Coffee consumption might be associated with lower potential risk and severity of metabolic syndrome: national health and nutrition examination survey 2003-2018.

BACKGROUND: Metabolic syndrome (MetS) is a clinical syndrome characterized by multiple metabolic disorders and is a serious global health problem. The coffee effect, acting as one of the most prevalent beverages on metabolic syndrome, is debatable. METHODS: We included patients from the National Health and Nutrition Examination Survey 2003-2018 and used a comprehensive evaluation called the MetS z-score to assess the severity of metabolic syndrome. The relationship between coffee, decaffeinated coffee, tea, and MetS z-scores was explored using a weighted linear regression. We also divided the participants into metabolic and non-metabolic syndrome groups according to the NCEP/ATP III criteria for the subgroup analysis. RESULTS: A total of 14,504 participants were included in this study. The results demonstrated that drinking more than three cups of coffee daily was significantly linked to lower MetS z-scores (p < 0.001). Daily coffee consumption was also associated with lower BMI (p = 0.02), systolic blood pressure (p < 0.001), Homeostatic Model Assessment for Insulin Resistance (p < 0.001), and triglycerides (p < 0.001), while it was positively correlated with HDL-C (p = 0.001). Participants who consumed more than three cups of coffee daily had a lower MetS z-score in the MetS (p < 0.001) and non-MetS (p = 0.04) groups. CONCLUSION: This research indicates that coffee consumption is linked to MetS severity. However, decaffeinated coffee and tea intake were unrelated to MetS severity.

The impact of altering the concentration of coffee constituents on their anticancer effect on oral squamous cell carcinoma cell line - in vitro study.

Introduction: Oral squamous cell carcinoma (OSCC) is one of the most common malignancies of the head and neck, which attracts much attention because of its increasing incidence and poor outcome. Coffee is one of the most popular beverages that are globally consumed. It consists of several phytochemical constituents, such as polyphenols, caffeine, and chlorogenic acid (CGA). Those constituents account for the potential effects on several diseases, including cancer. It has been reported that coffee exerts significant cytotoxicity against OSCC via inhibition of epidermal growth factor receptor tyrosine kinase (EGFR-TK) and up-regulation of apoptotic proteins, such as caspase-3 and caspase-9. The current study aims to measure the concentration of caffeine and CGA in 3 different types of coffee extracts, unroasted green coffee (GC), medium-roasted coffee (MRC), and decaffeinated coffee. Material and methods: The cytotoxic effect against OSCC-25 cell lines was evaluated and correlated with the concentration of constituents in each extract. The mechanisms of cytotoxicity were also studied by assessing the effect of each extract on caspase-3 and caspase-9 levels, in addition to the inhibitory effect on EGFR-TK. Results: It was found that the caffeine concentration was higher in MRC than in GC because of the roasting process. However, the concentration of caspase-3 and -9 and the inhibitory effect on EGFR-TK were much higher in GC than MRC-treated cells because of the higher concentration of CGA. Conclusions: Decaffeinated coffee exerts lower cytotoxic effects because it was totally deprived of caffeine and CGA during the decaffeination process.

Exploring the connection between caffeine intake and constipation: a cross-sectional study using national health and nutrition examination survey data.

BACKGROUND: Caffeine has been reported to increase gastrointestinal motility and change intestinal microbiota. Constipation may be caused by colonic motor dysfunction and colonic microbiomeis disturbances. In this study, we aimed to explore the association between caffeine intake and constipation. METHODS: This was a cross-sectional study based on the National Health and Nutrition Examination Survey (NHANES). Caffeine intake was assessed using 24-h dietary recall method, and constipation was defined based on stool consistency or stool frequency. Logistic regression analysis was used to assess the association between caffeine intake and constipation, and results were expressed as odds ratio (OR) with 95% confidence intervals (95%CI). Subgroup analysis was performed based on age. RESULTS: A total of 13,816 participants were finally included for analysis. After adjusting potential confounders, high intake of caffeine was found to be associated with the low odds of constipation (Q3: OR = 0.60, 95%CI: 0.49-0.74; Q4: OR = 0.77, 95%CI: 0.59-0.99; Q5: OR = 0.72, 95%CI: 0.56-0.92). The similar association was found in young people and middle-age people (P < 0.05). CONCLUSION: High caffeine intake was associated with the low odds of constipation. Our finding indicated that individuals should develop consciousness and habit of consuming caffeinated foods and drinks to prevent and relief the constipation.

