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PubMed1983

The prevalence of coffee drinking among hospitalized and population-based control groups.

Data on coffee-drinking habits obtained from a case-control study conducted in Detroit were used to compare the proportions of coffee drinkers in a hospital and a population control series. The comparison was based on interviews with 262 hospitalized controls and 427 population controls. The overall proportion of coffee drinkers in the total hospital control group was similar to that in the population control group. However, the proportion of moderate-to-heavy coffee drinkers among controls hospitalized for conditions that may have caused them to alter their diet (eg, gastrointestinal disorders and cardiovascular disease) was lower than that among population controls. In contrast, the proportion of moderate-to-heavy coffee drinkers among controls hospitalized for conditions that probably did not cause a change in diet (eg, fractures) was almost identical to that among population controls. These results suggest that, in hospital-based case-control studies of the effects of coffee consumption, it would be prudent to restrict the referent group to those patients hospitalized for conditions that probably did not cause a change in diet. The magnitude of bias resulting from failure to exclude controls hospitalized for diet-altering conditions will depend on two factors that may vary between studies: (1) the distribution of diet-altering conditions among the hospital controls, and (2) the relationship of these diseases to coffee consumption.

Adult↗
PubMed1994

Effects of two kinds of decaffeinated coffee on serum lipid profiles in healthy young adults.

OBJECTIVE: To investigate the effects of two kinds of decaffeinated coffee on serum lipid profiles in healthy young adults. DESIGN: Randomized controlled study with three study groups and a parallel design, consisting of two consecutive periods. SETTING: Outpatient clinical research center in a university clinic. SUBJECTS: 119 healthy students (60 male, 59 female) who were selected after a screening. All completed the study. Blood samples of three subjects (1 male, 2 female) were excluded from evaluation due to later diagnosed genetic anomalies of lipid metabolism. INTERVENTIONS: All subjects consumed 750-1000 ml of caffeinated filtered coffee per day for a 2 week wash-in period. During the 6 week test period one group continued drinking the caffeinated coffee, while the two other groups consumed different kinds of decaffeinated coffee. RESULTS: Consumption of both types of decaffeinated coffee did not lead to any significant changes in serum total and LDL cholesterol, triglycerides and apolipoprotein B. Furthermore, there were no significant differences in the reactions between the three groups. The diet did not change during the study. CONCLUSIONS: Switch from regular to decaffeinated coffee had no cholesterol-elevating effects, irrespective of the type of coffee.

Adult↗
PubMed1998

Coffee consumption and the risk of breast cancer.

On the basis of clinical observations that some women with fibrocystic breast disease experienced resolution of the disease on eliminating methylxanthines from their diet, it has been suggested that coffee intake might be related to breast carcinogenesis. The relationship between coffee (mostly expresso and mocha), decaffeinated coffee and tea intake and breast cancer risk was therefore considered, combining data from two case-control studies, conducted in Italy between 1983 and 1994. Cases were 5,984 women, below age 75, with histologically confirmed breast cancer, and controls were 5,504 women admitted to hospital for a wide spectrum of acute, non-neoplastic, non-hormone-related diseases. The odds ratios (ORs) were estimated from multiple logistic regression equations including terms for study/centre, age, education, body mass index, smoking status, total alcohol intake, age at menarche and menopause, parity and age at first birth, use of oral contraceptives, use of hormone replacement therapy, history of benign breast disease and family history of breast cancer. No relationship was observed between coffee intake and the risk of breast cancer. The multivariate ORs were 1.17 (1.03-1.33), 1.17 (1.04-1.33), 1.21 (1.06-1.37) and 0.96 (0.83-1.11) for women drinking < 2, 2, > 2 to < 4 and > or = 4 cups/day compared to non-drinkers. Decaffeinated coffee was consumed only by 6-7% of cases and controls and the corresponding OR was 0.84 (0.72-0.98). Tea consumption was also low and not associated with the risk of breast cancer (OR 0.94, 95% CI 0.85-1.03). No significant heterogeneity was found for coffee intake across strata of age at diagnosis, education, body mass index, smoking status, total alcohol intake, age at menarche and menopause, parity, age at first birth, ever use of oral contraceptives, hormone replacement therapy, history of benign breast disease and family history of breast cancer. Thus, this study, based on a large data set, allows us to exclude the hypothesis that coffee intake is related to breast cancer risk in this Italian population.

