors confound associations observed between serum 25(OH)D concentration and chronic diseases.

BackgroundPoor sleep tends to be patterned by sociodemographic and socioeconomic factors. The aim of this study was to examine the associations of sociodemographic and socioeconomic factors with sleep duration and insomnia-related symptoms across life course.MethodsWe used cross-sectional Health 2000 Survey (2000–2001) among a total of 5,578 adult Finns, aged 30–79 years, representative of adult Finnish population. Data about sociodemographic and socioeconomic circumstances, insomnia-related symptoms over the previous month as well as average sleep duration were collected by questionnaires. Multinomial logistic regression models were adjusted first for gender and age, second for sociodemographic factors, third additionally for socioeconomic factors, and fourth for all covariates and self-perceived health simultaneously.ResultsOn average 70% of Finnish adults slept 7–8 hours a day. Frequent insomnia-related symptoms were more prevalent among women (14%) than men (10%). Not being married, not having children, having low education, low income, being unemployed, and being a disability retiree were associated with frequent insomnia-related symptoms. Similar factors were associated with short and long sleep duration. However, childhood socioeconomic position was mostly unrelated to sleep in adulthood except parental education had some associations with short sleep duration.ConclusionsDisadvantaged socioeconomic position in adulthood, in particular income and employment status, is associated with poorer sleep. When promoting optimal sleep duration and better sleep quality, families with low incomes, unemployed people, and disability retirees should be targeted.

Summary Objective This prospective study explores whether dieting attempts and previous changes in weight predict changes in body mass index (BMI) and waist circumference (WC). Methods The study was based on the representative Finnish Health 2000 Survey and on its follow‐up examination 11 years later. The sample included 2,785 participants, aged 30–69. BMI and WC were determined at health examinations. Information on dieting attempts and previous changes in weight was collected using a questionnaire including questions on whether participant had tried to lose weight (no/yes), gained weight (no/yes) or lost weight (no/yes) during the previous year. Results At baseline, 32.8% were dieters. Of these, 28.4% had lost weight during the previous year. Dieters had higher BMI and WC than non‐dieters. During the follow‐up, the measures increased more in dieters and in persons with previous weight loss. The mean BMI changes in non‐dieters versus dieters were 0.74 (standard deviation [SD] 2.13) kg/m 2 and 1.06 (SD 2.77) kg/m 2 ( P = 0.002), respectively. The corresponding numbers for those with no previous weight change versus those who had lost weight were 0.65 (SD 2.07) kg/m 2 and 1.52 (SD 2.61) kg/m 2 . The increases in BMI and WC were most notable in dieters with initially normal weight. Conclusions The increases in BMI and WC were greater in dieters than in non‐dieters, suggesting dieting attempts to be non‐functional in the long term in the general population.

Long-term psychotherapy is more effective than short-term therapy during a long follow-up, suggesting the need for a careful evaluation of suitability to short-term therapy. More research on the long-term effects of psychotherapy in large-scale studies is still needed, however.