Coffee consumption and all-cause and cardiovascular mortality in older adults: should we consider cognitive function?

Background: The association between coffee and mortality risk has been found in most previous studies, and recent studies have found an association between coffee consumption and cognition. However, there is still a lack of research exploring whether the association between coffee and mortality is influenced by cognitive function. Objective: The purpose of this study was to explore the association of coffee, caffeine intake in coffee and decaffeinated coffee with all-cause mortality and cardiovascular disease (CVD) mortality in older adults with different cognitive performances. Methods: The study was based on data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Coffee and caffeine consumption data were obtained from two 24-h dietary recalls. Individual cognitive functions were assessed by CERAD-word learning test (CERAD-WLT), animal fluency test (AFT), and digit symbol substitution test (DSST). In addition, principal component analysis (PCA) was performed with the above test scores to create global cognitive score. The lowest quartile of scores was used to classify cognitive performance. Cox regression and restricted cubic spline (RCS) were applied to assess the relationship between coffee and caffeine consumption and mortality. Results: In the joint effects analysis, we found that those with cognitive impairment and who reported without drinking coffee had the highest risk of all-cause and cardiovascular mortality compared with others. In the analysis of population with cognitive impairment, for all-cause mortality, those who showed cognitive impairment in the AFT displayed a significant negative association between their total coffee consumption and mortality {T3 (HR [95% CI]), 0.495 [0.291-0.840], p = 0.021 (trend analysis)}. For DSST and global cognition, similar results were observed. Whereas for CERAD-WLT, restricted cubic spline (RCS) showed a "U-shaped" association between coffee consumption and mortality. For CVD mortality, a significant negative trend in coffee consumption and death was observed only in people with cognitive impairment in AFT or DSST. In addition, we observed that decaffeinated coffee was associated with reduced mortality in people with cognitive impairment. Conclusion: Our study suggested that the association between coffee consumption and mortality is influenced by cognition and varies with cognitive impairment in different cognitive domains.

Association between coffee intake and frailty among older American adults: A population-based cross-sectional study.

Objective: We aimed to investigate the association between coffee consumption and frailty in older American adults. We focused on individuals at higher frailty risk, such as women, ethnic minorities, smokers, and those with obesity and insufficient physical activity. Methods: The data of 8,087 individuals aged over 60 years from the 2007-2018 National Health and Nutrition Examination Surveys were used for this cross-sectional study. The coffee drinks were classified into two categories: caffeinated and decaffeinated. Frailty was measured using the 53-item frailty index. Weighted binary logistic regression was used to evaluate the association between coffee intake and frailty risk. Restricted cubic spline models were used to assess the dose-response relationship between caffeinated coffee intake and frailty. Results: Among the 8,087 participants, 2,458 (30.4%) had frailty. Compared with those who reported no coffee consumption, the odds ratios [ORs; 95% confidence intervals (CIs)] of total coffee consumption > 498.9 (g/day) were 0.65 (0.52, 0.79) in the fully adjusted model. Compared with those who reported no caffeinated coffee consumption, the ORs (95% CIs) of total coffee consumption > 488.4 (g/day) were 0.68 (0.54, 0.85) in the fully adjusted model. Compared with those who reported no decaffeinated coffee consumption, the ORs (95% CIs) of total coffee consumption > 0 (g/day) were 0.87 (0.71, 1.06) in the fully adjusted model. Nonlinear associations were detected between total coffee and caffeinated coffee consumption and frailty. In the subgroup analyses by smoking status, the association between coffee consumption and the risk of frailty was more pronounced in non-smokers (P for interaction = 0.031). Conclusion: Caffeinated coffee consumption was independently and nonlinearly associated with frailty, especially in non-smokers. However, decaffeinated coffee consumption was not associated with frailty.

Morphological changes in retinochoroidal microvasculature after caffeinated versus decaffeinated coffee consumption.

