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Co-occurrent use of cigarettes, alcohol, and coffee in healthy, community-living men and women.

Previous studies have examined intra-individual aggregation in the use of cigarettes, alcohol, and coffee by examining the co-occurrent use of any pair of these three substances. A recent literature review failed to find a single investigation that studied use of all three in the same sample. In the present study, co-occurrent use of all three of these substances was examined in crossvalidated subsamples of 226 male and 245 female healthy, community-living, middle-class Americans. A log-linear analysis was used to compare the proportion of smokers, ex-smokers, and nonsmokers categorized as users of more or less amounts of coffee and alcohol. Although most of the intercorrelations were not strong, the results indicate that for both sexes, smokers and ex-smokers were more likely than nonsmokers to drink greater amounts of alcohol and coffee. Furthermore, for smokers, ex-smokers, and nonsmokers, a majority of individuals who reported drinking more alcohol also reported drinking more coffee. Interestingly, the coffee and alcohol consumption levels of ex-smokers resembled those of smokers more than those of nonsmokers. Also, ex-smokers reported drinking more wine and decaffeinated coffee than either smokers or nonsmokers. Finally, the number of cigarettes smoked per day (daily quantity) was positively related to total alcohol and coffee consumption in men, but not in women. Further studies are recommended to examine the role of individual differences in the development, maintenance, and modification of these three appetitive habits and their co-occurrence.

Adolescent↗

Caffeine self-administration in humans: 2. A within-subjects comparison of coffee and cola vehicles.

The reinforcing effects of caffeine ingested in coffee versus cola were studied. Eleven participants who drank both coffee and cola (3-10 cups of coffee and 1-6 cans of cola daily; M = 632 mg caffeine/day) were tested in 4 conditions: cola at 33 mg/serving (the usual dose), coffee at 33 mg/serving, cola at 100 mg/serving, and coffee at 100 mg/serving (the usual dose). Each condition consisted of 6 double-blind weekly trials. In each trial, participants sampled caffeinated and noncaffeinated beverages and then had concurrent access to the 2 beverages. Relative use of these beverages was used to assess caffeine reinforcement. Across the 4 conditions (24 weeks), reliable caffeine reinforcement occurred in 5 participants (45%). Caffeine reinforcement did not differ as a function of vehicle or serving dose, and no vehicle-dose interactions were found. With both cola and coffee at the commonly used doses, self-reported motivation to work was greater and drowsiness and laziness smaller with caffeinated than noncaffeinated beverages. Results indicate that, among users of both coffee and cola, caffeine self-administration and subjective effects occur with both vehicles.

Adult↗

Coffee and risk of death from hepatocellular carcinoma in a large cohort study in Japan.

We examined the relation between coffee drinking and hepatocellular carcinoma (HCC) mortality in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study). In total, 110,688 cohort members (46,399 male and 64,289 female subjects) aged 40-79 years were grouped by coffee intake into three categories: one or more cups per day, less than one cup per day and non-coffee drinkers. Cox proportional hazards model by SAS was used to obtain hazard ratio of HCC mortality for each coffee consumption categories. The hazard ratios were adjusted for age, gender, educational status, history of diabetes and liver diseases, smoking habits and alcohol. The hazard ratio of death due to HCC for drinkers of one and more cups of coffee per day, compared with non-coffee drinkers, was 0.50 (95% confidence interval 0.31-0.79), and the ratio for drinkers of less than one cup per day was 0.83 (95% confidence interval 0.54-1.25). Our data confirmed an inverse association between coffee consumption and HCC mortality.

Adult↗

Folic acid supplement decreases the homocysteine increasing effect of filtered coffee. A randomised placebo-controlled study.

OBJECTIVE: Elevated levels of plasma total homocysteine (tHcy) are identified as independent risk factors for coronary heart disease and for fetal neural tube defects. tHcy levels are negatively associated with folic acid, pyridoxine and cobalamine, and positively associated with coffee consumption and smoking. A total of 600 ml of filtered coffee results in a tHcy increase that 200 mug of folic acid or 40 mg of pyridoxine supplementation might eliminate. DESIGN: Randomised, blinded study with two consecutive trial periods. SETTING: Free living population. Volunteers. SUBJECTS: A total of 121 healthy, nonsmoking men and women (78%) aged 29-65 y. INTERVENTIONS: (1) A coffee-free period of 3 weeks, (2) 600 ml coffee/day and a supplement of 200 mug folic acid/day or placebo for 4 weeks, (3) 3-week coffee-free period, (4) 600 ml coffee/day and 40 mg pyridoxine/day or placebo for 4 weeks. MAIN OUTCOME MEASURES: The difference between the change in tHcy in the supplement group and the change in tHcy in the placebo group during the 4-week trial period. RESULTS: Coffee abstention resulted in a tHcy decrease of 1.04 mumol/l for the whole group. In the subsequent coffee period, a further decrease of 0.17 mumol/l was observed in the folic acid group whereas an increase of 1.26 mumol/l was observed in the placebo group, the difference was 1.43 mumol/l (95% CI: 0.80, 2.07). Pyridoxine supplement had no impact on tHcy levels. CONCLUSIONS: Supplementation of 200 mug folic acid/day eliminates the tHcy increasing effect of 600 ml filtered coffee in subjects not already on folic acid supplements. A supplement of 40 mg pyridoxine/day does not have the same effect.

