Boiled or Filtered Coffee?

Coffee Consumption and C-Reactive Protein Levels: A Systematic Review and Meta-Analysis

Coffee contains bioactive compounds with anti-inflammatory properties, and its consumption may reduce c-reactive protein (CRP) levels, a biomarker of chronic inflammation. A previous meta-analysis reported no overall association between blood CRP level and coffee consumption by modeling the coffee consumption in categories, with substantial heterogeneity. However, the coffee cup volume was not considered. We conducted a systematic review and dose–response meta-analysis investigating the association between coffee consumption and CRP levels reported in previous observational studies. A dose–response meta-analysis was conducted by mixed-effects meta-regression models using the volume of coffee consumed as metric. Eleven studies from three continents were identified using the PubMed database, totaling 61,047 participants. Three studies with the largest sample sizes observed a statistically significant association between coffee and CRP levels, which was inverse among European and United States (US) women and Japanese men (1.3–5.5% decrease in CRP per 100 mL of coffee consumed) and positive among European men (2.2% increase). Other studies showed no statistically significant associations. When all studies were combined in the dose–response meta-analysis, no statistically significant associations were observed among all participants or when stratified by gender or geographic location, reflecting the conflicting associations reported in the included studies. Further studies are warranted to explore these inconsistent associations.

Association between Coffee Consumption and Its Polyphenols with Cardiovascular Risk Factors: A Population-Based Study

Epidemiological studies have examined the effect of coffee intake on cardiovascular disease, but the benefits and risks for the cardiovascular system remain controversial. Our objective was to evaluate the association between coffee consumption and its polyphenols on cardiovascular risk factors. Data came from the “Health Survey of São Paulo (ISA-Capital)” among 557 individuals, in São Paulo, Brazil. Diet was assessed by two 24-h dietary recalls. Coffee consumption was categorized into <1, 1–3, and ≥3 cups/day. Polyphenol intake was calculated by matching food consumption data with the Phenol-Explorer database. Multiple logistic regression models were used to assess the associations between cardiovascular risk factors (blood pressure, total cholesterol, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), triglycerides, fasting glucose, and homocysteine) and usual coffee intake. The odds were lower among individuals who drank 1–3 cups of coffee/day to elevated systolic blood pressure (SBP) (Odds Ratio (OR) = 0.45; 95% Confidence Interval (95% CI): 0.26, 0.78), elevated diastolic blood pressure (DBP) (OR = 0.44; 95% CI: 0.20, 0.98), and hyperhomocysteinemia (OR = 0.32; 95% CI: 0.11, 0.93). Furthermore, significant inverse associations were also observed between moderate intake of coffee polyphenols and elevated SBP (OR = 0.46; 95% CI: 0.24, 0.87), elevated DBP (OR = 0.51; 95% CI: 0.26, 0.98), and hyperhomocysteinemia (OR = 0.29; 95% CI: 0.11, 0.78). In conclusion, coffee intake of 1–3 cups/day and its polyphenols were associated with lower odds of elevated SBP, DBP, and hyperhomocysteinemia. Thus, the moderate consumption of coffee, a polyphenol-rich beverage, could exert a protective effect against some cardiovascular risk factors.

Coffee Consumption Increases the Antioxidant Capacity of Plasma and Has No Effect on the Lipid Profile or Vascular Function in Healthy Adults in a Randomized Controlled Trial

BACKGROUND

Coffee, a source of antioxidants, has controversial effects on cardiovascular health.

OBJECTIVE

We evaluated the bioavailability of chlorogenic acids (CGAs) in 2 coffees and the effects of their consumption on the plasma antioxidant capacity (AC), the serum lipid profile, and the vascular function in healthy adults.

METHODS

Thirty-eight men and 37 women with a mean ± SD age of 38.5 ± 9 y and body mass index of 24.1 ± 2.6 kg/m(2) were randomly assigned to 3 groups: a control group that did not consume coffee or a placebo and 2 groups that consumed 400 mL coffee/d for 8 wk containing a medium (MCCGA; 420 mg) or high (HCCGA; 780 mg) CGA content. Both were low in diterpenes (0.83 mg/d) and caffeine (193 mg/d). Plasma caffeic and ferulic acid concentrations were measured by GC, and the plasma AC was evaluated with use of the ferric-reducing antioxidant power method. The serum lipid profile, nitric oxide (NO) plasma metabolites, vascular endothelial function (flow-mediated dilation; FMD), and blood pressure (BP) were evaluated.