BACKGROUND: To investigate changes in retinochoroidal microvascular morphology after caffeinated versus decaffeinated coffee consumption in age- and gender-matched healthy individuals using optical coherence tomography (OCT) and OCT angiography (OCTA). METHODS: In this prospective, randomized clinical study, a staff member in charge of record keeping randomly assigned 48 healthy volunteers to two groups: caffeinated coffee consumers (24 eyes) and decaffeinated coffee consumers (24 eyes). Participants' ages and genders were recorded before consumption, and a comprehensive ophthalmologic exam was performed, followed by OCT and OCTA analyses before, 30 min, one, six, and 24 h after blindly consuming either of the coffees. RESULTS: Caffeinated and decaffeinated coffee consumers had mean ages of 23.45 ± 0.92 and 22.73 ± 1.13, respectively (p = 0.407). The following parameters changed significantly in caffeinated coffee consumers 30 min and 1 h post-consumption (pre-consumption versus 30 min versus one hour post-consumption; p < 0.05): a) parafoveal superficial capillary plexus vessel density (%): 54.45 versus 51.8 versus 51.92, b) parafoveal deep capillary plexus vessel density (%): 55.16 versus 52.45 versus 52.83, c) outer retinal flow area (%): 8.87 ± 1.91 versus 8.03 ± 1.88 versus 8.11 ± 1.93, d) choriocapillaris flow area (mm2): 20.95 ± 0.98 versus 19.82 ± 1.20 a versus 19.62 ± 0.95, and e) sub-foveal choroidal thickness (µm): 295.06 ± 5.45 versus 277.08 ± 5.33 versus 260.71 ± 58.61. No significant differences in any OCT and OCTA parameters were found between consecutive measurements in decaffeinated coffee consumers (p > 0.05). CONCLUSIONS: Caffeinated coffee appears to transiently reduce parafoveal vessel density, capillary flow area, and sub-foveal choroidal thickness. Lack of these microvascular morphological changes in decaffeinated coffee suggests a potential caffeine-induced vasoconstrictive effect.

Association of Coffee, Tea, and Caffeine Consumption With All-Cause Risk and Specific Mortality for Cardiovascular Disease Patients.

Aim: The aim of the study was to examine the relationship between coffee, tea, caffeine consumption and risk of all-cause death and cardiovascular disease (CVD) death in CVD population. Methods: This cohort study included 626 CVD participants aged ≥18 years old who derived from the National Health and Nutrition Examination Surveys (NHANES) database 2003-2006. The end time of follow-up was 2015, and with a median follow-up time of 113.5 (63, 133) months. CVD death was defined as a death caused by congestive heart failure (CHF), coronary heart disease (CHD), angina pectoris, heart attack or stroke. Cox model and competitive-risk model were used to explore the relationship of coffee, tea, caffeine, decaffeinated coffee/tea on the risk of the all-cause death and CVD death for CVD population, respectively. Additionally, we explored the effect of urinary caffeine and caffeine metabolites on all-cause death. Results: All patients were divided into survival group (n = 304), non-CVD death group (n = 223), and CVD death group (n = 99). The incidence of all-cause death and CVD death was ~51.44 and 15.81% in the study. After adjusting age, body mass index (BMI), cancer, estimated glomerular filtration rate (eGFR), energy, the history of CVD medications, carbohydrate and family income to poverty ratio (PIR), the results suggested coffee, caffeine, iced tea and hot tea consumption (≥4 cups per day) were associated with an increased risk of the all-cause death in CVD patients; while hot tea (1-3 cups per day), decaffeinated coffee/iced tea/hot tea could reduce the risk of the all-cause death. Likewise, coffee, caffeine, iced tea (≥4 cups per day), hot tea, decaffeinated iced tea/ hot tea (Always) could enhance the risk of the CVD death in CVD population. We also found that 1-methylxanthine showed a significant positive association on the risk of all-cause death in CVD population. Conclusion: Our study indicated that higher consumption of coffee, tea and caffeine could increase the risk of all-cause and CVD death for CVD patients.

Effect of Caffeinated and Decaffeinated Coffee on Blood Pressure and Heart Rate of Healthy Individuals.

