Dietary cadmium exposure and the risk of hormone-related cancers

The toxic metal cadmium has been widely dispersed into the environment mainly through anthropogenic activities. Even in industrially non-polluted areas, farmland and consequently foods are, to a varying degree, contaminated. Food is the main source of exposure besides tobacco smoking. Cadmium accumulates in the body, particularly in the kidney where it may cause renal tubular damage. Recently, cadmium was discovered to possess endocrine disrupting properties, mainly mimicking the in vivo- effects of estrogen. The metal is classified as a human carcinogen by the International Agency for Research on Cancer based on lung cancer studies of occupational inhalation. It is, however, not clear whether cadmium exposure via the diet may cause cancer. Possible health consequences related to estrogenic effects such as increased risk of hormone-related cancers are virtually unexplored. The aims of this thesis were to: 1) estimate the dietary exposure to cadmium, 2) estimate cadmium’s toxicokinetic variability using a population model and to establish the link between urinary cadmium concentrations (a biomarker of accumulated kidney cadmium) and the corresponding long-term dietary exposure to cadmium in the population, 3) evaluate the comparability between food frequency questionnaire (FFQ)-based estimates of dietary cadmium exposure and urinary cadmium concentrations and 4) prospectively assess the association between dietary cadmium exposure and incidence of hormone-related cancers (endometrial, breast, ovarian and prostate cancers) in two population-based cohorts consisting of around 60 000 Swedish women and 40 000 men. The main sources of dietary cadmium exposure (~80%) in both women and men were bread and other cereals, potatoes, root vegetables, and other vegetables. A one- compartment toxicokinetic model provided similar predictions of individual urinary cadmium concentrations as a more complex toxicokinetic model. We estimated the cadmium half-life to be about 11.6 years with 25% between-person variability in the population. The Pearson correlation between FFQ-based estimates of dietary cadmium exposure and urinary cadmium concentration was 0.2 and the observed sensitivity and specificity was 58% and 51%, respectively. Estimated dietary cadmium exposure was associated with a statistically significant increased risk of cancer of the endometrium, breast, and prostate (39%, 21% and 13% respectively) – but not with ovarian cancer – comparing the highest tertile of cadmium with the lowest. The risk estimates were higher in lean and normal weight women and men: we observed statistically significant increased risks of 52%, 27% and 49% for endometrial cancer, overall breast cancer and localized prostate cancer, respectively. Never-smoking women with lower endogenous (normal body mass index) and exogenous estrogens (no postmenopausal hormone use) and with a consistently high dietary exposure to cadmium assessed twice, 10 years apart, had a 2.9-fold increased risk of endometrial cancer, which may indicate an estrogenic effect. The highest risk of breast cancer (60% increase) was observed for diets high in cadmium and low in whole grain and vegetables, as compared to diets low in cadmium and high in whole grain and vegetables. Taken together these results indicate that dietary cadmium exposure may play a role in the development of hormone-related cancers

Mediterranean diet and telomere length in Nurses’ Health Study: population based cohort study

Objective: To examine whether adherence to the Mediterranean diet was associated with longer telomere length, a biomarker of aging. Design: Population based cohort study. Setting: Nurses’ Health Study, an ongoing prospective cohort study of 121 700 nurses enrolled in 1976; in 1989-90 a subset of 32 825 women provided blood samples. Participants: 4676 disease-free women from nested case-control studies within the Nurses’ Health Study with telomere length measured who also completed food frequency questionnaires. Main outcome measure Association between relative telomere lengths in peripheral blood leukocytes measured by quantitative real time polymerase chain reaction and Alternate Mediterranean Diet score calculated from self reported dietary data. Results: Greater adherence to the Mediterranean diet was associated with longer telomeres after adjustment for potential confounders. Least squares mean telomere length z scores were −0.038 (SE 0.035) for the lowest Mediterranean diet score groups and 0.072 (0.030) for the highest group (P for trend=0.004). Conclusion: In this large study, greater adherence to the Mediterranean diet was associated with longer telomeres. These results further support the benefits of adherence to the Mediterranean diet for promoting health and longevity

Relation between dietary cadmium intake and biomarkers of cadmium exposure in premenopausal women accounting for body iron stores

<p>Abstract</p> <p>Background</p> <p>Cadmium is a widespread environmental pollutant with adverse effects on kidneys and bone, but with insufficiently elucidated public health consequences such as risk of end-stage renal diseases, fractures and cancer. Urinary cadmium is considered a valid biomarker of lifetime kidney accumulation from overall cadmium exposure and thus used in the assessment of cadmium-induced health effects. We aimed to assess the relationship between dietary cadmium intake assessed by analyses of duplicate food portions and cadmium concentrations in urine and blood, taking the toxicokinetics of cadmium into consideration.</p> <p>Methods</p> <p>In a sample of 57 non-smoking Swedish women aged 20-50 years, we assessed Pearson's correlation coefficients between: 1) Dietary intake of cadmium assessed by analyses of cadmium in duplicate food portions collected during four consecutive days and cadmium concentrations in urine, 2) Partial correlations between the duplicate food portions and urinary and blood cadmium concentrations, respectively, and 3) Model-predicted urinary cadmium concentration predicted from the dietary intake using a one-compartment toxicokinetic model (with individual data on age, weight and gastrointestinal cadmium absorption) and urinary cadmium concentration.</p> <p>Results</p> <p>The mean concentration of cadmium in urine was 0.18 (+/- s.d.0.12) μg/g creatinine and the model-predicted urinary cadmium concentration was 0.19 (+/- s.d.0.15) μg/g creatinine. The partial Pearson correlations between analyzed dietary cadmium intake and urinary cadmium or blood concentrations were r = 0.43 and 0.42, respectively. The correlation between diet and urinary cadmium increased to r = 0.54 when using a one-compartment model with individual gastrointestinal cadmium absorption coefficients based on the women's iron status.</p> <p>Conclusions</p> <p>Our results indicate that measured dietary cadmium intake can reasonably well predict biomarkers of both long-term kidney accumulation (urine) and short-term exposure (blood). The predictions are improved when taking data on the iron status into account.</p

