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Effect of coffee and cigarette smoking on the blood pressure of patients with accelerated (malignant) hypertension.

There is a strong association between cigarette smoking and accelerated hypertension. In mild hypertension smoking cigarettes has a distinct pressor effect and caffeine a small but more prolonged pressor action. Coffee and cigarette smoking together have an additive effect on blood pressure (BP). We have examined the interaction of cigarette smoking and drinking coffee on the BP of six patients who presented with accelerated hypertension (mean BP 240/140 mm Hg) and were heavy smokers and caffeine users. After initial control of the BP, the effects of smoking alone, coffee plus smoking, and placebo were examined in a balanced cross-over study. Baseline BP averaged 154/91 mm Hg and remained stable for 90 min after abstention from smoking and caffeine (placebo). Cigarette smoking without caffeine caused a modest rise in BP (mean 9/8 mm Hg), but the combination of coffee plus cigarette smoking caused a progressive increase in BP to an average 21/17 mm Hg (P < 0.05/P < 0.002) higher than placebo values. The effect of coffee was significantly additive to that of smoking alone. Smoking plus coffee ingestion shifted the BP from acceptable (155/94 mm Hg) to poor control (175/107 mm Hg). This pressor effect was observed despite treatment, and with amounts of caffeine and cigarettes which were in no way unusual for these patients. We propose that the association of cigarette smoking with accelerated hypertension may reflect an extreme pressor effect of combined smoking and caffeine use in some patients.

Adult↗

Caffeine and coffee: effects on health and cardiovascular disease.

Caffeine is a methylxanthine whose primary biological effect is the competitive antagonism of the adenosine receptor. Its presence in coffee, tea, soda beverages, chocolate and many prescription and over-the-counter drugs makes it a commonly consumed stimulant. Coffee and/or caffeine consumption has been linked to many human diseases in epidemiologic studies. Causal relationships have been difficult to substantiate. Initial investigations, showing an association between coffee and coronary heart disease, suffer from confounding variables and have been difficult to replicate. Recent studies, showing a significant effect over long follow-up periods and with high coffee intake, have again raised the question of a role for coffee and/or caffeine consumption in the pathogenesis of atherosclerotic heart disease. Contrary to common belief, the published literature provides little evidence that coffee and/or caffeine in typical dosages increases the risk of infarction, sudden death or arrhythmia.

Caffeine↗

Coffee consumption and risk of acute myocardial infarction in Italian males. GISSI-EFRIM. Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto, Epidemiologia dei Fattori di Rischio del'Infarto Miocardico.

The relationship between coffee consumption and acute myocardial infarction (AMI) was analyzed using data from a case-control study conducted in 1988 to 1989 within the framework of the GISSI-2 trial on streptokinase versus alteplase and heparin versus no heparin in the treatment of AMI. A total of 801 male patients with AMI and 792 control subjects who were hospitalized in several Italian regions for diseases unrelated to known or potential risk factors for cardiovascular diseases were included. Compared with coffee nondrinkers, the multivariate relative risks (RRs), after allowance for age, education, body mass index, smoking habits, alcohol consumption, family history of AMI, cholesterol level, history of diabetes, and hypertension, were 0.8 (95% confidence interval (CI), 0.5 to 1.2) for consumption of one cup/d, 1.3 (95% CI, 0.9 to 2.0) for two cups/d, 1.8 (95% CI, 1.1 to 2.7) for three cups, 2.5 (95% CI, 1.5 to 4.1) for four cups, and 2.6 (95% CI, 1.6 to 4.2) for five cups or more. The trend in risk with dose was statistically significant (P < 0.001). Duration of coffee consumption was not associated with the risk of AMI. The RRs for daily coffee consumption were elevated across strata of various covariates, including age, smoking habits, cholesterol level, diabetes, and hypertension, with a particularly elevated (although not significantly heterogeneous) estimate in patients younger than 50 years (RR, 5.7; 95% CI, 3.0 to 10.9 for four or more cups/d). The RR in patients who drank four or more cups of coffee per day and were current smokers was 8.1 (95% CI, 5.1 to 13.0), suggesting an unfavorable effect on the combination of cigarette smoking and high coffee intake on the risk of AMI.