<b>Background and Objective:</b> Caffeine is the most widely consumed stimulant in the world with 80% of it consumed in the form of coffee. It is used as an ingredient in pharmaceuticals, owing to the high content of nutrients and antioxidants, including phenols and polyphenols, that have cardioprotective properties. This study aimed to investigate and compare the effects of caffeinated and decaffeinated coffee on blood pressure and heart rate. <b>Materials and Methods:</b> In this study, experimental days were divided over 2 weeks: February 21 to March 6. Each week, the participants were provided with a specific type of coffee to drink. They were advised to avoid exercise and vigorous physical activity and to get enough sleep. Blood pressure and heart rate were measured in resting/sitting position from the left arm using a blood pressure device, OMRON Model BP5100. The participants were clear of any cardiovascular diseases or hypertension. Any participants, who suffered from hypertension or hypotension were excluded. <b>Results:</b> We compared the impact of coffee with caffeine and without caffeine on systolic and diastolic blood pressure and heart rate. No difference in heart rates or blood pressure was observed in participants after 30-90 min of drinking either caffeinated or decaffeinated coffee. <b>Conclusion:</b> Based on the tests performed on 40 participants, we conclude that there are no significant differences in the influence of either type of coffee on blood pressure or heart rate.

The Impact of Instant Coffee and Decaffeinated Coffee on the Gut Microbiota and Depression-Like Behaviors of Sleep-Deprived Rats.

Objective: Based on our previous research, chronic paradoxical sleep deprivation (PSD) can cause depression-like behaviors and microbial changes in gut microbiota. Coffee, as the world's most popular drink for the lack of sleep, is beneficial to health and attention and can eliminate the cognitive sequelae caused by poor sleep. The purpose of this study is to investigate the effects of coffee and decaffeinated coffee on PSD rats. Research Design and Methods: A total of 32 rats were divided into four groups: control group, PSD model group, conventional coffee group, and decaffeinated coffee group. Behavioral tests, including sucrose preference test, open field test, forced swimming test, and tail suspension test, as well as biochemical detection for inflammatory and antioxidant indexes were performed. The effects of coffee and decaffeinated coffee on the gut microbiota of PSD rats were investigated by 16S rRNA gene sequencing. Results: Coffee and decaffeinated coffee significantly improved the depression-like behaviors. Moreover, the serum levels of interleukin-6 and tumor necrosis factor alpha were decreased in both coffee and decaffeinated coffee groups, as well as the levels of superoxide dismutase and GSH-Px were increased. Gut microbiota analysis revealed that the abundance of S24-7, Lachnospiraceae, Oscillospira, and Parabacteroides were significantly increased in PSD rats, while the abundance of Akkermansia and Klebsiella were significantly decreased. After the treatment of coffee and decaffeinated coffee, the abundance of the above gut microbiota was all restored in different degrees. Coffee had relatively more significant effects on PSD-induced depressive-like behaviors, while the difference between coffee and decaffeinated coffee was not obvious in correcting the disorder of gut microbiota. Conclusions: These findings have shown that both coffee and decaffeinated coffee are effective for sleep deprivation-induced depression-like behaviors and the dysbiosis of gut microbiota and indicated that caffeine may be not the only key substance of coffee for regulating gut microbiota.

Effects of Caffeinated and Decaffeinated Coffee Consumption on Metabolic Syndrome Parameters: A Systematic Review and Meta-Analysis of Data from Randomised Controlled Trials.