Adult↗

Microfloral contamination and hydrolytic enzyme differences between monsooned and non-monsooned coffees.

AIMS: To analyse and compare, for the first time, fungal and bacterial populations and hydrolytic enzyme production in four monsooned and non-monsooned Arabica and Robusta coffee types. METHODS AND RESULTS: Overall, using serial dilution, the populations of bacteria (approximately 10(8) cfu g(-1)) were highest in monsooned coffees of both varieties. Fungal populations were lower (10(5) cfu g(-1)) and found predominantly on monsooned coffee beans. The major fungal species were Aspergillus terreus, A. restrictus and A. ochraceus. Of 19 semi-quantitative enzymes analysed, significantly higher concentrations of 2-naphthyl-butyrate, caprylate and 2-naphthyl-D-galactopyranosidase were present in Arabica monsooned coffee. CONCLUSIONS: The results suggest that speciality monsooned coffee has markedly different microbial and physiological characteristics from normally produced green coffees. SIGNIFICANCE AND IMPACT OF THE STUDY: Monsooned coffee may have a higher contamination with spoilage moulds, especially mycotoxigenic species.

Bacteria↗

Boiled coffee fails to raise serum cholesterol in hamsters and rats.

Boiled coffee contains the lipid compounds cafestol and kahweol, which raise cholesterol strongly in man. These lipids are retained by paper filters. In a search for an animal model for the effect of coffee lipids on serum cholesterol concentrations, we fed hamsters (Mesocricetus auratus) and rats on mash diets consisting of a purified base diet and either boiled water, unfiltered boiled coffee or filtered boiled coffee. After a feeding period of 8 weeks there was no statistically significant effect of unfiltered boiled coffee on serum total cholesterol and triacylglycerol concentrations in either the hamsters or the rats. The level of serum cholesterol did respond predictably to the addition of cholesterol and/or saturated fatty acids to the diet. The lack of effect of unfiltered boiled coffee in the hamsters and the rats, when compared with the previously reported activity in humans, could not be explained by dosage, duration of treatment, mode of administration or by insufficient statistical power. It is concluded that hamsters and rats are insensitive to unfiltered boiled coffee and thus are unsuitable models for investigating its hypercholesterolaemic effect.

Animals↗

Phenolic acid metabolites as biomarkers for tea- and coffee-derived polyphenol exposure in human subjects.

Tea and coffee are rich in polyphenols with a variety of biological activities. Many of the demonstrated activities are consistent with favourable effects on the risk of chronic diseases. 4-O-methylgallic acid (4OMGA) and isoferulic acid are potential biomarkers of exposure to polyphenols derived from tea and coffee respectively. 4OMGA is derived from gallic acid in tea, and isoferulic acid is derived from chlorogenic acid in coffee. Our major objective was to explore the relationships of tea and coffee intake with 24 h urinary excretion of 4OMGA and isoferulic acid in human subjects. The relationships of long-term usual (111 participants) and contemporaneously recorded current (344 participants) tea and coffee intake with 24 h urinary excretion of 4OMGA and isoferulic acid were assessed in two populations. 4OMGA was related to usual (r 0.50, P<0.001) and current (r 0.57, P<0.001) tea intake, and isoferulic acid was related to usual (r 0.26, P=0.008) and current (r 0.18, P<0.001) coffee intake. Overall, our present results are consistent with the proposal that 4OMGA is a good biomarker for black tea-derived polyphenol exposure, but isoferulic acid may be of limited usefulness as a biomarker for coffee-derived polyphenol exposure.

Biomarkers↗

Survey of Canadian retail coffees for ochratoxin A.