Adult↗

[Relationship between coffee and blood cholesterol in a sample of working women].

BACKGROUND: Experimental studies have demonstrated that unfiltered coffee increases cholesterolemia. In Spain, filtered coffee is mainly consumed and its effect on cholesterolemia is controversial. METHODS: The relationship between coffee intake and the serum levels of total cholesterol was transversally studied in a population of 609 women between 18 to 65 years in age. The questionnaire and analyses were carried out in the context of periodic health examination. RESULTS: The consumption of coffee was positively associated with cholesterolemia in subjects under 30 years of age (p < 0.01) and in the group from 30 to 45 years in age (p < 0.05). This association was found to be statistically significant on multivariant analysis (multiple lineal regression) after adjusting for age, body mass index, cholesterol consumed in the diet, smoking, alcohol consumption and physical activity. CONCLUSIONS: Coffee was found to increase cholesterolemia in the female population and therefore a reduction in coffee intake would be recommendable in hypercholesterolemic subjects.

Adolescent↗

[Psychologic study of experienced coffee effect].

In dealing with the psychological effects of coffee a distinction is drawn between three components of the subjective or experimential effect: the primary effect, which relates to the perception of the coffee beverage; the secondary effect, which stems from the ergotropic effect of coffee; and the tertiary effect, which is due to visceral sensations and which is a major contributor to the experience of digestability and wholesomeness. Results pertaining to these three components, their interaction, and their correlation with physiological and behavioral effects of coffee are discussed. The variability of research findings relating to the secondary effect is explained on the basis of the psychological activation theory. Relevant motivational, attitudinal, and moderator effects, which psychological coffee research will have to take into account, are described. Methods already available for psychological coffee research, including suitable techniques of experimentation and measurement, are presented together with three illustrative examples.

Attitude↗

Two-year toxicity/carcinogenicity study of fresh-brewed coffee in rats initially exposed in utero.

Fresh-brewed regular coffee at concentrations of 25, 50, and 100% was consumed ad libitum as the sole fluid intake of F1 Sprague-Dawley rats (55 male and 55 female/group), derived from P0-treated females which were provided 50% coffee for about 5 weeks prior to copulation and throughout gestation and lactation. P0 males, P0 control females, and two groups of F1 control rats received tap water. Ten rats/sex/level were killed and examined after 1 year; survivors were killed after 2 years. Smaller mean body weights (50 and 100% coffee concentrations) occurred with increased feed and liquid consumption. Mean serum alkaline phosphatase, bilirubin, BUN, and calcium values occasionally were elevated. Serum cholesterol levels at 2 years were elevated in males (25 and 100%) and at 1 and 2 years in females (100%). Bone calcium was slightly reduced in females consuming 25 or 100% coffee for 1 year, but not after 2 years. Treatment-related increases in relative weights of lungs, kidneys, liver, and epididymides were recorded. Significantly increased mortality was observed in females receiving 50 or 100% coffee. There also was some evidence of a relationship between coffee consumption and the number of primary tumor-bearing animals; however, this finding appeared ambiguous, dependent on the assumption that tumors were the probable cause of death.

Abnormalities, Drug-Induced↗

Caffeine reduction in coffee pulp through silage.

Silage tests to study reductions of antiphysiological compounds (caffeine and polyphenols) of fresh coffee pulp during the anaerobic fermentation were done. A concrete silo divided in compartments, with a total capacity of 9 tons of fresh material was utilized. The silage periods ranged between 99-224 days and the following materials were ensiled: 1) coffee pulp, 2) coffee pulp with sugar cane molasses, 3) coffee pulp with a mixture of molasses and ammonia and 4) screw pressed coffee pulp with molasses. Reductions in caffeine, total polyphenols and condensed polyphenols ranged between 13-63%, 28-70% and 51-81% respectively. It was concluded that in the case of coffee pulp, silage presents and ideal method to preserve the material and partially reduce the contents of antiphysiological compounds.