Coffee is rich in phenolic acids, such as caffeic acid and chlorogenic acid (CGA). Polyphenol-rich diets were shown to reduce the risk of metabolic syndrome (MeTS). Background and Objectives: This systematic review and meta-analysis discusses the effects of coffee consumption and its dose-response on MeTS parameters. Materials and Methods: PubMed and Scopus® were searched for relevant articles published between 2015 and 2020. This review focused on randomised controlled trials (RCTs) investigating the effect of coffee consumption on anthropometric measurements, glycaemic indices, lipid profiles, and blood pressure. Data from relevant studies were extracted and analysed using random, fixed, or pooled effects models with 95% confidence intervals (CIs). Results: Green coffee extract (GCE) supplementation (180 to 376 mg) was found to reduce waist circumference (weighted mean difference (WMD) = -0.39; 95% CI: -0.68, -0.10), triglyceride levels (WMD = -0.27; 95% CI: -0.43, -0.10), high-density lipoprotein-cholesterol levels (WMD = 0.62; 95% CI: 0.34, 0.90), systolic blood pressure (WMD = -0.44; 95% CI: -0.57, -0.32), and diastolic blood pressure (WMD = -0.83; 95% CI: -1.40, -0.26). Decaffeinated coffee (510.6 mg) reduced fasting blood glucose levels (WMD = -0.81; 95% CI: -1.65, 0.03). The meta-analysis showed that the intake of GCE containing 180 to 376 mg of CGA (administered in a capsule) and liquid decaffeinated coffee containing 510.6 mg of CGA improved the MeTS outcomes in study participants. Conclusions: The findings of the review suggested that the effect of coffee on MeTS parameters varies depending on the types and doses of coffee administered. A more detailed RCT on specific coffee doses (with adjustment for energy and polyphenol intake) and physical activity is needed to further confirm the observed outcomes.

Cardiovascular symptoms affect the patterns of habitual coffee consumption.

BACKGROUND: Excessive coffee consumption can lead to unpleasant sensations such as tachycardia and heart palpitations. OBJECTIVES: Our aim was to investigate if cardiovascular symptoms can lead to alterations in habitual patterns of coffee consumption. METHODS: We used information from up to 390,435 European ancestry participants in the UK Biobank, aged 39-73 y. Habitual coffee consumption was self-reported, and systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate were measured at baseline. Cardiovascular symptoms at baseline were based on hospital diagnoses, primary care records, and/or self-report. Mendelian randomization (MR) was used to examine genetic evidence for a causal association between SBP, DBP, and heart rate with habitual coffee consumption. RESULTS: Participants with essential hypertension, angina, or heart arrhythmia were all more likely to drink less caffeinated coffee and to be non-habitual or decaffeinated coffee drinkers compared with those who did not report related symptoms (P ≤ 3.5 × 10-8 for all comparisons). Higher SBP and DBP were associated with lower caffeinated coffee consumption at baseline, with consistent genetic evidence to support a causal explanation across all methods [MR-Egger regression (MREggr) ß: -0.21 cups/d (95% CI: -0.34, -0.07) per 10 mm Hg higher SBP and -0.33 (-0.61, -0.07) per 10 mm Hg higher DBP)]. In genetic analyses, higher resting heart rate was associated with a greater odds of being a decaffeinated coffee drinker (MREggr OR: 1.71; 95% CI: 1.31, 2.21) per 10 beats/min). CONCLUSIONS: We provide causal genetic evidence for cardiovascular system-driven influences on habitual coffee intakes, suggesting that people tend to naturally regulate their coffee consumption based on blood pressure levels and heart rate. These findings suggest that observational studies of habitual coffee intakes are prone to influences by reverse causation, and caution is required when inferred health benefits result from comparisons with coffee abstainers or decaffeinated coffee drinkers.

Coffee consumption and risk of renal cell carcinoma in the NIH-AARP Diet and Health Study.

BACKGROUND: Coffee consumption has been associated with a reduced risk of some cancers, but the evidence for renal cell carcinoma (RCC) is inconclusive. We investigated the relationship between coffee and RCC within a large cohort. METHODS: Coffee intake was assessed at baseline in the National Institutes of Health-American Association of Retired Persons Diet and Health Study. Among 420 118 participants eligible for analysis, 2674 incident cases were identified. We fitted Cox-regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for coffee consumption vs non-drinkers. RESULTS: We observed HRs of 0.94 (95% CI 0.81, 1.09), 0.94 (0.81, 1.09), 0.80 (0.70, 0.92) and 0.77 (0.66, 0.90) for usual coffee intake of <1, 1, 2-3 and ≥4 cups/day, respectively (Ptrend = 0.00003). This relationship was observed among never-smokers (≥4 cups/day: HR 0.62, 95% CI 0.46, 0.83; Ptrend = 0.000003) but not ever-smokers (HR 0.85, 95% CI 0.70, 1.05; Ptrend = 0.35; Pinteraction = 0.0009) and remained in analyses restricted to cases diagnosed >10 years after baseline (HR 0.65, 95% CI 0.51, 0.82; Ptrend = 0.0005). Associations were similar between subgroups who drank predominately caffeinated or decaffeinated coffee (Pinteraction = 0.74). CONCLUSION: In this investigation of coffee and RCC, to our knowledge the largest to date, we observed a 20% reduced risk for intake of ≥2 cups/day vs not drinking. Our findings add RCC to the growing list of cancers for which coffee consumption may be protective.

