Abstention from filtered coffee reduces the concentrations of plasma homocysteine and serum cholesterol--a randomized controlled trial

The effect of excessive coffee consumption, in relation to diterpenes levels of medium-roasted coffee, on non-high-density lipoprotein cholesterol level in healthy men

This study was designed to determine the levels of coffee oil and diterpenes and evaluate the correlation between the effect of excessive roasted coffee consumption on non-high-density lipoprotein cholesterol (non-HDL) and the roasting degree effect on the levels of coffee oil and diterpenes extracted from Coffea arabica. The coffee oil and diterpenes were extracted using soxhlet and liquid-liquid extraction. Sixty-six healthy normolipidemic male participants were assigned for this study which consisted of two stages. The first stage is the coffee abstaining stage where subjects were requested to abstain from drinking coffee for 2 weeks. The second stage is the coffee drinking stage which consisted of groups (the control group and coffee-drinking group). The levels of TC, TG, LDL-C, HDL-C, and non-HDL were determined in all participants before and after the experiment. The results indicated that the coffee roasting degree demonstrated a significant increase in the levels of coffee oil and diterpenes ranging from 9.31% (green coffee) to 15.64% (dark roast) and from 0.205% (green coffee) to 0.300% (dark roast) for diterpenes. In conclusion, the current study revealed that excessive consumption of medium roasted coffee was associated with elevated non-HDL levels in normotensive nonsmoker healthy men which might be attributed to the positive association between the degree of roasting and diterpenes levels.

Prediagnostic Plasma Metabolomics and the Risk of Exfoliation Glaucoma

Purpose

The etiology of exfoliation glaucoma (XFG) is poorly understood. We aimed to identify a prediagnostic plasma metabolomic signature associated with XFG.

Methods

We conducted a 1:1 matched case-control study nested within the Nurses' Health Study and Health Professionals Follow-up Study. We collected blood samples in 1989-1990 (Nurses' Health Study) and 1993-1995 (Health Professionals Follow-up Study). We identified 205 incident XFG cases through 2016 (average time to diagnosis from blood draw = 11.8 years) who self-reported glaucoma and were confirmed as XFG cases with medical records. We profiled plasma metabolites using liquid chromatography-mass spectrometry. We evaluated 379 known metabolites (transformed for normality using probit scores) using multiple conditional logistic models. Metabolite set enrichment analysis was used to identify metabolite classes associated with XFG. To adjust for multiple comparisons, we used number of effective tests (NEF) and the false discovery rate (FDR).

Results

Mean age of cases (n = 205) at diagnosis was 71 years; 85% were women and more than 99% were Caucasian; controls (n = 205) reported eye examinations as of the matched cases' index date. Thirty-three metabolites were nominally significantly associated with XFG (P < 0.05), and 4 metabolite classes were FDR-significantly associated. We observed positive associations for lysophosphatidylcholines (FDR = 0.02) and phosphatidylethanolamine plasmalogens (FDR = 0.004) and inverse associations for triacylglycerols (FDR < 0.0001) and steroids (FDR = 0.03). In particular, the multivariable-adjusted odds ratio with each 1 standard deviation higher plasma cortisone levels was 0.49 (95% confidence interval, 0.32-0.74; NEF = 0.05).

Conclusions

In plasma from a decade before diagnosis, lysophosphatidylcholines and phosphatidylethanolamine plasmalogens were positively associated and triacylglycerols and steroids (e.g., cortisone) were inversely associated with XFG risk.