Journal Article↗

PCR method for the detection of potential ochratoxin-producing Aspergillus species in coffee beans.

Ochratoxin A (OA) is a nephrotoxic and carcinogenic mycotoxin that has been found in cereal and food commodities. Currently, Aspergillus carbonarius, A. niger and A. ochraceus have been recognized as the species responsible for OA in coffee beans. With the aim of developing multiplex-PCR for detection of these species in coffee bean samples, we first developed specific primers for A. niger detection. The primer designed (OPX7(372)) provided an amplicon of 372 pb in all A. niger stricto sensu isolates. The PCR assay developed for A. niger identification in pure culture was also successfully used for detecting this species in coffee beans. No cross-reaction was observed using DNA from coffee beans inoculated with closely related black aspergilli species. A multiplex-PCR method for detection of A. carbonarius, A. niger and A. ochraceus species in coffee beans was developed. From a single assay this method detected the amplicons of 809, 372, and 260 pb that represent the three most ochratoxigenic species found in coffee bean samples, i.e., A. carbonarius, A. niger and A. ochraceus, respectively.

Aspergillus↗

Biological detoxification of coffee husk by filamentous fungi using a solid state fermentation system.

Studies were carried out on detoxification of coffee husk in solid state fermentation using three different strains of Rhizopus, Phanerochaete, and Aspergillus sp. Fungal strains were selected by their ability to grow on a coffee husk extract-agar medium. Using R. arrizus LPB-79, the best results on the degradation of caffeine (87%) and tannins (65%) were obtained with pH 6.0 and moisture 60% in 6 days. When P. chrysosporium BK was used, maximum degradation of caffeine and tannins were 70.8 and 45%, respectively, with coffee husk having 65% moisture and pH 5.5 in 14 days. The Aspergillus strain, isolated from the coffee husk, showed best biomass formation on coffee husk extract-agar medium. Optimization assays were conducted using factorial design, and surface response experiments with Aspergillus sp. The best detoxification rates achieved were 92% for caffeine and 65% for tannins. The results showed good prospects of using these fungal strains, in particular Aspergillus sp., for the detoxification of coffee husk.

Journal Article↗

Flavoring components of raw monsooned arabica coffee and their changes during radiation processing.

Volatile aroma principles, nonvolatile taste constituents (caffeine and chlorogenic and caffeic acids), and glycosidically bound aroma compounds of monsooned and nonmonsooned raw arabica coffee were analyzed using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). Among the most potent odor active constituents known to contribute to the aroma of the green beans, 3-isopropyl-2-methoxypyrazine, 3-isobutyl-2-methoxypyrazine, 4-vinylguaiacol, beta-damascenone, (E)-2-nonenal, trans,trans-2,4-decadienal, phenylacetaldehyde, and 3-methylbutyric acid were detected by GC-MS in both samples. A decrease in content of methoxypyrazines and an increase in 4-vinylguaiacol and isoeugenol resulted in a dominant spicy note of monsooned coffee. These phenolic compounds exist partly as their glycosides, and their release from the bound precursors during monsooning accounted for their higher content in monsooned coffee. A considerable decrease in astringent chlorogenic acid as a consequence of hydrolysis to bitter caffeic acid was noted in monsooned coffee. Radiation processing of nonmonsooned beans at a dose of 5 kGy resulted in an increased rate of monsooning. At this dose a quantitative increase in most of the aroma active components could be observed in all samples studied. Hydrolysis of chlorogenic acid to caffeic acid was noted in radiation-processed monsooned coffee beans irrespective of whether the treatment was carried out before or after monsooning. These changes were, however, not observed in irradiated, nonmonsooned coffee beans, suggesting an enzymatic rather than a radiolytic cleavage of chlorogenic acid. A rationale behind the mechanism of monsooning and radiation-induced enhancement of the monsooning process is discussed.