Front-of-Pack Nutrition Labels: Comparing the Nordic Keyhole and Nutri-Score in a Swedish Context

The extent to which different front-of-pack nutrition labels (FOPNLs) agree or contradict each other has been insufficiently investigated. Considering the 2020 proposal from the European Commission to create a harmonized FOPNL, the aim of this study was to assess agreements and disagreements between two FOPNL schemes&mdash;the Keyhole and the Nutri-Score&mdash;in a Swedish context. The current Keyhole criteria and the updated Nutri-Score 2022 algorithm were applied to 984 food items and their nutrient compositions, obtained from the food database of the Swedish Food Agency. Agreements (Keyhole-eligible and Nutri-Score A or B; or not Keyhole-eligible and Nutri-Score C, D, or E) and disagreements (Keyhole-eligible and Nutri-Score C, D, or E, or not Keyhole-eligible and Nutri-Score A or B) were calculated as percentages for all items and by food group. An agreement was found for 81% of included items. The lowest level of agreement was found for the groups of flour, grains, and rice (62% agreement) and for plant-based meat and fish analogues (33% agreement). There is generally a good level of agreement between the Keyhole and the Nutri-Score for food items on the Swedish market. Large disagreements found for plant-based meat and fish analogues, and products based on cereals/grains, highlight important considerations for the development of a harmonized FOPNL within Europe

Association between sociodemographic determinants and health outcomes in individuals with type 2 diabetes in Sweden

BACKGROUND: Concurrent multifactorial treatment is needed to reduce consequent risks of diabetes, yet most studies investigating the relationship between sociodemographic factors and health outcomes have focused on only one risk factor at a time. Swedish health care is mainly tax-funded, thus providing an environment that should facilitate equal health outcomes in patients, independent of background, socioeconomic status or health profile. This study aimed at investigating the association between several sociodemographic factors and diabetes-related health outcomes represented by HbA1c , systolic blood pressure, LDL cholesterol, predicted 5-year risk of cardiovascular disease as well as statin use. METHODS: This large retrospective registry-study was based on patient-level data from individuals diagnosed with type 2 diabetes mellitus during 2010-2011 (n = 416,228) in any of seven Swedish regions (~65% of the Swedish population). Health equity in diabetes care was analyzed through multivariate regression analyses on intermediary outcomes (HbA1c , systolic blood pressure, LDL), predicted 5-year risk of cardiovascular disease and process (i.e. statin use) after one-year follow-up, adjusting for several sociodemographic factors. RESULTS: We observed differences in intermediary risk measures, predicted 5-year risk of cardiovascular disease as well as process dependent on place of birth, sex, age, education and social setting, despite Sweden's articulated vision of equal health care. CONCLUSIONS: Diabetes patients' health was associated with sociodemographic prerequisites. In addition to demographics (age, sex) and disease history; educational level, marital status and region of birth are important factors to consider when benchmarking health outcomes, e.g. average HbA1c level, between organizational units or between different administrative regions

Sociodemographic determinants and health outcome variation in individuals with type 1 diabetes mellitus : A register-based study

Background: Socioeconomic status, origin or demographic attributes shall not determine the quality of healthcare delivery, according to e.g. United Nations and European Union rules. Health equity has been defined as the absence of systematic disparities and unwarranted differences between groups defined by differences in social advantages. A study was performed to investigate whether this was applicable to type 1 diabetes mellitus (T1D) care in a setting with universal, tax-funded healthcare. Methods: This retrospective registry-study was based on patient-level data from individuals diagnosed with T1D during 2010-2011 (n = 16,367) in any of seven Swedish county councils (covering -65% of the Swedish population). Health equity in T1D care was analysed through multivariate regression analyses on absolute HbA1c level at one-year follow-up, one-year change in estimated glomerular filtration rate (eGFR) and one-year change in cardiovascular risk score, using selected sociodemographic dimensions as case-mix factors. Results: Higher educational level was consistently associated with lower levels of HbA1c, and so was being married. Never married was associated with worse eGFR development, and lower educational level was associated with higher cardiovascular risk. Women had higher HbA1c levels than men, and glucose control was significantly worse in patients below the age of 25. Conclusion: Patients' sociodemographic profile was strongly associated with absolute levels of risk factor control in T1 D, but also with an increased annual deterioration in eGFR. Whether these systematic differences stem from patient-related problems or healthcare organisational shortcomings is a matter for further research. The results, though, highlight the need for intensified diabetes management education and secondary prevention directed towards T1D patients, taking sociodemographic characteristics into account

Descriptive statistics of study sample at baseline.

<p>Standard deviation in parentheses.</p