RESULTS

After coffee consumption (1 h and 8 wk), caffeic and ferulic acid concentrations increased in the coffee-drinking groups, although the values of the 2 groups were significantly different (P < 0.001); caffeic and ferulic acid concentrations were undetectable in the control group. At 1 h after consumption, the plasma AC in the control group was significantly lower than the baseline value (-2%) and significantly increased in the MCCGA (6%) and HCCGA (5%) groups (P < 0.05). After 8 wk, no significant differences in the lipid, FMD, BP, or NO plasma metabolite values were observed between the groups.

CONCLUSIONS

Both coffees, which contained CGAs and were low in diterpenes and caffeine, provided bioavailable CGAs and had a positive acute effect on the plasma AC in healthy adults and no effect on blood lipids or vascular function. The group that did not drink coffee showed no improvement in serum lipid profile, FMD, BP, or NO plasma metabolites. This trial was registered at registroclinico.sld.cu as RPCEC00000168.

Cardiovascular effects of long-term caffeine administration in aged rats

AIM

To evaluate the possible beneficial effect of long-term caffeine administration on cardiovascular system in aged rats.

METHODS

This study was carried out on 20 senile male albino rats, aged 18-20 months. Rats were divided into caffeine-treated group, which received 25 mg/kg caffeine by gavage daily for 6 weeks, and control group. All rats were subjected to the following in vivo measurements: body weight, arterial blood pressure, heart rate and ECG recording. In vitro measurements included studying isolated hearts in a Langendorff apparatus for their intrinsic properties as well as plasma levels of lipids, malondialdehyde and nitrate.

RESULTS

Caffeine administration to aged rats significantly enhanced the baseline and maximum values achieved in response to isoproterenol infusion in isolated heart preparation for both maximum rate of tension development (dT/dt max) and time to peak tension (TPT). The responses of hearts isolated from caffeine group to the three doses of isoproterenol infusion also showed a significantly higher dT/dt max with shorter TPT and half relaxation time (1/2 RT) compared to controls. Plasma nitrate was significantly increased and ECG recording was nonsignificantly affected in caffeine group. The plasma levels of total cholesterol, LDL cholesterol as well as in vivo heart rate and systolic, diastolic and mean arterial blood pressures were all significantly increased associated with a significant decrease in HDL cholesterol in caffeine group.

CONCLUSION

Long-term caffeine administration in aged rats increased cardiac inotropy, lusitropy and preserved NO level, which points to a promising potential favorable effect on cardiac intrinsic properties.

Caffeine administration does not alter salivary α-amylase activity in young male daily caffeine consumers

BACKGROUND

To follow up on a recent report from our lab [Hum Psychopharmacol 25:359-367, 2010.] we examined the effects of caffeine on salivary α-amylase (sAA) activity in response to an engaging, non-stressful task in healthy young males (age 18-30 yrs) who consumed caffeine on a daily basis. Using a placebo-controlled, double-blind, between-subjects design, 45 men received either placebo, 200 mg or 400 mg of caffeine (Vivarin®). Participants then rested for 20 minutes, and performed a 20-minute computerized air traffic controller-like task that was cognitively engaging but not stressful. Saliva samples (assayed for sAA and cortisol), blood pressure, and heart rate were taken before (baseline) and 15 minutes after the computerized task.

RESULTS

Systolic and diastolic blood pressure and sAA activity increased across the laboratory session (F's > 9.20, p's < 0.05); salivary cortisol levels decreased (F = 16.17, p < 0.05). There were no main effects for caffeine administration on sAA, salivary cortisol, or cardiovascular measures, and caffeine did not interact with the task to alter these measures.

CONCLUSIONS

Laboratory administered caffeine does not alter sAA activity, even when sAA activity is stimulated by participating in a cognitively engaging task. These data demonstrate that caffeine administration does not affect sAA activity, at least in healthy young men who regularly consume caffeine. Results support recent findings that basal caffeine levels in habitual caffeine users are not associated with basal sAA activity and that daily caffeine intake and diurnal sAA activity are not related.

Effects of caffeine and stress on biomarkers of cardiovascular disease in healthy men and women with a family history of hypertension

The connection between caffeine and its potentially detrimental effects on blood markers of cardiovascular disease (CVD) are controversial. Most studies have focused on cholesterol as a putative mediator of the caffeine-CVD relationship. Other blood markers such as C-reactive protein (CRP) and fibrinogen have been understudied. We examined the effects of caffeine and psychological stress on these CVD markers in healthy, young men and women with a confirmed family history of hypertension. A total of 52 normotensive, healthy adults (26 men and 26 women) aged 18-29 years (21.4 ± 0.3) participated in a laboratory session to examine stress reactivity following caffeine consumption. All participants had normal cholesterol levels. Blood pressure (BP), heart rate, serum cortisol and CRP and plasma fibrinogen were collected. Men and women administered caffeine displayed an additional increase in systolic BP and cortisol response to the stressor (p < 0.05). Stress interacted with caffeine and sex to alter cortisol, fibrinogen and systolic BP but not CRP levels. These results may shed light on sex-specific pathways that associate caffeine with CVD.

