Association of obesity and diabetes with thyroid nodules.

AIM: There are conflicting data concerning the possibility that obesity and diabetes raise the risk of thyroid nodules. The incidence of thyroid nodules is increasing, as is that of obesity and diabetes; therefore, understanding whether these metabolic and nutritional disorders influence nodular thyroid disease is important for organizing prevention strategies. This study investigated the association between thyroid nodules, obesity, diabetes, and dietary habits. MATERIALS AND METHODS: A cohort of randomly selected adults (455 males, 746 females; age: 18-90 years) living in Palermo (Italy), a mild iodine deficiency area, was cross-sectionally investigated. Participants underwent high-resolution ultrasonographic evaluation of the thyroid, and answered a food frequency questionnaire. Laboratory blood measurements were obtained in 587 participants. RESULTS AND DISCUSSION: Thyroid nodules were detected in 475 (39.5%) participants. The number of thyroid nodules was correlated with age (r = 0.19; P < 0.001), gender (r = 0.08; P = 0.005), and body mass index (r = 0.07; P = 0.02). No significant correlation was observed between the number of nodules and glycated hemoglobin, serum insulin concentrations, and homeostasis model assessment of insulin resistance. Age-adjusted and gender-adjusted prevalence of both overweight/obesity and type 2 diabetes of each group of participants divided according to the number of nodules significantly increased with the number of nodules (P < 0.05 in both cases). The group of participants with nodules exhibited a significantly lower age-adjusted and gender-adjusted habitual intake of milk (P = 0.02). Multivariate regression analysis showed that age, gender, body mass index, diabetes, and habitual consumption of milk were independently correlated with presence of thyroid nodules. CONCLUSION: This study seems to indicate that an association exists between obesity, diabetes, and thyroid nodules.

Validation of a food frequency questionnaire for use in Italian adults living in Sicily.

The objective of this study was to validate two interviewer-led food frequency questionnaires (FFQs) of very different lengths: a medium-length FFQ (medium-FFQ) of 36 items and a short-length FFQ (short-FFQ) of 18 items, intending to measure levels of intakes in a local population. Both FFQs were validated against intakes derived from a 3-day dietary record (3-day DR). Sixty-five non-diabetic adults with no known cardiovascular, renal or other systemic diseases were included. High correlation coefficients between the FFQ and the 3-day DR (0.45-0.73) were observed for energy intake, carbohydrates and lipid and protein intake. Bland-Altman plots showed good agreement between the methods. Low (0.26-0.37) correlation coefficients of the different nutrient intakes obtained with the short-FFQ and the 3-day DR were observed, with the exception of alcohol intake (rho = 0.49). This study showed promising evidence for the use of a medium-FFQ as a potentially useful tool for investigating the relationship between habitual diet and diseases in clinical and research settings.

Endothelial function and serum concentration of toxic metals in frequent consumers of fish.

BACKGROUND: Endothelial dysfunction is involved in the pathogenesis of atherosclerosis. Consumption of fish is associated with reduced cardiovascular risk, but there is paucity of data concerning its effect on endothelial function. Furthermore, investigation of the effects of fish consumption on health must take into account the ingestion of contaminants, including transition metals and some metalloids, which may have unfavorable effects on health, including those on the cardiovascular system. We investigated the association between fish consumption, endothelial function (flow mediated dilation of the brachial artery), and serum concentration of some toxic metals in apparently healthy people. METHODS: Twenty-nine high fish consumers (at least 3 portions a week) were compared with 25 low fish consumers (less than 1 portion a week). All participants were free of diabetes, cardiovascular or other systemic diseases. Serum metal (antimonium, arsenic, mercury, lead, cobalt, copper, zinc, selenium, strontium) concentrations were measured in subgroups of 24 high fish consumers and 19 low fish consumers. RESULTS: Both groups exhibited similar habitual dietary patterns, age and anthropometric characteristics. The high fish consumers had higher flow mediated dilation (9.7 ± 1.8 vs. 7.3 ± 1.9%; P<0.001), but also higher serum concentrations of mercury (5.87 ± 2.69 vs. 1.65 ± 1.10 mcg/L; P<0.001) and arsenic (6.04 ± 3.25 vs. 2.30 ± 1.58 mcg/L; P<0.001). The fasting plasma glucose concentrations were significantly correlated with both mercury (r = 0.39; P = 0.01) and arsenic concentrations (r = 0.55; P<0.001). CONCLUSIONS: Habitual consumption of high amounts of fish is associated with better endothelial function despite higher serum concentrations of mercury and arsenic.