One-hundred and one specimens of coffee were gathered from retail outlets across Canada and analysed for ochratoxin A. Seventy-one specimens were roasted beans or roasted ground coffee, and 30 were instant (or 'soluble') coffees. All samples were extracted with methanol-sodium bicarbonate. The extracts were cleaned up either by immunoaffinity column chromatography or by a combination of solid-phase extraction and immunoaffinity column chromatography. Ochratoxin A was quantified by liquid chromatography (LC) with fluorescence detection. The minimum quantifiable level was 0.1 ng g(-1). Ochratoxin A was present, above the minimum quantifiable level, in 42 (59%) of 71 beans and ground coffee and in 20 (67%) of 30 instant coffees. The mean ochratoxin A level in the positive samples of beans and ground coffee was 0.6 ng g(-1), and the mean level in the positive samples of instant coffee was 1.1 ng g(-1).

Canada↗

Influence of roasting and brew preparation on the ochratoxin A content in coffee infusion.

A study of the effect of coffee processing in the ochratoxin A (OTA) level has been carried out from the green beans to the drinking form. The analysis of OTA has been carried out by an in-house validated HPLC method with fluorescence detection. The limits of detection were 0.04 microg/kg for green and roasted coffee, and 0.01 microg/L for coffee brew. Thirty-six green coffee samples of different origin (Colombia, Costa Rica, Brazil, Vietnam, India and Uganda) were analysed. The highest concentrations of OTA were found in Vietnamese samples -- Robusta species treated by dry processing -- (range 0.64-8.05 microg/kg), that also showed the highest percentage of defective beans (7.6%). These contaminated samples were roasted in a process that controlled loss of weight and color, as in the industry. A mean reduction of 66.5% was obtained, but the reduction seems to be heterogeneous. Coffee brew was prepared by the three brewing processes more utilized in Europe: moka, auto-drip and espresso. A reduction of the OTA level has been attained, being greater when using a espresso coffee maker (49.8%) than when using auto-drip (14.5%) or moka brewing (32.1%). Therefore, the method of coffee brew preparation plays a key role in the final OTA human exposure.

Chromatography, High Pressure Liquid↗

Effect of the frequency of the mixing of coffee cherries put out for drying on the kinetics of drying and the relationship to ochratoxin A production.

The effect of the frequency of the mixing of coffee cherries put out for sun drying on the kinetics of the drying, fungal growth and kinetics of ochratoxin A production was evaluated. The results showed that the more coffee cherries were mixed, the quicker they dried. This rapidity of drying led to a reduction of fungal development. Indeed, coffee cherries mixed eight and ten times a day, dried quickly and were free inside of fungi. However, infection by fungi gives little indication of ochratoxin A production in coffee cherries. Indeed, although coffee cherries mixed twice a day were more contaminated by fungi, the analysis of ochratoxin A content showed they were free of this mycotoxin. The coffee cherries that were more contaminated by ochratoxin A were those mixed four times a day (containing 0.35-5.46 microg kg(-1) ochratoxin A). Ochratoxin A contamination was essentially due to the presence of Aspergillus species capable of producing ochratoxin A inside the coffee cherries.

Aspergillus↗

Survey of ochratoxin A in UK retail coffees.

A new method providing sensitivity to low concentrations was developed for the analysis of ochratoxin A in roast and ground and soluble coffee and a survey has been carried out to determine levels of ochratoxin A (OTA) in 100 samples of retail coffees available in the UK. The survey covered 80 soluble coffees (granulated, powdered, freeze-dried), of which nine products were decaffeinated, and 20 roast and ground retail coffee samples. OTA was detected (> or = 0.1 microgram/kg) in 64 samples of soluble coffee at levels ranging from 0.1 to 8 micrograms/kg. Seventeen samples of roast and ground coffee contained OTA at levels between 0.2 and 2.1 micrograms/kg. These results indicate that coffee products are not a major dietary source of OTA in the UK.

Carcinogens↗

Coffee consumption and markers of inflammation and endothelial dysfunction in healthy and diabetic women.