Adult↗
PubMed2005

Effect of coffee intake on blood flow and maternal stress during the third trimester of pregnancy.

OBJECTIVE: To investigate the effects of maternal ingestion of an ordinary dose of coffee on maternal stress and placental and fetal blood circulation during the third trimester of pregnancy. METHODS: We performed a Doppler blood flow analysis for 10 women in the third trimester of pregnancy before and after they drank a cup of coffee. Salivary samples were collected from the 10 pregnant women and 14 nonpregnant controls just before coffee intake and 30 min later. Salivary cortisol levels and chromogranin A titers were determined. RESULTS: Coffee intake had no effect on maternal or fetal blood flow. Among the pregnant women, Salivary cortisol levels were significantly reduced after coffee intake but salivary chromogranin A concentration was not significantly different before and after coffee intake. CONCLUSION: The reduced salivary cortisol levels suggest that coffee intake decreases maternal stress during pregnancy.

Arteries↗
PubMed2002

The effects of coffee consumption on sleep and melatonin secretion.

BACKGROUND: In this study we examined the effects of caffeine on sleep quality and melatonin secretion. Melatonin is the principal hormone responsible for synchronization of sleep. Melatonin secretion is controlled by neurotransmitters that can be affected by caffeine. METHODS: In the first part of the study, six volunteers drank either decaffeinated or regular coffee in a double-blind fashion on one day, and the alternate beverage 7 days later. Sleep parameters were assessed by actigraphy. In the second part of the study, the subjects again drank either decaffeinated or regular coffee, and they then collected urine every 3h for quantitation of 6-sulphoxymelatonin (6-SMT), the main metabolite of melatonin in the urine. RESULTS: We found that drinking regular caffeinated coffee, compared to decaffeinated coffee, caused a decrease in the total amount of sleep and quality of sleep, and an increase in the length of time of sleep induction. Caffeinated coffee caused a decrease in 6-SMT excretion throughout the following night. CONCLUSIONS: The results of our study confirm the widely held belief that coffee consumption interferes with sleep quantity and quality. In addition, we found that the consumption of caffeine decreases 6-SMT excretion. Individuals who suffer from sleep abnormalities should avoid caffeinated coffee during the evening hours.

Journal Article↗
PubMed2005

Antioxidant properties of roasted coffee residues.

The antioxidant activity of roasted coffee residues was evaluated. Extraction with four solvents (water, methanol, ethanol, and n-hexane) showed that water extracts of roasted coffee residues (WERCR) produced higher yields and gave better protection for lipid peroxidation. WERCR showed a remarkable protective effect on oxidative damage of protein. In addition, WERCR showed scavenging of free radicals as well as the reducing ability and to bind ferrous ions, indicating that WERCR acts as both primary and secondary antioxidants. The HPLC analyses showed that phenolic acids (chlorogenic acid and caffeic acid) and nonphenolic compounds [caffeine, trigonelline, nicotinic acid, and 5-(hydroxymethyl)furfuraldehyde] remained in roasted coffee residues. These compounds showed a protective effect on a liposome model system. The concentrations of flavonoids and polyphenolic compounds in roasted coffee residues were 8,400 and 20,400 ppm, respectively. In addition, the Maillard reaction products (MRPs) remaining in roasted coffee residues were believed to show antioxidant activity. These data indicate that roasted coffee residues have excellent potential for use as a natural antioxidant source because the antioxidant compounds remained in roasted coffee residues.