Caffeic Acids↗

Activity-guided identification of a chemopreventive compound in coffee beverage using in vitro and in vivo techniques.

The aim of the present study was to apply an activity-guided screening procedure to coffee brew to identify a key chemopreventive compound by means of in vitro antioxidant tests as well as cell culture experiments and to prove the in vivo activity of that compound by an animal feeding experiment. Solvent fractionation, followed by multiple-step ultrafiltration, revealed that the polar coffee compounds with molecular weights below 1 kDa show the major inhibitory effect on the in vitro peroxidation of linoleic acid as well as the predominant chemopreventive enzyme modulating activity on the NADPH-cytochrome c reductase (CCR) and glutathione S-transferase (GST) in human intestinal Caco-2 cells. To identify the chemical structure of the most active antioxidants and chemopreventive compounds, the polar compounds were further separated by HPLC techniques, followed by the activity-guided screening of the individual HPLC fraction. These experiments demonstrated 5-chlorogenic acid to be the most powerful antioxidant in vitro, whereas, in contrast, chemopreventive effects on the GST activity were found for the N-methylpyridinium ion, the structure of which was elucidated by LC-MS and NMR experiments and confirmed by synthesis. The in vivo activities of coffee beverage and N-methylpyridinium ions were tested in a 15-day feeding experiment on rats. In the liver, feeding of 4.5% coffee beverage resulted in increases of GST and UDP-GT activities by 24 and 40% compared to animals fed the control diet (p > 0.05), respectively. Plasma total antioxidant capacity and plasma tocopherol were elevated in animals fed the coffee beverage and the N-methylpyridinium-containing diet. In summary, the results demonstrating a strong in vitro antioxidant activity for coffee were confirmed by the feeding study. Surprisingly, feeding of N-methylpyridinium also resulted in an increased total antioxidant capacity in the plasma. The data indicate that the mode of action demonstrated for N-methylpyridinium in biological systems is different from that in foods.

Animals↗

Determination of the 2H/1H and 15N/14N ratios of Alkylpyrazines from coffee beans (Coffea arabica L. and Coffea canephoravar. robusta) by isotope ratio mass spectrometry.

The delta15N(AIR) and delta2H(VSMOW) data for several alkylpyrazines formed during the roasting process of coffee are reported. Samples of commercially available roasted (n = 9) as well as self-roasted (n = 8) coffee beans (Coffea arabica L. and Coffea canephora var. robusta) of different origins were investigated. By use of extracts prepared by simultaneous distillation extraction (SDE) and subsequently fractionated by liquid chromatography on silica gel, on-line capillary gas chromatography-isotope ratio mass spectrometry was employed in the combustion (C) and pyrolysis (P) modes (HRGC-C/P-IRMS) to determine the delta15N(AIR) and delta2H(VSMOW) values, respectively. In addition to the constituents of coffee beans, data for commercial synthetic alkylpyrazines and substances declared to be "natural" were determined. The delta15N(AIR) data for coffee alkylpyrazines under study-2-ethyl-5-methylpyrazine (1) and 2-ethyl-6-methylpyrazine (2) (measured as sum 1/2), 2-ethyl-3-methylpyrazine (3), 2-methylpyrazine (4), 2,5-dimethylpyrazine (5) and 2,6-dimethylpyrazine (6) (measured as sum 5/6), and 2,3-dimethylpyrazine (7), as well as 2,3,5-trimethylpyrazine (8)-varied in the range from +8.3 to -10.2 per thousand, thus revealing their biogeneration from amino acids (delta15N(AIR) ranging from +8 per thousand to -10 per thousand). The delta2H(VSMOW) values were determined in the range from -5 per thousand to -127 per thousand. Owing to the analytical differentiation observed between coffee alkylpyrazines and synthetic/"natural" samples of 3, 4, and 7, authenticity assessment of coffee-flavored products seems to be promising, provided that extended data will be available in the future. In the literature, there were no IRMS data available for the alkylpyrazines (1-8) under study.

