The iron status of a national sample of adults living in France and participating in the SU.VI.MAX cohort, was assessed using serum ferritin and hemoglobin concentrations. Complete data were obtained for 6648 women 35 ± 60 y old and for 3283 men 45 ± 60 y old. Assessment of iron dietary intakes was realized on a subsample of 3111 women and 2337 men who reported six 24 h dietary records during a one-year period; 22.7% of menstruating women and 5.3% of post-menopausal women presented a total depletion of iron stores (serum ferritin`15 mgal). Iron-de®cient anemias were found in, respectively, 4.4% and less than 1% of these women. Three-quarters of the anemias were related to iron de®ciency in menstruating women. In men, iron depletion and iron de®ciency anemia were very rare. Post-menopausal women had much higher serum ferritin levels than menstruating women. In menstruating women, those using intrauterine devices had signi®cantly lower serum ferritin levels than those without contraception, and much lower than those using oral contraception. The frequency of iron depletion reached 28.1% in women using intrauterine devices, but only 13.6% in those using oral contraceptives. The mean iron intake was 16.7 AE 5.7 mgad in men and 12.3 AE 3.4 mgad in women. Heme iron represented respectively, 11.1 and 10.4% of iron intake. Ninety-three percent of menstruating women had dietary iron intakes lower than recommended dietary allowances (RDA); 52.6% consumed less than two thirds of these RDA. In post-menopausal women and men, respectively 27.7% and 3.6% had dietary intakes lower than RDA. Serum ferritin was positively correlated with meat, ®sh and total iron intake, and negatively correlated with dietary products consumption, calcium and ®ber intake.

Men are known to be at greater risk of urolithiasis and cardiovascular and renal diseases than women. Previous studies suggest that greater urine concentration is associated with acceleration of progression of chronic kidney disease (CKD), increased urinary albumin excretion, and delayed renal sodium excretion. The present review addresses possible sex-related differences in urine volume and osmolality (U(osm)) that could participate in this male risk predominance. Because of the scarcity of information, we reanalyzed 24-h urine data collected previously by different investigators for other purposes. In nine studies concerning healthy subjects (6 studies) or patients with CKD or diabetes mellitus, U(osm) (or another index of urine concentration based on the urine/plasma creatinine concentration ratio) was 21-39% higher (i.e., about a 150 mosm/kgH2O difference) in men than in women. Urine volume was not statistically different. Thus, the larger osmolar load of men (related to their higher food intake) is excreted in a more concentrated urine with no difference in urine volume. This sex difference was not influenced by the level of sodium excretion and was still present in CKD patients. Sex differences in thirst threshold, AVP level, and other regulatory mediators may all contribute to the higher male U(osm). Because of the previously demonstrated adverse effects of vasopressin and/or high urine concentrating activity, the greater tendency of men to concentrate urine could participate in their greater susceptibility to urolithiasis and hypertension and to the faster progression towards end-stage renal failure.

The state of borderline iodine deficiency observed in France, in association with a slightly goitrogenic environment, may result in sustained stimulation of the thyroid, independently of TSH level, and is of paramount importance in the formation of goitre. Smoking may affect the thyroid, inducing marked long-lasting thyroid enlargement.

Objective: To investigate the relationship between selenium status, thyroid volume and gland echostructure. Design: Cross-sectional. Methods: In 792 men (45-60 years) and 1108 women (35-60 years) from the SU.VI.MAX study, thyroid volume and gland echostructure were determined ultrasonographically. At baseline, thyrotropin, free thyroxine, selenium, zinc, a-tocopherol, b-carotene, retinol, urinary iodine and thiocyanate concentrations were measured. Alcohol consumption, smoking, and menopausal status were assessed by a questionnaire. A stepwise linear and a logistic regression model were used, adjusting for antioxidant vitamins, trace elements status and age. Results: In women, there was an inverse association between selenium status and thyroid volume ðP ¼ 0:003Þ: A protective effect of selenium against goiter (odds ratio ðORÞ ¼ 0:07; 95% confidence interval ðCIÞ ¼ 0:008 -0:6) and thyroid tissue damage ðOR ¼ 0:2; 95% CI ¼ 0:06 -0:7Þ was observed. There was no evidence of an association between menopausal status and other antioxidant elements, thyroid volume or thyroid hypoechogenicity. Smoking, but not alcohol consumption, was associated with an increased risk of thyroid enlargement in women ðOR ¼ 3:94; 95% CI ¼ 1:64 -9:48Þ: No association between thyroid volume, thyroid structure or selenium was found in men. Conclusion: Our findings suggest that selenium may protect against goiter. Selenium was related to thyroid echostructure, suggesting it may also protect against autoimmune thyroid disease.