Decaffeinated coffee and its benefits on health: focus on systemic disorders.

The current literature has mainly focused on benefits and risks deriving from the consumption of caffeinated coffee and its implications for inflammation, cardiovascular diseases, neurodegenerative disorders, and cancer. Today, data about the role of caffeine in many disorders are controversial and the attention has increasingly focused on decaffeinated coffee and its non-caffeine compounds, which could have mainly beneficial effects. In fact, coffee phenolic compounds not only exhibit well-known antioxidant properties, but they can also antagonize some negative effects of caffeine, for example in inflammatory pathway and in glucose metabolism and homeostasis. In this review, we consider the literature of the last two decades and critically discuss the effects of decaffeinated coffee compounds on systemic disorders, mainly inflammation, cardiovascular diseases, hepatic dysfunctions, and cancer.

Association of Coffee, Decaffeinated Coffee and Caffeine Intake from Coffee with Cognitive Performance in Older Adults: National Health and Nutrition Examination Survey (NHANES) 2011-2014.

The aim of this study was to examine the association of coffee, caffeinated coffee, decaffeinated coffee and caffeine intake from coffee with cognitive performance in older adults. we used data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Coffee and caffeine intake were obtained through two 24-hour dietary recalls. Cognitive performance was evaluated by the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) test, Animal Fluency test and Digit Symbol Substitution Test (DSST). Binary logistic regression and restricted cubic spline models were applied to evaluate the association of coffee and caffeine intake with cognitive performance. A total of 2513 participants aged 60 years or older were included. In the fully adjusted model, compared to those reporting no coffee consumption, those who reported 266.4-495 (g/day) had a multivariate adjusted odd ratio (OR) with 95% confidence interval (CI) of 0.56(0.35-0.89) for DSST test score, compared to those reporting no caffeinated coffee consumption, those who reported ≥384.8 (g/day) had a multivariate-adjusted OR (95% CI) of 0.68(0.48-0.97) for DSST test score, compared to the lowest quartile of caffeine intake from coffee, the multivariate adjusted OR (95% CI) of the quartile (Q) three was 0.62(0.38-0.98) for the CERAD test score. L-shaped associations were apparent for coffee, caffeinated coffee and caffeine from coffee with the DSST test score and CERAD test score. No significant association was observed between decaffeinated coffee and different dimensions of cognitive performance. Our study suggests that coffee, caffeinated coffee and caffeine from coffee were associated with cognitive performance, while decaffeinated coffee was not associated with cognitive performance.

An outlook on the role of decaffeinated coffee in neurodegenerative diseases.

Coffee is reported to be among the most widely consumed beverages in the world and coffee consumption has been associated with reductions in the risk of several chronic diseases. Among its constituents, caffeine represents the most investigated component. The main impact of caffeine on health is associated with the central nervous system, the cardiovascular system, the inflammatory mechanisms, the metabolism of carbohydrates, and the cancer. Current research is devoted to the role of this compound and its analogs or derivatives on neuroinflammation and neurodegenerative disorders, mainly Alzheimer's Disease and Parkinson's Disease. However, coffee is also rich in polyphenols, mainly phenolic acids (chlorogenic acids, caffeic acid, ferulic acid), quinic acid, and quercetin. Many aspects still require greater clarification, including the effect of coffee compounds different from caffeine, on several pathologies. This review aimed to provide a comprehensive overview of the potential benefits of decaffeinated coffee constituents, focusing the attention on neurological processes and pathologies, such as mainly memories disorders, Parkinson's Disease, neurophatic pain disorders, and cerebral ischemia.