Coffea↗

Modeling the secondary shelf life of ground roasted coffee.

This work was addressed to study the secondary shelf life of ground roasted coffee. To this purpose, fresh dark-roasted ground coffee samples were equilibrated at increasing water activity (aw) values up to 0.44 and stored at 30 degrees C for up to 1 month. To simulate home storage conditions, the headspace atmosphere was periodically perturbed by opening for a short time and then closing the packaging. The changes of some chemical and physicochemical indexes of coffee staling were studied, and sensory analysis was carried out to determine the end point of coffee acceptability. The results showed that the volatile compounds in the headspace are representative indexes of the quality depletion of roasted ground coffee during home usage. The sensory and instrumental results were used to develop a mathematical model allowing to simply and quickly calculate the secondary shelf life of coffee on the basis of its aw value at a given temperature.

Chemical Phenomena↗

Detection and quantification of Aspergillus ochraceus in green coffee by PCR.

AIMS: The aim of this study was to detect and quantify DNA of the ochratoxinogenic fungus Aspergillus ochraceus in green coffee and to compare the results with the ochratoxin A content of naturally contaminated samples. METHODS AND RESULTS: A DNA extraction protocol based on a combination of ultrasonification and a commercial kit was tested for the recovery of fungal DNA. PCR and real-time PCR protocols were established for the detection of A. ochraceus. Sensitivity of the PCR was checked by the addition of inoculated green coffee and pure fungal DNA to uncontaminated green coffee samples. The A. ochraceus DNA content of 30 naturally contaminated green coffee samples was determined and compared with the ochratoxin A concentrations. CONCLUSIONS: Aspergillus ochraceus can be rapidly and specifically detected in green coffee by PCR. A positive correlation between the ochratoxin A content and the DNA quantity was established. SIGNIFICANCE AND IMPACT OF THE STUDY: This work offers a quick alternative to the conventional mycological detection and quantification of A. ochraceus in green coffee.

Aspergillus ochraceus↗

The apolipoprotein E polymorphism and the cholesterol-raising effect of coffee.

BACKGROUND: The response of serum cholesterol to diet may be affected by the apolipoprotein E (APOE) epsilon2/epsilon3/epsilon4 polymorphism, which also is a significant predictor of variation in the risk of coronary heart disease (CHD) and CHD death. Here, we test the hypothesis that the APOE polymorphism may modulate the cholesterol-raising effect of coffee. OBJECTIVE: We determined the effect of a coffee abstention period and a daily intake of 600 mL coffee on serum cholesterol and triglycerides with respect to the APOE polymorphism. DESIGN: 121 healthy, non-smoking men (22%) and women (78%) aged 29-65 years, took part in a study with four intervention periods: 1 and 3) a coffee free period of three weeks, 2 and 4) 600 mL coffee/day for four weeks. RESULTS: APOE epsilon2 positive individuals had significantly lower total cholesterol concentration at baseline (4.68 mmol/L and 5.28 mmol/L, respectively, p = 0.01), but the cholesterol-raising effect of coffee was not influenced significantly by APOE allele carrier status. CONCLUSIONS: The APOE epsilon 2 allele is associated with lower serum cholesterol concentration. However, the APOE polymorphism does not seem to influence the cholesterol-raising effect of coffee.

Journal Article↗

Chemical and sensory profiling of fermented, washed, and artificially flavored coffee beans: Insights into flavour quality, authenticity, and food safety implications.