Antioxidants↗
PubMed2005

Effect of roasting on the formation of chlorogenic acid lactones in coffee.

Of all plant constituents, coffee has one of the highest concentrations of chlorogenic acids. When roasting coffee, some of these are transformed into chlorogenic acid lactones (CGL). We have studied the formation of CGL during the roasting of coffee beans in Coffea arabica cv. Bourbon; C. arabicacv. Longberry; and C. canephora cv. Robusta. Individual CGL levels were determined by comparison of HPLC peaks with those of synthetic CGL standards. Seven CGL were identified: 3-caffeoylquinic-1,5-lactone (3-CQL), 4- caffeoylquinic-1,5-lactone (4-CQL), 3-coumaroylquinic-1,5-lactone (3-pCoQL), 4-coumaroylquinic-1,5-lactone (4-pCoQL), 3-feruloylquinic-1,5-lactone (3-FQL), 4-feruloylquinic-1,5-lactone (4-FQL), and 3,4-dicaffeoylquinic-1,5-lactone (3,4-diCQL). 3-CQL was the most abundant lactone in C. arabica and C. canephora, reaching peak values of 230 +/- 9 and 254 +/- 4 mg/100 g (dry weight), respectively, at light medium roast ( approximately 14% weight loss). 4-CQL was the second most abundant lactone (116 +/- 3 and 139 +/- 2 mg/100 g, respectively. The maximum amount of CGL represents approximately 30% of the available precursors. The relative levels of 3-CQL and 4-CQL in roasted coffee were reverse to those of their precursors in green coffee. This suggests that roasting causes isomerization of chlorogenic acids prior to the formation of lactones and that the levels of lactones in roasted coffee do not reflect the levels of precursors in green coffee.

Chlorogenic Acid↗
PubMed2005

DNA extraction and analysis from processed coffee beans.

The authenticity of coffee is an important issue for both producers and consumers. Premium Arabica material is especially prone to being adulterated, and a number of different techniques have been employed to determine the quality of both roasted and instant coffee. Currently, assessment of coffee authenticity relies on chemical methods which can discriminate between coffee species, but not varieties. Several genetic markers are available for assessing coffee origin, but their suitability to testing commercial coffee is limited by the ability to extract DNA from highly processed beans. In this paper, we demonstrate that PCR-grade DNA may be obtained from roasted beans and even instant coffee. This would allow analysis of commercial samples, provided that suitable markers for species/variety identification are found.

Coffea↗
PubMed1985

Coffee consumption, diet, and lipids.

Recent reports suggest that coffee consumption is associated with increased serum cholesterol and triglyceride concentrations. The authors examined the association between serum lipids and coffee consumption and other caffeinated beverages as part of a population-based study of 1,228 women and 923 men, aged 25-64 years, in San Antonio, Texas, studied between October 1979 and November 1982. The study confirmed a positive relationship between coffee consumption and both total and low density lipoprotein cholesterol in both sexes which persisted after adjustment for age, ethnicity, obesity, cigarette smoking, and alcohol consumption. Neither tea nor cola consumption was associated with changes in serum lipids, suggesting that caffeine alone does not exert a direct effect on lipid levels. The possibility was examined that the coffee-cholesterol relationship might be due to a more atherogenic diet consumed by heavy coffee drinkers. In men, per cent calories from both total and saturated fat and dietary cholesterol intake increased with increased coffee consumption. Similar trends were not observed in women, however. The positive relationship between coffee and cholesterol may therefore be due to confounding effects of other aspects of the diet.

Adult↗
PubMed2005

[Knowledge and attitude of workers and patrons in coffee houses, cafes, restaurants about cigarette smoke].