Emerging roles of oxidative stress in the pathogenesis of pseudoexfoliation syndrome (Review)

Pseudoexfoliation syndrome (PEXS) is a systemic disease caused by defects in the extracellular matrix (ECM) remodelling process leading to the chronic deposition of extracellular, fibrillary, white flaky pseudoexfoliation material (PEXM) throughout the body. Specifically, PEXM deposits on the lens capsule cause open-angle glaucoma, cataracts and blindness in patients with PEXS. Several gene single nucleotide polymorphisms are linked to the development of PEXS in humans, including lysyl oxidase-like 1 gene, clusterin and fibulin-5. The exact reason for the PEXM generation and its resulting pathogenesis is not well understood. However, defective ECM remodelling and oxidative stress (OS) have been hypothesized as significant events leading to the PEXM. Specifically, the link between OS and PEXS has been well studied, although the investigation is still ongoing. The present review explored recent advances in various aspects of PEXS and the involvement of OS in the eye for PEXS development.

Effects of Coffee on Sirtuin-1, Homocysteine, and Cholesterol of Healthy Adults: Does the Coffee Powder Matter?

Background: Coffee is one of the most popular beverages globally and contains several bioactive compounds that are relevant to human health. Many nutritional strategies modulate sirtuin-1, thereby impacting aging and cardiometabolic health. This study investigated the influence of different blended coffees on serum sirtuin-1, blood lipids, and plasma homocysteine. Methods: An eight-week randomized clinical trial that included 53 healthy adults of both sexes analyzed the effects of daily intake of 450 to 600 mL of pure Arabica or blended (Arabica + Robusta) coffee intake of filtered coffee on blood sirtuin-1, lipids, and homocysteine. Results: Both Arabica and blended coffees similarly increased serum sirtuin-1 concentration, from 0.51 to 0.58 ng/mL (p = 0.004) and from 0.40 to 0.49 ng/mL (p = 0.003), respectively, without changing plasma homocysteine, folic acid, glucose, and CRP. However, the blended coffee intake increased total cholesterol from 4.70 to 5.17 mmol/L (p < 0.001) and LDL-cholesterol from 2.98 to 3.32 mmol/L (p < 0.001), as well as HDL-c from 1.26 to 1.36 mmol/L (p < 0.001). Conclusion: Both coffee powders increased sirtuin-1 expression, but our results suggest that blended coffee had hypercholesterolemic effects which could increase cardiovascular risk. Therefore, preference should be given to Arabica coffee for the best cardiometabolic benefits of coffee.

Impact of Coffee Consumption on Physiological Markers of Cardiovascular Risk: A Systematic Review

BACKGROUND

Coffee is one of the most widely consumed beverages globally. A substantial number of observational data suggest an inverse relationship between coffee consumption and the risk for cardiovascular disease. The basis for this association is not clear. In this review, we specifically study the impact of coffee on inflammatory biomarkers as one potential mechanistic basis for this observation. Our objective was to systematically review randomized controlled trials that examined the effects of coffee consumption on selected cardiovascular biomarkers.

METHODS

We systematically reviewed bibliographic databases including PubMed (NCBI), Embase (Elsevier), CINAHL (EBSCO), Web of Science (Clarivate Analytics), Cochrane Central Register of Controlled Trials (EBSCO), and CAB Abstracts (Clarivate Analytics). We searched for randomized controlled trials that studied the effect of drinking coffee on inflammatory markers of cardiovascular risk.

RESULTS

The search of electronic databases returned 1631 records. After removing duplicate records and ineligible studies, we examined a total of 40 full-text documents, 17 of which were eligible for further analysis. In our review, boiled coffee, in particular, appeared to raise total and low-density lipoprotein cholesterol and apolipoprotein B, but evidence suggests no similar effect for filtered coffee. One study showed a significant increase in blood interleukin 6 levels among individuals who drank caffeinated coffee, compared with individuals consuming no coffee.

CONCLUSION

Based on our systematic review of randomized controlled studies, we cannot confidently conclude that an anti-inflammatory effect of coffee is a major contributing factor to the lower all-cause mortality reported in observational studies.