The acute effects of decaffeinated versus caffeinated coffee on reaction time, mood and skeletal muscle strength.

Background Caffeinated coffee, a psycho-stimulant, is widely consumed throughout the globe. However, its chronic consumption has deleterious effects on human health. Meanwhile, decaffeinated coffee has low content of caffeine and thus can be an alternative to caffeinated coffee. Therefore, the study was undertaken to explore and compare the acute effects of decaffeinated and caffeinated coffee on reaction time, mood and skeletal muscle strength in healthy volunteers. Methods This was a prospective, interventional, comparative type of study. The study included 70 healthy adults divided into two groups (Caffeinated coffee group and Decaffeinated coffee group). The following parameters were assessed: reaction time was assessed by digital display multiple-choice apparatus, mood by Visual Analogue Scale (VAS) and Profile of Mood States revised version (POMS) and skeletal muscle strength by hand dynamometer. All parameters in both groups were assessed pre-intervention (baseline) and 30 min post-intervention. Results In both groups (decaffeinated and caffeinated coffee) post-intervention, there was a statistically significant (p < 0.05) improvement in the reaction time (VRT) and mood (VAS, POMS) from the baseline. However, both groups did not show any significant effects on the skeletal muscle strength. Upon comparing the two groups, we found that caffeinated coffee showed higher and significant improvement of mood than decaffeinated coffee. Conclusions Decaffeinated coffee exerts an acute significant stimulatory effect on the reaction time and mood. However, these effects in comparison to caffeinated coffee are low. Further randomized control clinical trials are thus needed to validate these interesting findings.

Coffee prevents fatty liver disease induced by a high-fat diet by modulating pathways of the gut-liver axis.

Coffee consumption is inversely associated with the risk of non-alcoholic fatty liver disease (NAFLD). A gap in the literature still exists concerning the intestinal mechanisms that are involved in the protective effect of coffee consumption towards NAFLD. In this study, twenty-four C57BL/6J mice were divided into three groups each receiving a standard diet, a high-fat diet (HFD) or an HFD plus decaffeinated coffee (HFD+COFFEE) for 12 weeks. Coffee supplementation reduced HFD-induced liver macrovesicular steatosis (P < 0·01) and serum cholesterol (P < 0·001), alanine aminotransferase and glucose (P < 0·05). Accordingly, liver PPAR- α (P < 0·05) and acyl-CoA oxidase-1 (P < 0·05) as well as duodenal ATP-binding cassette (ABC) subfamily A1 (ABCA1) and subfamily G1 (ABCG1) (P < 0·05) mRNA expressions increased with coffee consumption. Compared with HFD animals, HFD+COFFEE mice had more undigested lipids in the caecal content and higher free fatty acid receptor-1 mRNA expression in the duodenum and colon. Furthermore, they showed an up-regulation of duodenal and colonic zonulin-1 (P < 0·05), duodenal claudin (P < 0·05) and duodenal peptide YY (P < 0·05) mRNA as well as a higher abundance of Alcaligenaceae in the faeces (P < 0·05). HFD+COFFEE mice had an energy intake comparable with HFD-fed mice but starting from the eighth intervention week they gained significantly less weight over time. Data altogether showed that coffee supplementation prevented HFD-induced NAFLD in mice by reducing hepatic fat deposition and metabolic derangement through modification of pathways underpinning liver fat oxidation, intestinal cholesterol efflux, energy metabolism and gut permeability. The hepatic and metabolic benefits induced by coffee were accompanied by changes in the gut microbiota.

Effect of decaffeinated coffee on function and nucleotide metabolism in kidney.