BACKGROUND: In several short-term studies, coffee consumption has been associated with impairment of endothelial function. OBJECTIVE: The objective was to assess the relation between long-term caffeinated and decaffeinated filtered coffee consumption and markers of inflammation and endothelial dysfunction. DESIGN: We conducted a cross-sectional study of 730 healthy women and 663 women with type 2 diabetes from the Nurses' Health Study I cohort, who were aged 43-70 y and free of cardiovascular disease and cancer at the time blood was drawn (1989-1990). Dietary intake was assessed with a validated food-frequency questionnaire in 1986 and 1990. RESULTS: About 77% of the healthy women consumed > or =1 cup (237 mL) caffeinated coffee/mo and 75% consumed > or =1 cup decaffeinated coffee/mo; the corresponding intakes for women with type 2 diabetes were 74% and 63%, respectively. In healthy women, no appreciable differences in plasma concentrations of the markers were found across categories of caffeinated coffee intake. In women with type 2 diabetes, higher caffeinated coffee consumption was associated with lower plasma concentrations of E-selectin (adjusted percentage change per 1 cup/d increment = -3.2%; P = 0.05) and C-reactive protein (adjusted percentage change = -10.2%; P < 0.001). Higher decaffeinated coffee consumption was associated with lower plasma concentrations of E-selectin (adjusted percentage change = -2.5%; P = 0.08) and C-reactive protein (adjusted percentage change = -7.9%; P = 0.02) only in healthy women. The results were similar when we also adjusted the models for other dietary factors and blood lipids and when we excluded participants with hypertension or hypercholesterolemia. CONCLUSIONS: These results indicate that neither caffeinated nor decaffeinated filtered coffee has a detrimental effect on endothelial function. In contrast, the results suggest that coffee consumption is inversely associated with markers of inflammation and endothelial dysfunction.

Adult↗

Coffee consumption and cognitive function among older adults.

This study examined the association of caffeinated and decaffeinated coffee intake with cognitive function in a community-based sample of older adults in 1988-1992. Participants were 890 women with a mean age of 72.6 years and 638 men with a mean age of 73.3 years from the Rancho Bernardo Study. Cognitive function was assessed by 12 standardized tests, and lifetime consumption and current coffee consumption were obtained by questionnaire. After adjustment for confounders, higher lifetime coffee consumption in women was associated with better (p < or = 0.05) performance on six of 12 tests, with a trend (p < or = 0.10) on two other cognitive function tests; current caffeinated coffee intake was associated with better performance on two tests (p < 0.05), with a trend (p < 0.10) on one other test. Among women aged 80 or more years, lifetime coffee intake was nonsignificantly associated with better performance on 11 of the 12 tests. No relation was found between coffee intake and cognitive function among men or between decaffeinated coffee intake and cognitive function in either sex. Lifetime and current exposure to caffeine may be associated with better cognitive performance among women, especially among those aged 80 or more years.

Adult↗

Consumption of boiled coffee is correlated with serum cholesterol in Finland.

The association between coffee consumption and serum cholesterol concentration was studied in a cross-sectional epidemiological study among 5704 men and women in Finland. The mean serum cholesterol values of those consuming boiled coffee (24% of the subjects) was significantly higher than that of drinkers of filtered coffee (69% of the subjects) in both sexes after adjusting for age, body mass index, smoking, serum gamma-glutamyltransferase, index of saturated fat intake, and physical activity: in men 6.37 versus 6.02 mmol/l, in women 6.22 versus 5.84 mmol/l, both significant at p less than 0.001. A significant dose-dependent effect was observed between the consumption of boiled coffee both in men and in women. For filter coffee drinkers a weak coffee dose-cholesterol association was found only for women. The magnitude of the effect of boiled coffee, 0.3-0.4 mmol/l in serum cholesterol values, is in accordance with the results from controlled trials carried out among both hyper- and normocholesterolaemic subjects.

Adult↗

Italian style brewed coffee: effect on serum cholesterol in young men.

BACKGROUND: Increases in blood lipids have been observed in humans when coffee is brewed by the boiling method. The purpose of this study was to evaluate if giving up Italian coffee might reduce blood cholesterol levels. METHODS: Eighty-four normolipidaemic young adult males, after a 3-week baseline (BL), were randomly assigned to three different regimens of coffee consumption: espresso (E), mocha (M), and no coffee, but tea (T). The average coffee consumption during intervention (I) was 3.1 +/- 1.2 and 2.8 +/- 1.1 cups per day for espresso and mocha group respectively (espresso: 25-35 ml/cup; mocha: 40-50 ml/cup). Total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides were measured eight times during the study. Dietary pattern, alcohol consumption, smoking habits, drug use, and anthropometric data were also recorded. RESULTS: The changes observed in serum cholesterol concentration between baseline and intervention were not statistically different in all groups. The changes were 0.0 mmol/l (T), +0.01 mmol/l (E) and +0.05 mmol/l (M) for total serum cholesterol; 0 mmol/l (T), -0.02 mmol/l (E) and -0. 03 mmol/l (M) for HDL-C; -0.13 mmol/l (T), +0.02 mmol/l (E) and -0. 05 mmol/l (M) for LDL-C. Serum triglycerides showed a significant increase during intervention (P < 0.01 by ANOVA) in all groups with a change of 0.18 mmol/l, 0.18 mmol/l and 0.22 mmol/l, for tea, espresso and mocha group respectively. CONCLUSIONS: The results indicate that coffee brewed in the Italian way does not alter blood levels of total cholesterol, HDL-cholesterol and LDL-cholesterol, since no significant differences were observed in these blood parameters after a 6-week break from coffee consumption.