A Cross-Sectional Study on the Combined Effect of Body Weight and Coffee Consumption on Serum Levels of Leptin, Vitamin B12, and Folic Acid in Healthy Young Adult Males

Purpose

Studies on the effect of body weight and coffee consumption on leptin, vitamin B12, and folic acid are scarce and conflicting. This study investigates the effect of body weight and/or coffee consumption rate on the serum levels of these molecules in healthy young adult males.

Patients and Methods

This observational cross-sectional study was carried out at the faculty of pharmacy, Applied Science Private University (ASU), Amman, Jordan, from July to September 2020. Young healthy males were invited to participate in the study and fill a questionnaire regarding lifestyle habits including coffee consumption during the last 3 months, medical history, and anthropometric measurements. Depending on BMI and extent of coffee consumption, participants were divided into 4 groups; normal body weight and moderate coffee consumption (NW/MCC) group; normal body weight and heavy coffee consumption (NW/HCC) group; overweight and moderate coffee consumption (OW/MCC) group; overweight and heavy coffee consumption (OW/HCC) group. Serum samples were taken to measure leptin, vitamin B12, and folic acid levels in addition to morning and midnight salivary cortisol and dehydroepiandrosterone (DHEA) samples.

Results

Healthy males (n = 122) aged 18 to 26 years continued participation in this study. Serum levels of leptin in NW/MCC, NW/HCC, OW/MCC, OW/HCC groups were 5.93, 5.75, 14.86, 16.79 ng/mL, respectively. Serum levels of vitamin B12 in these groups were 356.09, 402.71, 334.25, 331.05 pg/mL, respectively. While, the serum levels of folic acid were 8.92, 10.27, 10.12, 10.47 ng/mL, respectively. Body weight was positively associated with leptin (p = 0.00), negatively associated with vitamin B12 (p = 0.047), and not associated with folic acid (p = 0.235). Coffee consumption rate had no significant effect on leptin, vitamin B12, or folic acid. Finally, the combination of body weight and coffee consumption had no significant effect on leptin, vitamin B12, or folic acid.

Conclusion

There was no possible synergistic effect between body weight and coffee consumption rate on leptin, vitamin B12, or folic acid levels. However, overweight was associated with higher leptin, lower vitamin B12, and no change in folic acid levels.

Trial Registration

This trial was registered at clinicaltrials.gov as NCT04488731.

Effect of coffee consumption on dyslipidemia: A meta-analysis of randomized controlled trials

BACKGROUND AND AIM

Dyslipidemia is a common metabolic disease worldwide and also an important predisposing factor for cardiovascular diseases (CVDs). Coffee is loved by people all over the world; however, the association between coffee consumption and blood lipids has yielded inconsistent results. So we carried this meta-analysis to explore the effects of coffee consumption on blood lipids.

METHODS AND RESULTS

Medline, PubMed, Web of science, Embase, and Cochrane Library databases were systematically searched until April 2020. Combined weighted mean differences (WMD) with their 95% confidence interval (CI) were calculated using random-effects models, and between-study heterogeneity was assessed by Cochran's Q test and I² statistics. Subgroup analysis and meta-regression analysis were also conducted to explore the potential heterogeneity. A total of 12 RCT studies involving the association between coffee consumption and blood lipid levels were included in the meta-analysis. The pooled results showed that coffee consumption significantly increased total cholesterol (TC) (WMD: 0.21 mmol/L, 95% CI: 0.04; 0.39, P = 0.017), triglyceride (TG) (WMD: 0.12 mmol/L, 95% CI: 0.03; 0.20, P = 0.006) and low-density lipoprotein (LDL-C) (WMD: 0.14 mmol/L, 95% CI: 0.05; 0.24, P = 0.003) while had no significant effect on high-density lipoprotein (HDL-C) (WMD: -0.01 mmol/L, 95% CI: -0.06; 0.04, P = 0.707). Dose-response analysis results revealed significant positive nonlinear associations between coffee consumption and the increase in TC, LDL-C, and TG levels.