A legislation about smoking restriction in all workplaces is under consideration in Turkey. In our study we evaluated the knowledge and attitudes of workers and patrons of cafes, restaurants and coffee houses about smoking ban in their work places. Twenty eight owners, 67 workers and 242 patrons in 12 coffee house, 12 restaurants and 7 cafes were interviewed. A desire to work in a smoke-free workplace was most frequent (79.8%) among coffee house group and 63.9% in cafe group, 57.8% in restaurants group. Smoking ban was most frequently requested by coffee house group and least frequently by cafe group. Coffee house and cafe groups were supposing a decrease in the number of patrons and incomes with such a legislation, whereas restaurant group was thinking that no change will occur. 45.4% of the coffee house patrons stated that they would less frequently visit that workplace in case of a smoking ban, whereas 47.8% of restaurant patrons stated that there would be no change with their frequency to visit there. A desire to work in a smoke-free workplace and requesting a smoking ban for all workplaces were more frequent among nonsmokers. Smokers stated that their frequency to visit those places would decrease in case of a smoking ban, whereas nonsmokers stated an increase in their frequency to visit those places. We think that informing the owners and workers of coffee houses, restaurants and cafes about these facts is very important and would increase the compliance to such a legislation.

Health Knowledge, Attitudes, Practice↗
PubMed2006

Coffee, cirrhosis, and transaminase enzymes.

BACKGROUND: A minority of persons at risk develop liver cirrhosis, but knowledge of risk modulators is sparse. Several reports suggest that coffee drinking is associated with lower cirrhosis risk. METHODS: We studied 125,580 multiethnic members of a comprehensive prepaid health care plan without known liver disease who supplied baseline data at voluntary health examinations from 1978 to 1985. Subsequently, through 2001, 330 of them were diagnosed with liver cirrhosis. Review of medical records confirmed the diagnosis of cirrhosis and ascertained probable etiology. The association of coffee drinking with cirrhosis was estimated by Cox proportional hazards models with 7 covariates. We also did a cross-sectional analysis of baseline aspartate aminotransferase and alanine aminotransferase levels, studied by logistic regression. RESULTS: In the cohort study, relative risks of alcoholic cirrhosis (199 subjects) for coffee drinking (vs none) were less than 1 cup per day, 0.7 (95% confidence interval [CI], 0.4-1.1); 1 to 3 cups, 0.6 (95% CI, 0.4-0.8; P<.001); and 4 or more cups, 0.2 (95% CI, 0.1-0.4; P<.001). For 131 subjects with nonalcoholic cirrhosis, relative risks were less than 1 cup, 1.2 (95% CI, 0.6-2.2); 1 to 3 cups, 1.3 (95% CI, 0.8-2.1); and 4 or more cups, 0.7 (95% CI, 0.4-1.3). These relative risks for coffee drinking were consistent in subsets. Tea drinking was unrelated to alcoholic or nonalcoholic cirrhosis. In the cross-sectional analyses, coffee drinking was related to lower prevalence of high aspartate aminotransferase and alanine aminotransferase levels; for example, the odds ratio of 4 or more cups per day (vs none) for a high aspartate aminotransferase level was 0.5 (95% CI, 0.4-0.6; P<.001) and for a high alanine aminotransferase level, 0.6 (95% CI, 0.6-0.7; P<.001), with stronger inverse relations in those who drink large quantities of alcohol. CONCLUSION: These data support the hypothesis that there is an ingredient in coffee that protects against cirrhosis, especially alcoholic cirrhosis.

Alanine Transaminase↗
PubMed2002

Coffee, tea, and caffeine consumption and risk of rheumatoid arthritis: results from the Iowa Women's Health Study.

