Studies on the association between heavy coffee consumption and risk of less frequently diagnosed cancers are scarce. We aimed to quantify the association between filtered, boiled, and total coffee consumption and the risk of bladder, esophageal, kidney, pancreatic, and stomach cancers. We used data from the Norwegian Women and Cancer Study and the Northern Sweden Health and Disease Study. Information on coffee consumption was available for 193,439 participants. We used multivariable Cox proportional hazards models to calculate hazard ratios (HR) with 95% confidence intervals (CI) for the investigated cancer sites by category of total, filtered, and boiled coffee consumption. Heavy filtered coffee consumers (= 4 cups/day) had a multivariable adjusted HR of 0.74 of being diagnosed with pancreatic cancer (95% CI 0.57-0.95) when compared with light filtered coffee consumers (= 1 cup/day). We did not observe significant associations between total or boiled coffee consumption and any of the investigated cancer sites, neither in the entire study sample nor in analyses stratified by sex. We found an increased risk of bladder cancer among never smokers who were heavy filtered or total coffee consumers, and an increased risk of stomach cancer in never smokers who were heavy boiled coffee consumers. Our data suggest that increased filtered coffee consumption might reduce the risk of pancreatic cancer. We did not find evidence of an association between coffee consumption and the risk of esophageal or kidney cancer. The increased risk of bladder and stomach cancer was confined to never smokers.
The association between milk and dairy intake and the incidence of cardiometabolic diseases, cancer and mortality has been evaluated in many studies, but these studies have had conflicting results with no clear conclusion on causal or confounding associations. The present study aims to further address this association by cross-sectional and longitudinal evaluation of the associations between exposure to various types of dairy products and metabolic risk markers among inhabitants in northern Sweden while taking other lifestyle factors into account.
Respondents in the Västerbotten Intervention Programme with complete and plausible diet data between 1991 and 2016 were included, yielding 124,934 observations from 90,512 unique subjects. For longitudinal analysis, 27,682 participants with a visit 8-12?years after the first visit were identified. All participants completed a validated Food Frequency Questionnaire. Metabolic risk markers, including body mass index (BMI), blood pressure, serum (S) cholesterol and triglycerides, and blood glucose, were measured. Participants were categorized into quintiles by intake of dairy products, and risk (odds ratios, OR) of undesirable levels of metabolic risk markers was assessed in multivariable logistic regression analyses. In longitudinal analyses, intake quintiles were related to desirable levels of metabolic risk markers at both visits or deterioration at follow-up using Cox regression analyses.
The OR of being classified with an undesirable BMI decreased with increasing quintiles of total dairy, cheese and butter intake but increased with increasing non-fermented milk intake. The OR of being classified with an undesirable S-cholesterol level increased with increasing intake of total dairy, butter and high fat (3%) non-fermented milk, whereas an undesirable S-triglyceride level was inversely associated with cheese and butter intake in women. In longitudinal analyses, increasing butter intake was associated with deterioration of S-cholesterol and blood glucose levels, whereas increasing cheese intake was associated with a lower risk of deterioration of S-triglycerides.
Confounding factors likely contribute to the demonstrated association between dairy intake and mortality, and other medical conditions and analyses should be stratified by dairy type.