CONCLUSIONS

Evidence from this meta-analysis suggested that coffee consumption may be associated with an elevated risk for dyslipidemia and CVDs. So a reasonable habit of coffee consumption (<3 cups/d) is essential for the prevention of dyslipidemia.

The gut microbiome drives inter- and intra-individual differences in metabolism of bioactive small molecules

The origin of inter-individual variability in the action of bioactive small molecules from the diet is poorly understood and poses a substantial obstacle to harnessing their potential for attenuating disease risk. Epidemiological studies show that coffee lowers the risk of developing type 2 diabetes, independently of caffeine, but since coffee is a complex matrix, consumption gives rise to different classes of metabolites in vivo which in turn can affect multiple related pathways in disease development. We quantified key urinary coffee phenolic acid metabolites repeated three times in 36 volunteers, and observed the highest inter- and intra-individual variation for metabolites produced by the colonic microbiome. Notably, a urinary phenolic metabolite not requiring the action of the microbiota was positively correlated with fasting plasma insulin. These data highlight the role of the gut microbiota as the main driver of both intra- and inter-individual variation in metabolism of dietary bioactive small molecules.

Lysyl Oxidase Like 1: Biological roles and regulation

Lysyl Oxidase Like 1 (LOXL1) is a gene that encodes for the LOXL1 enzyme. This enzyme is required for elastin biogenesis and collagen cross-linking, polymerising tropoelastin monomers into elastin polymers. Its main role is in elastin homeostasis and matrix remodelling during injury, fibrosis and cancer development. Because of its vast range of biological functions, abnormalities in LOXL1 underlie many disease processes. Decreased LOXL1 expression is observed in disorders of elastin such as Cutis Laxa and increased expression is reported in fibrotic disease such as Idiopathic Pulmonary Fibrosis. LOXL1 is also downregulated in the lamina cribrosa in pseudoexfoliation glaucoma and genetic variants in the LOXL1 gene have been linked with an increased risk of developing pseudoexfoliation glaucoma and pseudoexfoliation syndrome. However the two major risk alleles are reversed in certain ethnic groups and are present in a large proportion of the normal population, implying complex genetic and environmental regulation is involved in disease pathogenesis. It also appears that the non-coding variants in intron 1 of LOXL1 may be involved in the regulation of LOXL1 expression. Gene alteration may occur via a number of epigenetic and post translational mechanisms such as DNA methylation, long non-coding RNAs and microRNAs. These may represent future therapeutic targets for disease. Environmental factors such as hypoxia, oxidative stress and ultraviolet radiation exposure alter LOXL1 expression, and it is likely a combination of these genetic and environmental factors that influence disease development and progression. In this review, we discuss LOXL1 properties, biological roles and regulation in detail with a focus on pseudoexfoliation syndrome and glaucoma.

Combined Effect Of Coffee Consumption And Cigarette Smoking On Serum Levels Of Vitamin B12, Folic Acid, And Lipid Profile In Young Male: A Cross-Sectional Study

OBJECTIVE

To investigate the associations of coffee consumption and/or smoking on certain clinical outcomes including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), vitamin B12, and folic acid in a population of young healthy men.

METHOD

This cross-sectional study was conducted in Amman, Jordan, over 4 months. Participants were approached for study participation and asked to fill a questionnaire about their anthropometric information, habitual smoking, and coffee consumption during the last 3 months. Their fasting blood samples were taken to measure TC and LDL-C.

RESULTS

Healthy male participants (n=117) in the age range of 18 to 26 years were recruited. Mean serum TC was higher in heavy coffee consumers (C++) group (≥3 cups/day) with or without smoking (M= 179.9±34.59 mg/dL and 195.94±23.69 mg/dL) in comparison with moderate coffee consumers (C+) group (1-2 cups/day) (M= 158.1±24.82 mg/dL and 177.23±34.17 mg/dL), and the mean level was higher in subjects who were coffee consumers only than smokers who were coffee consumers. LDL-C levels were higher in participants who were coffee consumers (M= 103.06±34.82mg/dL and 118.06±19.31 mg/dL) than smokers who were coffee consumers (M= 88.6±22.40 mg/dL and 108.26±37.57 mg/dL). No significant difference was noted regarding HDL-C, vitamin B12, and folic acid.

