Regular Coffee Intake Research Articles

Age, Body Mass, Usage of Exogenous Estrogen, and Lifestyle Factors in Relation to Circulating Sex Hormone–Binding Globulin Concentrations in Postmenopausal Women

Circulating concentrations of sex hormone-binding globulin (SHBG) have been associated with cardiovascular diseases, type 2 diabetes, metabolic syndrome, and hormone-dependent cancers; however, correlates of SHBG concentrations are not well understood. We comprehensively investigated correlates of SHBG concentrations among 13 547 women who participated in the Women's Health Initiative and who had SHBG measurements. We estimated study- and ethnicity-specific associations of age, reproductive history, usage of exogenous estrogen, body mass index (BMI), and lifestyle factors such as physical activity, smoking, alcohol consumption, coffee intake, and dietary factors with SHBG concentrations. These estimates were pooled using random-effects models. We also examined potential nonlinear associations using spline analyses. There was no significant ethnic difference in the age-adjusted mean concentrations of SHBG. Age, exogenous estrogen use, physical activity, and regular coffee intake were positively associated with SHBG concentrations, whereas BMI was inversely associated with SHBG concentrations after adjustment for potential confounding factors. Similar patterns were observed among both ever users and never users of exogenous estrogen. The spline analysis indicated nonlinear relations of regular intake of coffee, age, and BMI with SHBG concentrations. Two or more cups/day of regular coffee consumption and age of 60 years or older were associated with higher SHBG concentrations; the inverse BMI-SHBG relation was especially strong among women whose BMI was below 30. In this large sample of postmenopausal women, age, exogenous estrogen use, physical activity, regular coffee intake, and BMI were significant correlates of SHBG concentrations, presenting potential targets for interventions.

Maternal coffee intake and associated risk factors: effects on fetal growth and activity.

Empirical studies have shown that fetal growth and activity can be affected by several risk factors, such as maternal anxiety, depression and tobacco or alcohol consumption. Caffeine intake has received less attention in the literature, as well as the analysis of the mutual interplay of the range of such risk factors. This study aimed to examine effects of mother's coffee intake and associated risk factors during early pregnancy on fetal growth and activity. The sample involved 47 fetuses (51.1% male and 48.9% female) with gestational ages between 20-22 weeks whose mothers were recruited in a Portuguese antenatal obstetric unit. Repeated measures of mother's anxiety (STAI-S) and depression (EPDS) and information about socio-demographics and substances consumption were collected during the first and second trimesters of pregnancy. Fetal activity and biometry were measured during the 2(nd) trimester ultrasound. Results showed that 1) 23.4% of the pregnant women (N = 11) had regular coffee intake; 2) no significant differences were found neither on fetal growth nor on fetal movements considering mother's coffee intake; 3) when mother's socio-demographics and substances consumption were considered, tobacco consumption and anxiety at the 2(nd) trimester appeared as significant predictors of fetal growth and mother's coffee intake and anxiety symptoms at the 2(nd) trimester emerged as significant predictors of fetal movements. An adverse impact of maternal coffee intake during pregnancy was found on fetal activity but not on fetal growth. A deeper understanding of the multiple pathways by which these risk factors affect fetal growth and activity is needed.

Changes of Antioxidant Capacity of Robusta Coffee during Roasting

The <I>in vitro</I> radical scavenging capacity of the roasted and ground coffee is generally known as well as the published results of lowering the incidence of various diseases by regular intake of coffee. The antioxidant capacity of coffee is based mainly on the phenols, but during the roasting phenols are degraded and new products with antioxidant capacity are formed. A major contributor to the antioxidant activity was identified as N-methylpyridinium, which is formed during the roasting by degradation of trigonelline, the degradation is about 50% of trigonelline content and the concentration of N-methylpyridinium in roasted coffee is up to 0.25% on a dry weight basis. These literature data were verified within the processing plant experiment, during the usual roasting procedure of Robusta coffee the following parameters were analysed: humidity, water activity, total antioxidant capacity, total phenols, chlorogenic acid and trigonelline content, and colour <I>(L*, a*, b*</I>). The changes of the evaluated parameters were correlated to each other. During the roasting the total antioxidant capacity (TAC) decreased to about one half of original level in the beginning stages of roasting, another decrease continued during the storage of roasted coffee at about 10% within the year. The degradation of trigonelline, neither the content of chlorogenic acid or total phenols did not correlate with TAC in samples during the roasting and storage.