OBJECTIVE: To evaluate whether coffee, tea, and caffeine consumption are risk factors for rheumatoid arthritis (RA) onset among older women. METHODS: These factors were evaluated in a prospective cohort study that was initiated in 1986 and that included 31,336 women ages 55-69 years without a history of RA. Risk factor data were self-reported using a mailed questionnaire. Through 1997, 158 cases of RA were identified and validated against medical records. The relative risk (RR) and 95% confidence interval (95% CI) were used as the measures of association and were adjusted for age, alcohol use, smoking history, age at menopause, marital status, and the use of hormone replacement therapy. RESULTS: Compared with those reporting no use, subjects drinking > or =4 cups/day of decaffeinated coffee were at increased risk of RA (RR 2.58, 95% CI 1.63-4.06). In contrast, women consuming >3 cups/day of tea displayed a decreased risk of RA (RR 0.39, 95% CI 0.16-0.97) compared with women who never drank tea. Caffeinated coffee and daily caffeine intake were not associated with the development of RA. Multivariable adjustment for a number of potential confounders did not alter these results. The associations of RA onset with the highest categories of decaffeinated coffee consumption (RR 3.10, 95% CI 1.75-5.48) and tea consumption (RR 0.24, 95% CI 0.06-0.98) were stronger in women with seropositive disease compared with those with seronegative disease (RR 1.54, 95% CI 0.62-3.84 and RR 0.93, 95% CI 0.27-3.20, respectively). CONCLUSION: Decaffeinated coffee intake is independently and positively associated with RA onset, while tea consumption shows an inverse association with disease onset. Further investigations of decaffeinated coffee and tea intake as arthritis risk factors are needed to verify these findings and explore their biologic basis.

Aged↗
PubMed2006

Exploring an interaction of adenosine A2A receptor variability with coffee and tea intake in Parkinson's disease.

Caffeine is an adenosine receptor A1 and A2A receptor antagonist and a putative functional genetic variant of the A2A receptor (2592C > Tins) mediates caffeine-induced anxiety. Here we investigated the potential interaction of this A2A genetic variant with the quantity of coffee and tea intake and their relationship with the risk of PD. A total of 441 subjects consisting of 222 PD and 219 race, gender and age matched controls were included. A multivariate analysis of the variables including the 2592C > Tins A2A genotypes, age of onset, gender, and the quantity of tea and coffee intake, interaction of the A2A genotypes with coffee intake, interaction of A2A genotypes with tea intake demonstrated the quantity of coffee intake to be significantly associated with PD (P < 0.0005, OR = 0.922, 95% CI: 0.881, 0.964). However, there was no significant interaction of the A2A genotypes with the quantity of coffee and tea intake in modulating the risk of PD. The dose dependent protective effect of coffee intake in PD was independent of the 2592C > Tins A2A genotype suggesting that the pharmacogenetic action of caffeine in PD may be mediated differently from other caffeine-induced neurologic syndromes.

Base Sequence↗
PubMed2006

Coffee consumption and breast cancer risk among BRCA1 and BRCA2 mutation carriers.

Although there are several plausible biologic mechanisms whereby coffee consumption might influence the risk of breast cancer, epidemiologic evidence is limited. We assessed the association between coffee consumption and breast cancer risk among high-risk women who carry BRCA mutations. We performed a matched case-control analysis on 1,690 women with a BRCA1 or BRCA2 mutation from 40 centers in 4 countries. Average lifetime coffee consumption was estimated via a self-administered questionnaire. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. After adjustment for potential confounders, the ORs for breast cancer in BRCA carriers who habitually drank 0, 1-3, 4-5 and 6 or more cups of coffee were 1.00, 0.90 (95% CI 0.72-1.12), 0.75 (95% CI 0.47-1.19) and 0.31 (95% CI 0.13-0.71; p-trend = 0.02). The effect was limited to the consumption of caffeinated coffee. These results suggest that among women with BRCA gene mutation, coffee consumption is unlikely to be harmful and that high levels of consumption may in fact be related to reduced breast cancer risk.

Adult↗
PubMed1991

Coffee contains cholinomimetic compound distinct from caffeine. I: Purification and chromatographic analysis.