CONCLUSION

Our findings showed that heavy coffee consumption was more associated with hyperlipidemia than cigarette smoking. Accordingly, we conclude that moderate coffee consumption may reduce the risk of cardiovascular diseases or their consequences in male.

The Cigarette Smoking, Coffee and Supplements Intake at Students of Sarajevo University

Introduction:

The dietary supplements are defined as vitamins and minerals or herbal products and are typically given in the form of a capsule or tablet. The nonsmokers are more attempted to use dietary supplements than individuals who smoke.

Aim:

In our investigation, we examined associations between vitamin B, folic acid, multivitamin or mineral intake among the student population and their correlation with smoking prevalence and drinking coffee.

Materials and methods:

We used a questionnaire to examine the general characteristics of the subjects, age, sex, their lifestyle, cigarette smoking, coffee intake and their use of dietary supplements. Data were collected from participants of the University of Sarajevo and a longitudinal study of 960 men and women aged 18-24 years from 2017 to 2018 was conducted.

Results:

The results showed that 32% of students took vitamin B supplements and 10% folic acid. In opposite, more than half of students took multivitamins (59.5%) and minerals (60.4%) less than one year. About a quarter or less took multivitamins (23.9%) and minerals (24.3%) for years. Less than 20% of students took multivitamins and minerals within a period of one year. In student population smoking prevalence was estimated at 21.2% and coffee intake in 71.2%. The smoking and use of vitamin B supplements were independent of each other, p = 0.201. The use of folic acid did not depend on smoking p = 0.501. There were no observed correlations between multivitamin and mineral supplement consumption compared to smoking status or drinking coffee.

Conclusion:

Deficient dietary intake of folic acid and B vitamins from food and supplemental sources appear to be one of the atherosclerosis incidences. Further studies should examine associations between dietary supplements intake and lifestyle of students, as well as smoking status and coffee intake.

Potential nutraceutical and food additive properties and risks of coffee: a comprehensive overview

Coffee is a composite mixture of more than a thousand diverse phytochemicals like alkaloids, phenolic compounds, vitamins, carbohydrates, lipids, minerals and nitrogenous compounds. Coffee has multifunctional properties as a food additive and nutraceutical. As a nutraceutical, coffee has anti-inflammatory, anti-oxidant, antidyslipidemic, anti-obesity, type-2 diabetes mellitus (DM), and cardiovascular diseases (CVD), which can serve for the treatment and prevention of metabolic syndrome and associated disorders. On the other hand, as a food additive, coffee has antimicrobial activity against a wide range of microorganisms, inhibits lipid peroxidation (LPO), and can function as a prebiotic. The outcomes of different studies also revealed that coffee intake may reduce the incidence of numerous chronic diseases, like liver disease, mental health, and it also overcomes the all-cause mortality, and suicidal risks. In some studies, high intake of coffee is linked to increase CVD risk factors, like cholesterol, plasma homocysteine and blood pressure (BP). There is also a little evidence that associated the coffee consumption with increased risk of lung tumors in smokers. Among adults who consume the moderate amount of coffee, there is slight indication of health hazards with strong indicators of health benefits. Moreover, existing literature suggests that it may be cautious for pregnant women to eliminate the chances of miscarriages and impaired fetal growth. The primary purpose of this narrative review is to provide an overview of the findings of the positive impacts and risks of coffee consumption on human health. In conclusion, to date, the best available evidence from research indicates that drinking coffee up to 3-4 cups/day provides health benefits for most people.

