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Objective: To examine the association between the consumption of green tea, coffee and caffeine and depressive symptoms. Design: Cross-sectional study. Consumption of green tea and coffee was ascertained with a validated dietary questionnaire and the amount of caffeine intake was estimated from these beverages. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale. Multiple logistic regression analysis was performed to compute odds ratios and 95 % confidence intervals for depressive symptoms with adjustments for potential confounders. Setting: Two workplaces in north-eastern Kyushu, Japan, in 2009. Subjects: A total of 537 men and women aged 20-68 years. Results: Higher green tea consumption was associated with a lower prevalence of depressive symptoms. Compared with participants consuming #1 cup/d, those consuming $4 cups green tea/d had a 51 % significantly lower prevalence odds of having depressive symptoms after adjustment for potential confounders, with significant trend association (P for trend 5 0?01). Further adjustment for serum folate slightly attenuated the association. Coffee consumption was also inversely associated with depressive symptoms ($2 cups/d v. ,1 cup/d: OR 5 0?61; 95 % CI 0?38, 0?98). Multiple-adjusted odds for depressive symptoms comparing the highest with the lowest quartile of caffeine consumption was OR 5 0?57 (95 % CI 0?30, 1?05; P for trend 5 0?02). Conclusions: Results suggest that higher consumption of green tea, coffee and caffeine may confer protection against depression.

Objective: Although under-reporting of dietary intake is more common in persons with a high body mass index (BMI), it is not well known whether or not misreporting is selective for different foods (and hence energy and nutrients), particularly in nonWestern populations. We examined misreporting of dietary intake against biomarkers and its relation with BMI in young Japanese women. Design: Cross-sectional study. Subjects: A total of 353 female Japanese dietetic students aged 18-22 years (mean BMI: 21.4 kg/m 2 , mean fat intake: 29.8% of energy). Methods: Misreporting of dietary energy, protein, potassium and sodium (assessed by a self-administered diet history questionnaire) was examined against respective biomarkers (estimated energy expenditure and 24-h urinary excretion). Reporting accuracy was calculated as the ratio of reported intake to that estimated from corresponding biomarkers (complete accuracy: 1.00). Results: Mean reporting accuracy of absolute intake (amount per day) varied considerably (0.86-1.14). Reporting accuracy of absolute intake decreased with increasing BMI (P for trend o0.001). However, no association was observed between reporting accuracy of energy-adjusted values and BMI (P for trend 40.15), indicating that BMI-dependent misreporting was canceled by energy adjustment. This was owing to positive correlation between the reporting accuracy of energy intake and that of absolute intake of the three nutrients (Pearson correlation coefficient: 0.49-0.67, Po0.0001). Conclusions: Although differential misreporting of absolute intake was associated with BMI, differential misreporting of energyadjusted value was not. These findings support the use of energy-adjusted values in the investigation of diet-disease relationships among lean populations with a low-fat intake.

Obesity has been related to increased risk of colon cancer or adenomas, but the epidemiologic findings are not entirely consistent. We examined the relation of not only body mass index (BMI) but also waist-to-hip ratio (WHR) and weight gain to colon adenoma risk in men who received a preretirement health examination at the Japan Self Defense Forces (SDF) Fukuoka and Kumamoto Hospitals during the period from 1995 to 1996. In the series of 803 men at age 47-55 years, 189 cases of colon adenomas and 226 controls with normal total colonoscopy were identified. Weight at 10 years before was ascertained by referring to the recorded data. After allowance for hospital, rank in the SDF, smoking and alcohol use, weight gain over the past 10 years was significantly associated with increased risk of colon adenomas (odds ratio for ≥ ≥ ≥ ≥6 kg versus ≤ ≤ ≤ ≤− − − −2 kg = = = = 2.2; 95% confidence interval 1.0-4.8). High BMI and high WHR were each associated with increased risk, but only WHR was related to the risk independently of weight gain. In particular, weight gain accompanied with a high WHR was associated with a significant increase in the risk. Men with high physical activity tended to have lower risk. Associations with obesity-related variables and physical activity were not materially differential as regards the location and size of adenoma. The findings indicate that weight gain in middle age leading to abdominal obesity increases the risk of colon adenomas, and consequently of colon cancer.

Background: Animal studies suggest the beneficial effect of hardness of diet on body weight and adiposity. No human studies have examined hardness of diet in relation to obesity. Objective: We examined cross-sectional associations of hardness of the habitual diet with body mass index (BMI; in kg/m 2 ) and waist circumference in free-living humans. Design: Subjects were 454 female Japanese dietetic students aged 18 -22 y. Dietary hardness was assessed as an estimate of masticatory muscle activity for the habitual diet (ie, the difficulty of chewing the food). The consumption of a total of 107 foods was estimated by means of a self-administered, comprehensive diet history questionnaire, and masticatory muscle activity during the ingestion of these foods was estimated according to published equations. Waist circumference was measured at the level of the umbilicus. Results: Mean BMI was 21.4 (95% CI: 21.1, 21.6), and mean waist circumference was 73.6 (72.9, 74.3) cm. Mean dietary hardness was 178 (175, 181) mV ⅐ s/1000 kcal. Dietary hardness was not significantly associated with BMI. However, it was negatively associated with waist circumference (P for trend ҃ 0.005). This association remained after adjustment not only for potential confounding factors (P for trend ҃ 0.028) but also for BMI (P for trend ҃ 0.002). Conclusions: Whereas no association between dietary hardness and BMI was seen, increasing dietary hardness was associated with lower waist circumference even after adjustment for BMI in freeliving young Japanese women. This finding could make innovative contributions to the literature and raise issues for future studies regarding diet and obesity.Am J Clin Nutr 2007;86:206 -13. KEY WORDSHardness of diet, body mass index, waist circumference, Japanese, women, diet history questionnaire, epidemiology