Adult↗

A randomized intervention study of the effects of discontinuing coffee intake on growth and morbidity of iron-deficient Guatemalan toddlers.

Coffee is widely consumed by children in Guatemala. To evaluate whether coffee has an adverse effect on growth or morbidity, 160 children 12-24 mo of age who had received coffee for > or = 2 mo and had at least one indicator of iron deficiency were stratified by initial hemoglobin (Hb) (A = anemic vs. NA = "nonanemic", i.e., Hb > or = 105 g/L) and randomly assigned to a control (C = continuation of coffee) or intervention group (S = provided with a substitute consisting of sugar and coloring) for 5 mo. Anemic children were provided iron supplements for 2-3 mo. Hematological and anthropometric measurements were made before and after the intervention, and dietary and morbidity data were collected every 2 wk. A total of 139 children completed the intervention: 45 C-NA, 56 S-NA, 19 C-A and 19 S-A. Compliance with the intervention was good: median coffee intake was 127 mL/d in group C vs. 3 mL/d in group S (P = 0.0001). There were no significant differences between C vs. S groups in food intake before or after the intervention. In the total sample, there was no effect of the intervention on weight or length gain. However, in children initially consuming more than 100 mL/d of coffee (n = 96), length gain was 22% greater in the S vs. the C group (P = 0.07), and weight gain was 46% greater in the S-A vs. the C-A group (P < 0.05; NS in the NA groups). Total illness prevalence (particularly respiratory illness) was significantly lower in the S-NA vs. the C-NA group (P < 0.05), but somewhat higher in the S-A vs. the C-A group (P = 0.09). Morbidity differences did not explain the effect of the intervention on growth. These results indicate a modest increase in growth associated with discontinuation of coffee consumption by toddlers with initial intakes >100 mL/d.

Anemia, Iron-Deficiency↗

Breast cancer and the consumption of coffee.

The hypothesis has been raised that coffee consumption may increase the incidence of breast cancer, based on the report that fibrocystic breast disease, a risk factor for breast cancer, regresses after abstention from coffee and other methylxanthines. The relation between recent coffee consumption and the risk of breast cancer was evaluated in a case-control study, based on interviews conducted 1975-1982 at several mainly eastern US teaching and community hospitals. The responses of 2,651 women with newly diagnosed breast cancer were compared with those of 1,501 controls with nonmalignant conditions and 385 controls with cancers at other sites. The relative risk estimates for levels of coffee drinking up to seven or more cups daily, relative to none, approximated 1.0 with narrow 95% confidence intervals. After allowance for confounding, the relative risk estimate for drinking at least five cups a day was 1.2 (95% confidence interval, 0.9-1.6) using the noncancer controls and 1.1 (0.7-1.6) using the cancer controls. Coffee consumption was not associated with an increase in the risk of breast cancer among women with a history of fibrocystic breast disease, nor were tea or decaffeinated coffee associated with an increase in the risk of breast cancer. The results suggest that the recent consumption of coffee does not influence the incidence of breast cancer.

Adult↗

Coffee drinking and nonfatal myocardial infarction in men under 55 years of age.

The relation of coffee consumption to the risk of nonfatal first myocardial infarction in men under 55 years of age was assessed in a hospital-based case-control study conducted from 1980 to 1983 in hospitals in Massachusetts, Rhode Island, Connecticut, and New York: 1,873 men with first nonfatal myocardial infarctions were compared with 1,161 controls admitted for conditions unrelated to coffee ingestion. After allowance for major risk factors for myocardial infarction, the relative risk estimate for recent consumption of caffeine-containing coffee increased with increasing level of daily intake, from 1.4 for one to two cups per day to 1.6 for three to four cups, 1.8 for five to nine cups, and 2.9 for greater than or equal to 10 cups, relative to consumption of no coffee (p less than 0.001 for trend). The association was apparent in each age group and in both smokers and nonsmokers. For those who drank decaffeinated coffee only, on the basis of small numbers, there was a suggestion of an increased risk among men who had consumed at least five cups daily for less than five years but not among those who had drunk this amount for at least five years; whether the apparent association among the shorter-term drinkers was due to previous consumption of caffeine-containing coffee could not be determined. The findings suggest that caffeine-containing coffee increases the risk of myocardial infarction and that men who drink at least five cups daily may increase their risk by about twofold or more.

Adult↗