This study establishes an integrated framework combining chemical profiling, sensory analysis, and molecular mechanism evaluation to compare flavour quality and authenticity among fermented, washed, and artificially flavored coffees. GC&#xa0;&#xd7;&#xa0;GC-TOF-MS and UHPLC-HRMS showed that fermented samples had markedly higher ester and aromatic alcohol levels (total esters 74.5&#xa0;&#xb1;&#xa0;7.8&#xa0;mg&#xa0;kg-1; phenylethanol 27.5&#xa0;&#xb1;&#xa0;3.2&#xa0;mg&#xa0;kg-1, p&#xa0;<&#xa0;0.01), enhancing fruity-floral notes. Washed coffees contained the highest organic acid concentrations (45.2&#xa0;&#xb1;&#xa0;3.8&#xa0;mg&#xa0;kg-1, p&#xa0;<&#xa0;0.01), supporting brightness and umami. Artificially flavored coffees exhibited elevated exogenous aromatics (vanillin 21.5&#xa0;&#xb1;&#xa0;3.1&#xa0;mg&#xa0;kg-1) but significantly fewer Maillard products (p&#xa0;<&#xa0;0.05) and reduced flavour retention (55% after 14 days). Molecular docking revealed higher theoretical binding affinities for naturally generated compounds, suggesting a potential molecular basis for their greater sensory persistence. The framework supports constructing coffee quality fingerprints and verifying flavour authenticity.

Flavoring Agents↗

Coffee intake and risk of hypertension: the Johns Hopkins precursors study.

BACKGROUND: Whether the increase in blood pressure with coffee drinking seen in clinical trials persists over time and translates into an increased incidence of hypertension is not known. METHODS: We assessed coffee intake in a cohort of 1017 white male former medical students (mean age, 26 years) in graduating classes from 1948 to 1964 up to 11 times over a median follow-up of 33 years. Blood pressure and incidence of hypertension were determined annually by self-report, demonstrated to be accurate in this cohort. RESULTS: Consumption of 1 cup of coffee a day raised systolic blood pressure by 0.19 mm Hg (95% confidence interval, 0.02-0.35) and diastolic pressure by 0.27 mm Hg (95% confidence interval, 0.15-0.39) after adjustment for parental incidence of hypertension and time-dependent body mass index, cigarette smoking, alcohol drinking, and physical activity in analyses using generalized estimating equations. Compared with nondrinkers at baseline, coffee drinkers had a greater incidence of hypertension during follow-up (18.8% vs. 28.3%; P =.03). Relative risk (95% confidence interval) of hypertension associated with drinking 5 or more cups a day was 1.35 (0.87-2.08) for baseline intake and 1.60 (1.06-2.40) for intake over follow-up. After adjustment for the variables listed above, however, these associations were not statistically significant. CONCLUSION: Over many years of follow-up, coffee drinking is associated with small increases in blood pressure, but appears to play a small role in the development of hypertension.

Adult↗

Coffee-associated osteoporosis offset by daily milk consumption. The Rancho Bernardo Study.

OBJECTIVE: To describe the association of lifetime intake of caffeinated coffee, in cup-years, to bone mineral density (BMD) of the hip and spine in postmenopausal women; and to determine the effect of regular milk intake on this association. DESIGN: Women from an established epidemiologic cohort had measures of BMD and gave a medical and behavioral history that included caffeinated coffee and daily milk intake between the ages of 12 and 18 years, 20 and 50 years, and 50 years of age and older. SETTING: A community-based population of older women, Rancho Bernardo, Calif. PARTICIPANTS: All 980 postmenopausal women aged 50 to 98 years (mean age, 72.7 years) who participated between 1988 and 1991. MAIN OUTCOME MEASURES: Bone density at the hip and lumbar spine measured by dual energy x-ray absorptiometry. MAIN RESULTS: There was a statistically significant graded association between increasing lifetime intake of caffeinated coffee and decreasing BMD at both the hip and spine, independent of age, obesity, parity, years since menopause, and the use of tobacco, alcohol, estrogen, thiazides, and calcium supplements. Bone density did not vary by lifetime coffee intake in women who reported drinking at least one glass of milk per day during most of their adult lives. CONCLUSIONS: Lifetime caffeinated coffee intake equivalent to two cups per day is associated with decreased bone density in older women who do not drink milk on a daily basis.

Aged↗