With data from the WLH and NOWAC studies, we were the first to prospectively study risk factors of melanoma, including estimates for solarium use and melanoma risk (Veierød et al, 2003; Veierød et al., 2010; Ghiasvand et al., 2017). We also study sunscreen habits in relation to melanoma (Ghiasvand et al., 2014; Ghiasvand et al., 2016; Rueegg et al., 2018), melanoma risk on different body sites (Ghiasvand et al., 2019) and solarium use and squamous cell carcinoma (Veierød et al., 2014; Lergenmuller et al., 2019).
In collaboration with the Norwegian Radiation and Nuclear Safety Authority we have studied spectral UVB and UVA solarium irradiances and documented that these are 0.5-3.7 and 3-26 times, respectively, higher than from Oslo summer sun (Nilsen et al., 2011; Nilsen et al., 2012; Nilsen et al., 2016).
In collaboration with the Cancer Registry of Norway we are studying skin cancer incidence and mortality (Robsahm et al. 2015), prognostic factors after melanoma diagnosis (Helsing et al., 2016; Robsahm et al., 2018) and errors in Breslow thickness reporting (Veierød et al., 2018).
In NOWAC, we have studied measurement errors in self-reported melanoma risk factors (Veierød et al., 2008; Parr et al., 2009), compared methods for handling missing data in food frequency questionnaires (Parr et al., 2008), and studied meat intake and cooking methods in relation to colorectal cancer risk (Parr et al. 2013). UV exposure, via its effects on vitamin D synthesis, might have beneficial effects on several conditions including cancer, and we are studying potential positive aspects of UV exposure (Veierød et al., 2010; Edvardsen et al., 2011; Yang et al., 2011).
The properties of the gestational diet have become increasingly associated with consequences for the future health of the offspring. In the MoBa study, we have assessed dietary intake, as well as demographic profile and lifestyle factors, in relation to nausea and vomiting in pregnancy (Chortatos et al., 2013; Chortatos et al., 2015; Chortatos et al., 2018).
The association between BMI and colon cancer is established. In the Norwegian County Study we have studied differences between genders and colon subsites, and also whether weight changes (e.g. weight reduction in the overweight) influence colon cancer risk (Laake et al., 2010) and prognosis (Laake et al., 2016). In this cohort, we have also studied the effects of trans fatty acid intake on cancer risk and CVD mortality (Laake et al., 2012; Laake et al., 2013).
Oral glucose tolerance tests (OGTT) are important in medical care and research, but often studied by simple summary measures. We have extracted information inherent in the shape of OGTT curves, compared it with the information from simple summary measures, and explored the clinical usefulness of such information (Frøslie et al., 2013; Frøslie et al., 2014).
In collaboration with NIPH, we have developed a cardiovascular disease (CVD) risk model, NORISK (Selmer et al., 2008), that is implemented in the Norwegian guidelines for CVD prevention (Norwegian Directorate of Health, 2009 (in Norwegian)) and available as a risk calculator (in Norwegian).