Diet and Lifestyle Role in Homocysteine Metabolism in Turner Syndrome

OBJECTIVE

Patients with Turner syndrome (TS) have an unfavorable cardiometabolic profile. Hyperhomocysteinemia is a potential cardiovascular risk factor influenced by genetic and environmental factors, therapies, unbalanced diets and other lifestyle factors. We retrospectively studied the relationship between total plasma homocysteine (Hcy), serum vitamin B12 (B12) and folate concentration in TS patients, taking into account the genetic profile, diet, smoking habits, hormonal therapies and dietary supplements of the subjects.

PATIENTS AND METHODS

We evaluated 50 TS patients (31.5 ± 12.5 years). Medication, including vitamin supplementation, was obtained. Eating habits, cigarette smoking, alcohol and coffee consumption were investigated using phone interviews. Levels of Hcy metabolism parameters were classified by using the relevant cutoff value for an adult population and compared with a reference sample drawn from the general population.

RESULTS

Inadequate Hcy and B12 levels were noted, despite vitamin supplementation. Holotranscobalamin (HoloTC) was above the relevant cutoff in the population, and supplemented subjects showed mean levels lower than nonsupplemented subjects (p = 0.005). Dietary supplementation (p = 0.038), lifestyle (coffee consumption, p = 0.01) and hormonal replacement therapy (p = 0.02) are important factors for Hcy metabolism. No genetic influence on Hcy levels was noted. Multivariable regression analysis identified vitamin supplementation (p = 0.045) as the only independent predictor of increased Hcy levels.

CONCLUSION

Cardiovascular risk in TS can be reduced using educational approaches to a healthy lifestyle with dietary guidelines. Besides this, we also recommend measuring HoloTC for the prompt detection of B12 deficiency and to consider hormone replacement therapy in the biochemical assessment of homocysteine in TS.

The associations between smoking, physical activity, dietary habits and plasma homocysteine levels in cardiovascular disease-free people: the ‘ATTICA’ study

Homocysteine levels are considered, by some investigators, as an independent factor of cardiovascular disease; however, others suggest that there is not a causal relationship. The aim of this work was to investigate the associations between homocysteine levels and several lifestyle-related factors. The ATTICA study is a population-based cohort that has randomly enrolled 1128 adult men and 1154 women, stratified by age and gender, from the greater area of Athens, during 2001 2002. Among several demographic, lifestyle, clinical and biochemical characteristics, we measured total plasma homocysteine levels. For the present analysis, we excluded people who had a history of cardiovascular disease. The factors that showed the strongest relationship with homocysteine levels, in both genders, even after adjusting for several potential confounders were: cigarette smoking (p=0.03), endurance exercise (inverse, p<0.05), fruit (inverse, p=0.01) and vegetable intake (inverse, p=0.04), and alcohol (p=0.04) and coffee intake (p=0.04). In conclusion, several lifestyle-related factors seem to be associated with homocysteine levels. However, the vast majority of the associations were weak when we adjusted for other co-factors. The latter may indicate the mutual confounding effect of various socio-demographic, anthropometric and other clinical characteristics on the relationship between homocysteine and cardiovascular risk.

Caffeine-Withdrawal Headache. The Vågå Study of Headache Epidemiology

In connection with the Vågå study of headache epidemiology, a search was made for caffeine-withdrawal headache in 1741 parishioners. Female to male ratio 1.05; mean age 44.2 years (range 18-65 years). A face-to-face interview technique was used. The mean consumption of coffee was 4.7 cups a day. Males on an average consumed more coffee (5.1 ± 3.3 cups/day) than females (4.4 ± 3.1 cups/day). Neither in those with a high consumption of coffee: ≥10 cups a day ( n = 134), nor in those with a considerable variation in consumption: ≥10 cups/day ( n = 31) did there seem to be a definite increase in headache resembling caffeine-withdrawal headache, for instance during weekends. In seven parishioners, however, there did seem to be such a headache, and in two of them, the evidence was rather convincing. This headache generally seemed to be mild and global and occurred mainly in the morning hours on weekends. There was no nausea, no throbbing quality of the pain, and no reported use of analgesics. Coffee seemed to abate the headache. This frequency (0.4%) should, clearly, be regarded as a minimum figure. Caffeine-withdrawal headache at the grassroots level may be a rather rare, generally vague, symptom-poor headache.