Consumption of cocoa, tea and coffee and risk of cardiovascular disease

Daily intake of an anti-thrombotic diet may offer a suitable and effective way of coronary artery disease (CAD) prevention. A diet rich in fruit, vegetables, complex carbohydrates, monounsaturated fat and fish, moderate alcohol consumption but poor in salt, saturated fat and simple sugars, plays an important role in protect against CAD. Chocolate, coffee and tea, unfairly not included in "traditional healthy food basket", have received much attention over the past few years, if for no other reason than they are consumed worldwide and are important dietary sources of polyphenols (flavonols and cathechins). Several in vitro and in vivo studies have tried to elucidate the role of these foods and a large amount of experimental studies clearly indicated a beneficial effect of polyphenols in influencing CAD. However, data from epidemiological studies are not conclusive. The blood pressure lowering effects and the anti-inflammatory activity of dark chocolate suggests its use as potential prophylactic and therapeutic agent, in particular considering that epidemiological studies suggest that dark chocolate is inversely associated with CAD. Although regular consumption of moderate quantities of coffee and (green) tea seems to be associated with a small protection against CAD, results from randomized clinical trials about their beneficial effects are less evident. As for other diffuse consumption habits, such as that of alcohol, moderation is the key word. In fact, both for coffee and chocolate, the optimal healthy effects on CAD have been observed to be associated with a moderate intake, while healthy outcomes vanish at heavy consumption.

Caffeine and stress alter salivary alpha-amylase activity in young men

OBJECTIVE

We examined the effects of caffeine and a psychological stressor on salivary alpha-amylase (sAA) in healthy young males (age 18-30 years) who consumed caffeine on a daily basis.

METHODS

Using a between-subjects, double-blind, placebo-controlled design, 45 participants received either 200 or 400 mg of caffeine (Vivarin) or placebo, rested for 20 min, and then performed 20 min of mental arithmetic. Saliva samples (assayed for sAA and caffeine), blood pressure, and heart rate were taken before (baseline) and 15 min after the math stressor (stress).

RESULTS

Baseline sAA activity did not differ among the treatment groups; however, there was a statistically significant time by caffeine group interaction. Changes in sAA activity across the session were dependent on the amount of caffeine consumed. Following the challenge period, sAA activity among the placebo group was the lowest and sAA activity among the 400 mg treatment group was the highest. Separate repeated-measures ANOVAs conducted for each drug treatment group revealed that sAA activity increased in response to stress and caffeine (i.e., 200 and 400 mg groups) but not to stress alone (i.e., placebo group).

CONCLUSIONS

Findings provide evidence for acute sAA changes in response to caffeine and stress in habitual caffeine users.

Vestibular disorders among adults in a tertiary hospital in Lagos, Nigeria

Dizziness is not an uncommon complaint in the Otolaryngological clinics among other symptoms. To a large number of practitioners, the treatment of dizziness remains the same irrespective of the etiology, i.e., anti-vertiginous drugs. The objective of this study was to document the evaluation, causes and treatment of vestibular disorders among our patients. The design includes descriptive prospective study conducted in the Oto-rhino-laryngology and Orthopedic Clinics of Lagos University Teaching Hospital, Lagos and Nigerian Army Audiological Centre, 68 Nigerian Army Reference Hospital, Yaba, Lagos, Nigeria. Adult patients referred to the audiology clinic for dizziness had detailed history obtained by using structured questionnaire. General physical and neuro-otological examinations were done. Clinical diagnoses were made on standardized criteria. The patients had hearing evaluation, videonystagmography (VNG) evaluation using infrared videonystagmography system. X-ray of the cervical spine and computerized tomogram scan of internal auditory meatus and brain when indicated were done. A total of 102 patients were seen with age range between 21 and 90 years. Thirty patients (29.4%) recorded average duration of episode of vertiginous attacks in seconds, 69 (67.6%) recorded within minutes to hours and 3 (2.9%) with no definite pattern. Clinical signs on neuro-otological examination were elicited on 39 (38.2%) of the patients while on VNG the vestibular subtest mainly caloric test was abnormal unilaterally and bilaterally in 47 (46.1%) while with the oculomotor subtests, smooth pursuit tests were abnormal in 5 (6.9%), saccade tests were abnormal in 8 (7.8%) and OPK were abnormal in 9 (8.8%). Peripheral vestibular disorders are common of which benign paroxysmal positional vertigo (BPPV) was seen in 29 (28.4%), Meniere's disease in 22 (21.6%), recurrent vestibulopathy in 20 (19.6%), cervical vertigo in 18 (17.6%), psychogenic vertigo in 2 (2%), vestibular schwannoma, barotraumas and drug-induced vertigo in 1 (1%), respectively, central vestibular disorders of vascular origin 2 (2%), vertebrobasilar insufficiency in 1 (1%), post-traumatic vertigo in 3 (3%) and unknown in 2 (2%). In conclusion, peripheral vestibular disorders are common of which BPPV is the most prevalent. Pre-referral anti-vertiginous medication is common among general practitioners. The practising ORL/Head neck surgeon and orthopedic surgeons must be conversant with the tools of diagnosis, differential diagnosis and treatment.