Both regular and decaffeinated coffees were found to have cholinomimetic actions when tested in urethane-anesthetized rats. These actions were distinct from those of caffeine and reversible by atropine. The bioactive fraction was purified from alcoholic extracts of instant decaffeinated coffee by liquid column chromatography and preparative TLC. The purified compound showed similar pharmacological actions as the starting material. Chromatographic behavior was further characterized by analytical TLC and HPLC. Chromatographic analyses of extracts of green coffee beans and roasted ground coffees showed that the cardioactive compound was only present in roasted coffees. Similar analyses of other commonly consumed beverages, including teas and cocoa, showed that this compound was not present in beverages besides coffee.

Acetylcholine↗
PubMed1992

Cholinomimetic compound distinct from caffeine contained in coffee. II: Muscarinic actions.

An extract with cholinergic activities was isolated from instant regular and decaffeinated coffees and purified. Intravenous injection of this cholinomimetic extract of coffee produced an abrupt depression in blood pressure and heart rate, changes that were distinct from those of known components of coffee, including caffeine, trigonelline, catechin, and chlorogenic acid. Pretreatment of the animals with naloxone, propranolol, isobutylmethylxanthine, hexamethonium bromide, and hemicholinium-3 chloride or bilateral vagotomy did not affect the cardiodepressive effects of the extract, whereas atropine completely abolished them. Direct injection of the cholinomimetic extract of coffee (20-100 micrograms) into the periaqueductal gray area of the midbrain did not produce any cardiovascular effect. However, the extract of coffee did cause relaxation of isolated rat and rabbit aortic ring preparations that were contracted under norepinephrine. The cholinomimetic extract did not inhibit purified acetylcholinesterase. This pharmacologic profile indicates that the cholinomimetic extract of coffee acts as a direct muscarinic agonist.

Animals↗
PubMed2006

Studies on acrylamide levels in roasting, storage and brewing of coffee.

The content of acrylamide in coffee reaches a peak early in the roasting process, reflecting occurrence of both formation and destruction of acrylamide during roasting. Levels of acrylamide in the fully roasted product are a small fraction of the peak reached earlier. Glucose and moisture in green coffee do not show a significant correlation with acrylamide in roasted coffee. Pre-roasting levels of asparagine show a correlation only in Arabica coffee. The main factors affecting the level of acrylamide in roasted coffee appear to be the Arabica/Robusta ratio, with Robusta giving higher levels; time and degree of roast, with both shorter and lighter roasting at the edges of the normal roasting range giving higher levels; storage condition and time, with clear reduction at ambient storage. This storage reduction of acrylamide followed second order reaction kinetics with an activation energy of 73 KJ/mole. The acrylamide in roasted coffee is largely extracted into the brew and stable within usual time of consumption. As these four main factors also substantially affect the sensorial characteristics of the brew, and as modifications of the process have to comply with the consumer-accepted boundaries of taste profiles, only small effects on the acrylamide level are expected to be achievable.

Acrylamide↗
PubMed1993

Coffee consumption and serum cholesterol. GISSI-EFRIM Study Group.

The relationship between coffee consumption and serum cholesterol was examined in the comparison group of a case-control study of myocardial infarction involving 642 patients from various Italian regions who were hospitalized for diseases having no relationship to cardiovascular disease risk factors. Overall mean total cholesterol was 198.9 mg/dl. Mean cholesterol values (in mg/dl) standardized for age, sex, and smoking habits were 204.0 for nonconsumers of coffee, 194.8 for drinkers of one cup per day, 196.5 for two, 202.9 for three, 205.9 for four, and 206.5 for five or more cups per day. Thus, serum cholesterol levels were higher in non-coffee drinkers than in moderate drinkers; among coffee drinkers, however, there was a direct, although moderate, relationship between the amount of coffee consumed and the total cholesterol levels. A similar though less consistent pattern was also evident across separate strata of sex, age, and smoking habits, and the association was appreciably greater among younger subjects (below age 50). Although mean cholesterol levels in this Italian dataset were lower than those in other populations from northern Europe and the United States, the relative difference between moderate and heavy drinkers was proportionally similar to that reported in other studies. These results are of special interest since most Italian coffee (i.e., mocha or espresso) is unfiltered.

Adult↗