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.

Direct and Functional Biomarkers of Vitamin B6 Status

Measures of B6 status are categorized as direct biomarkers and as functional biomarkers. Direct biomarkers measure B6 vitamers in plasma/serum, urine and erythrocytes, and among these plasma pyridoxal 5'-phosphate (PLP) is most commonly used. Functional biomarkers include erythrocyte transaminase activities and, more recently, plasma levels of metabolites involved in PLP-dependent reactions, such as the kynurenine pathway, one-carbon metabolism, transsulfuration (cystathionine), and glycine decarboxylation (serine and glycine). Vitamin B6 status is best assessed by using a combination of biomarkers because of the influence of potential confounders, such as inflammation, alkaline phosphatase activity, low serum albumin, renal function, and inorganic phosphate. Ratios between substrate-products pairs have recently been investigated as a strategy to attenuate such influence. These efforts have provided promising new markers such as the PAr index, the 3-hydroxykynurenine:xanthurenic acid ratio, and the oxoglutarate:glutamate ratio. Targeted metabolic profiling or untargeted metabolomics based on mass spectrometry allow the simultaneous quantification of a large number of metabolites, which are currently evaluated as functional biomarkers, using data reduction statistics.

Oxidative stress in dry age-related macular degeneration and exfoliation syndrome

Oxidative stress refers to cellular or molecular damage caused by reactive oxygen species, which especially occurs in age-related conditions as a result of an imbalance between the production of reactive oxygen species and the antioxidant defense response. Dry age-related macular degeneration (AMD) and exfoliation syndrome (XFS) are two common and complex age-related conditions that can cause irreversible vision loss. Two subtypes of AMD, which is the leading cause of blindness in the Western world, exist: the most prevalent dry type and the most severe wet type. Early dry AMD is characterized by formation of drusen, which are sub-retinal deposits, in the macular area and may progress to geographic atrophy with more dramatic manifestation. XFS is a systemic disorder of the extracellular matrix characterized by the accumulation of elastic fibrils that leads, in most cases, to glaucoma development with progressive and irreversible vision loss. Due to the aging population, the prevalence of these already-widespread conditions is increasing and is resulting in significant economic and psychological costs for individuals and for society. The exact composition of the abnormal drusen and XFS material as well as the mechanisms responsible for their production and accumulation still remain elusive, and consequently treatment for both diseases is lacking. However, recent epidemiologic, genetic and molecular studies support a major role for oxidative stress in both dry AMD and XFS development. Understanding the early molecular events in their pathogenesis and the exact role of oxidative stress may provide novel opportunities for therapeutic intervention for the prevention of progression to advanced disease.

The Relationship between caffeine and coffee consumption and exfoliation glaucoma or glaucoma suspect: a prospective study in two cohorts

PURPOSE

We examined the association between caffeine and caffeinated beverage consumption in relation to the risk of exfoliation glaucoma or exfoliation glaucoma suspect (EG/EGS).

METHODS

We followed 78,977 women from the Nurses' Health Study (NHS) and 41,202 men from the Health Professionals Follow-up Study (HPFS) who were at least 40 years of age, did not have glaucoma, and reported undergoing eye examinations from 1980 (NHS) or 1986 (HPFS) to 2008. Information on consumption of caffeine-containing beverages and potential confounders were repeatedly ascertained in validated follow-up questionnaires. Confirmation with medical record review revealed 360 incident EG/EGS cases. Multivariate rate ratios (RRs) for EG/EGS were calculated in each cohort and then pooled using meta-analytic techniques.