Little is known about the effects of coffee that are not related to the presence of caffeine. The aim of the study was to analyse changes in kidney function and nucleotide metabolism related to high intake of decaffeinated coffee. Mice consumed decaffeinated coffee extract for two weeks. Activities of AMP deaminase, ecto5'-nucleotidase, adenosine deaminase, purine nucleoside phosphorylase were measured in kidney cortex and medulla by analysis of conversion of substrates into products using HPLC. Concentration of nucleotides in kidney cortex, kidney medulla and serum were estimated by HPLC. Activity of ecto5'-nucleotidase increased from 0.032 ± 0.006 to 0.049 ± 0.014 nmol/mg tissue/min in kidney cortex of mice administered high-dose decaffeinated coffee (HDC) together with increase in cortex adenosine concentration and decrease in plasma creatinine concentration. HDC leads to increased activity of ecto5'-nucleotidase in kidney cortex that translates to increase in concentration of adenosine. Surprisingly this caused improved kidney excretion function.

Effect of Decaffeinated Coffee-enriched Chlorogenic Acid on Blood Glucose Levels in Healthy Controls: A Systematic Review.

As an important group of health problems, glucose metabolism disorders are associated with a number of diseases as well as mortality rate. Recently, studies have demonstrated that the consumption of decaffeinated coffee-enriched chlorogenic acid (CGA) can reduce the risk of diabetes and blood glucose rise, while the results of some previous studies have shown an opposite effect. Hence, a systematic search was conducted based on literature search and appropriate keywords through PubMed, Google Scholar, Web of Knowledge, Science direct, Medline, Cochrane, and Scopus databases from 2003 to 2018. After searching, 1593 articles were found. Then, we excluded papers based on the duplication and relevant for title and abstract, whereas 25 relevant articles remained for checking eligibility criteria. Since only randomized clinical trials studies (RCTs) could be included in the current study, six RCTs remained in end-stage for qualitative synthesis. The results of reviewed studies showed no significant effect of decaffeinated coffee-enriched CGA on blood glucose concentration. Although recent studies have suggested the effectiveness of decaffeinated coffee-enriched CGA on blood glucose in animals, and there are various mechanisms for this effect, and the result of our review showed that there is not sufficient evidence for this claim in healthy humans. Hence, further research in this area seems necessary.

Effect of explosion-puffed coffee on locomotor activity and behavioral patterns in Drosophila melanogaster.

We hypothesized that the administration of explosion-puffed coffee, containing γ-aminobutyric acid (GABA) and 5-hydroxytryptophan (5-HTP), would be associated with a reduction of the caffeine effect on sleep behavior and behavioral patterns, which was investigated in a Drosophila model. The effects of feeding roasted coffee beans (RB), explosion-puffed coffee beans puffed at 0.75MPa and 0.9MPa (PB 7.5 and PB 9.0, respectively), or decaffeinated coffee beans (DeRB) on locomotor activity and behavioral patterns of Drosophila was analyzed. In the decreasing order, the total chlorogenic acid (caffeoylquinic acids, CQA) content was PB 7.5>PB 9.0>RB. PB content analysis showed high levels of GABA and 5-HTP, compared with that of RB, which corresponded with the sleep-wake behavior of Drosophila. The RB and PB (PB 7.5 and PB 9.0) groups were not significantly different with respect to an activity count during the subjective night and day period compared with the normal controls. Sleep bout numbers of the normal, PB, and DeRB groups showed significant differences as compared with the caffeine and RB groups (p<0.05). The PB and DePB groups showed a significantly increased transcript levels for the GABA receptors compared to the caffeine group. The caffeine and RB groups displayed better climbing ability than the other groups, covering an average distance 6cm in the related test; the average distance covered by the normal, PB 7.5, and DeRB groups was <4cm. The normal and DeRB groups showed similar behavior patterns with respect to total distance, velocity, moving, not moving, and meander. However, the PB 7.5 group significantly regulated not moving and meander of flies compared to flies receiving only caffeine and RB. Suppression of the stimulating effect of caffeine by explosion-puffed coffee administration was indicated in the above results, which can be attributed to the increased content of GABA and 5-HTP with explosive puffing process carried out at 0.75MPa. Results of the underlying mechanism of the behavioral change patterns of explosive puffed with or without caffeine in Drosophila models, transcript level for the Dop1-R1 receptor in caffeine group was significantly higher than normal, PB, and DePB groups. Flies exposed to the caffeine had significantly decreased transcript levels for the GABA receptors. PB 7.5 and DePB showed higher level of GABA content than RB.