Inflammatory effects of nutritional stimuli: further support for the need for a big picture approach to tackling obesity and chronic disease

The discovery of a form of low-grade systemic inflammation (called 'metaflammation'), and the close evolutionary link between the immune and metabolic systems, poses questions about the supposed antigens (inducers) of such an immune reaction. Initially, this was thought to be mediated through obesity. However, we have identified a number of lifestyle or environmentally related inducers that may cause metaflammation, even in the absence of obesity. In this paper, the third of a series linking obesity with broad environmental and evolutionary factors, we identify nutritional stimuli with evidence of an involvement in metaflammation. From this we propose that components of certain foods and beverages with which humans have not evolved, are more often the inducers of an inflammatory effect in the body than those with which humans have become more familiar, and to which a neutral, or anti-inflammatory response may be expected to have developed. The implications of such a finding are considered in relation to broader aspects of the environment, economic growth, policy change and current global financial issues.

Coffee consumption and risk of stroke in women

BACKGROUND

Data on the association between coffee consumption and risk of stroke are sparse. We assessed the association between coffee consumption and the risk of stroke over 24 years of follow-up in women.

METHODS AND RESULTS

We analyzed data from a prospective cohort of 83,076 women in the Nurses' Health Study without history of stroke, coronary heart disease, diabetes, or cancer at baseline. Coffee consumption was assessed first in 1980 and then repeatedly every 2 to 4 years, with follow-up through 2004. We documented 2280 strokes, of which 426 were hemorrhagic, 1224 were ischemic, and 630 were undetermined. In multivariable Cox regression models with adjustment for age, smoking status, body mass index, physical activity, alcohol intake, menopausal status, hormone replacement therapy, aspirin use, and dietary factors, the relative risks (RRs) of stroke across categories of coffee consumption (<1 cup per month, 1 per month to 4 per week, 5 to 7 per week, 2 to 3 per day, and >or=4 per day) were 1, 0.98 (95% CI, 0.84 to 1.15), 0.88 (95% CI, 0.77 to 1.02), 0.81 (95% CI, 0.70 to 0.95), and 0.80 (95% CI, 0.64 to 0.98) (P for trend=0.003). After further adjustment for high blood pressure, hypercholesterolemia, and type 2 diabetes, the inverse association remained significant. The association was stronger among never and past smokers (RR for >or=4 cups a day versus <1 cup a month, 0.57; 95% CI, 0.39 to 0.84) than among current smokers (RR for >or=4 cups a day versus <1 cup a month, 0.97; 95% CI, 0.63 to 1.48). Other drinks containing caffeine such as tea and caffeinated soft drinks were not associated with stroke. Decaffeinated coffee was associated with a trend toward lower risk of stroke after adjustment for caffeinated coffee consumption (RR for >or=2 cups a day versus <1 cup a month, 0.89; 95% CI, 0.73 to 1.08; P for trend=0.05).

CONCLUSIONS

Long-term coffee consumption was not associated with an increased risk of stroke in women. In contrast, our data suggest that coffee consumption may modestly reduce risk of stroke.

Effects of caffeine and coffee consumption on cardiovascular disease and risk factors

Clinical and observational studies have recently reported that coffee consumption is associated with cardiac arrhythmia, with increased serum cholesterol, blood pressure and affected heart rate variability, leading to an increased cardiovascular risk. Analysis of these papers shows that these data are controversial and strongly depend on methodology. Recent reports demonstrate the beneficial effects of coffee consumption due to anti-inflammatory actions mediated by antioxidant compound of the beverages.