Regular Coffee Intake is Related to Increased Sperm Motility and Antioxidant Levels in Infertile Men

Regular Coffee Intake is Related to Increased Sperm Motility and Antioxidant Levels in Infertile Men

A Prospective Study of Coffee Drinking and Suicide in Women

Among the many reported central nervous system effects of long-term caffeine use is improvement in mood. To examine prospectively the relationship of coffee and caffeine intake to risk of death from suicide. We conducted a 10-year follow-up study (1980 to 1990) in an ongoing cohort of 86 626 US female registered nurses aged 34 to 59 years in 1980, who were free of diagnosed coronary heart disease, stroke, or cancer. Information on coffee and caffeine intake was collected by a semiquantitative food frequency questionnaire in 1980. Deaths from suicide were determined by physician review of death certificates. Fifty-six cases of suicide occurred during 832 704 person-years of observation. Compared with non-drinkers of coffee, the age-adjusted relative risk of suicide in women who consumed two to three cups per day was 0.34 (95% confidence interval [CI, 0.17 to 0.68) and 0.42 (95% CI, 0.21 to 0.86) in women who consumed four or more cups per day (P for linear trend=.002). These findings remained essentially unchanged after adjusting for a broad range of potential confounding factors, including smoking habit, alcohol intake, medication use (diazepam and phenothiazine), history of comorbid disease (hypertension, hypercholesterolemia, or diabetes), marital status, and self-reported stress. A strong inverse relationship was similarly found for caffeine intake from all sources and risk of suicide. The data suggest a strong inverse association between coffee intake and risk of suicide. Whether regular intake of coffee or caffeine has clinically significant effects on the maintenance of affect or the prevention of depression merits further investigation in clinical trials and population-based prospective studies.

Effects of moderate exercise on the pharmacokinetics of caffeine

The effect of moderate exercise on the kinetics of caffeine in 12 healthy volunteers-6 heavy coffee drinkers (HD) and 6 light coffee drinkers (LD) has been studied. Kinetics at Rest was measured first (R): the subjects remained at rest for 8 h after a single 250 mg dose of caffeine. One week later, the Exercise Kinetics (E) was measured under the same conditions, but with the subjects performing moderate exercise (30% of VO2 max) during the first hour of the study. Exercise raised the maximal plasma caffeine concentrations (R: 7.28: E: 10.45) and reduced both the half-life (R 3.99 h: E 2.29 h) and the volume of distribution (R 37 l: E 20.9 l). Both during exercise and at rest. HD had a greater half-life elimination and volume of distribution than LD. The results suggest potentiation of the effects of caffeine during exercise and an increase in its distribution due to regular heavy coffee intake.

Contribution of Environmental Factors to Variability in Human Drug Metabolism

Drug metabolism in 96 London factory and office workers has been studied after simultaneous single doses of antipyrine (phenazone) and paracetamol (acetaminophen). Metabolic clearance of both drugs was significantly greater in subjects eating meat more than once a week than in those who ate meat less frequently. The precise contribution of diet could not be clearly defined since 90% of "meat-eaters" were European while all except one of the "vegetarians" were Asian. Clearance of both drugs increased with both alcohol and cigarette consumption. Regular intake of coffee and/or tea had a similar effect but, in the case of paracetamol, this did not attain statistical significance. Antipyrine clearance was lower among women who took the oral contraceptive pill than among those who did not, while paracetamol clearance was not significantly different. These findings may have implications for the use of drugs which are administered regularly in order to achieve steady-state plasma and tissue concentrations.