The objective of this study was to assess a circadian variation of diet-induced thermogenesis (DIT) that could favor weight gain among night workers used to eating a night time snack. Nine young men were given the same mean at 0900, 1700, or 0100. Energy expenditure was measured by indirect calorimetry 1 h before and during the 6 h after the snack. DIT was calculated as the 3 h of energy expenditure above basal metabolic rate. Morning DIT was significantly higher than afternoon DIT (P = 0.04) and night DIT (P = 0.002). Afternoon DIT was higher than night DIT (P = 0.06). We conclude that the time when a meal is consumed affects the thermogenic response and must be considered in the energy balance.

A prospective computed tomographic (CT) study was performed to determine the prevalence of lung changes in smokers. The study group comprised 175 healthy adult volunteers (current smokers, n = 98; ex-smokers, n = 26; nonsmokers, n = 51). The subjects underwent clinical examination, pulmonary function tests, chest radiography, and conventional and high-resolution CT (HRCT). Significant differences between current smokers, ex-smokers, and nonsmokers were observed with HRCT in the identification of subpleural (P = .11) and parenchymal (P < .001) micronodules, emphysema (P < .001), and areas of ground-glass attenuation (P = .0001). All subjects had normal pulmonary function. Parenchymal micronodules, areas of ground-glass attenuation, and emphysema were observed with a significant predominance in the upper lung zones (P < .01). Presence of emphysema and abnormal bronchial wall thickening were the only HRCT signs associated with significantly lower values of functional parameters. These data support the concept that parenchymal abnormalities can be detected in healthy smokers with normal findings at chest radiography and pulmonary function tests.

Emphysema and/or ground-glass attenuation are linked with impairment of ventilatory lung function over time in persistent current smokers.

In this standardised multicentre European study Karasek's DC model showed large gender and occupational differences whereas geographic region explained a small fraction of the total DC variance, notwithstanding large differences in labour market and working conditions as pointed out by the European Commission as recently as 2000.

Whereas a significant relationship was observed between segmental and lobar air trapping and cigarette consumption, lobular air trapping was not found to reflect functional impairment at the small-airways level.