RESULTS

Compared with participants whose cumulatively updated total caffeine consumption was <125 mg/day, participants who consumed ≥ 500 mg/day had a trend toward increased risk of EG/EGS that was not statistically significant (RR = 1.43; 95% confidence interval [CI], 0.98-2.08); P trend = 0.06). Compared to abstainers, those who drank ≥ 3 cups of caffeinated coffee daily were at increased risk of EG/EGS (RR = 1.66; 95% CI, 1.09-2.54; P trend = 0.02). These results were not materially altered after adjustment for total fluid intake. Associations were stronger among women with a family history of glaucoma (P interaction = 0.06 for coffee; P interaction = 0.03 for caffeine). We did not find associations with consumption of other caffeinated products (caffeinated soda, caffeinated tea, decaffeinated coffee or chocolate) and risk of EG/EGS (P trend ≥ 0.31).

CONCLUSIONS

We observed a positive association between heavier coffee consumption with risk of EG/EGS in this large prospective study.

Functional foods and nutraceuticals in the primary prevention of cardiovascular diseases

Cardiovascular disease (CVD) is now the leading cause of death globally and is a growing health concern. Dietary factors are important in the pathogenesis of CVD and may to a large degree determine CVD risk, but have been less extensively investigated. Functional foods are those that are thought to have physiological benefits and/or reduce the risk of chronic disease beyond their basic nutritional functions. The food industry has started to market products labelled as “functional foods.” Although many review articles have focused on individual dietary variables as determinants of CVD that can be modified to reduce the risk of CVD, the aim of this current paper was to examine the impact of functional foods in relation to the development and progression of CVD. Epidemiologic studies have demonstrated the association between certain dietary patterns and cardiovascular health. Research into the cardio-protective potential of their dietary components might support the development of functional foods and nutraceuticals. This paper will also compare the effect of individual bioactive dietary compounds with the effect of some dietary patterns in terms of their cardiovascular protection.

Consumo de café segundo métodos de preparo da bebida e associação com perfil lipídico sérico em hipertensos e diabéticos

OBJETIVO: Verificar o consumo da bebida café segundo a quantidade ingerida e os métodos de preparo, e sua associação com o perfil lipídico sérico de hipertensos e diabéticos. MÉTODOS: Foram coletados, por meio de entrevista, dados demográficos, de estilo de vida e de consumo alimentar, aferidas medidas antropométricas e colhido sangue para análise de perfil lipídico sérico. Análise descritiva, testes t de Student, qui-quadrado e de correlação linear de Pearson foram utilizados com 5% de probabilidade de erro experimental. RESULTADOS: Foram avaliados 182 indivíduos hipertensos e diabéticos tipo 2, consumidores de café, distribuídos em dois grupos segundo o método de preparo da bebida: à brasileira e fervido. Os grupos foram semelhantes quanto aos dados demográficos, antropométricos, de estilo de vida, de consumo alimentar e de perfil lipídico sérico. A quantidade per capita de pó utilizado no método à brasileira e no fervido foi de M=7,52, DP=4,99g e M=7,91, DP=5,87g, respectivamente. O volume ingerido e a frequência de consumo dos indivíduos do grupo à brasileira foi de M=517,3, DP=402,7mL e M=2,14, DP=1,06 vezes/dia, e para os consumidores de café fervido, M=513,4, DP=409,8mL e M=2,2, DP=0,94 vezes/dia. Não houve associação significativa entre a quantidade ingerida da bebida café e o perfil lipídico sérico. CONCLUSÃO: Não houve associação entre o consumo de café à brasileira ou fervido e o perfil lipídico sérico, possivelmente em função da quantidade consumida e/ou da diluição utilizada. Se, por um lado, os resultados não permitem desestimular o consumo da bebida na quantidade ingerida pela população estudada, como medida de prevenção cardiovascular, por outro lado autorizam concluir que há necessidade de avançar nessa linha de investigação.

The cardiovascular effects of methylxanthines

In the concentration range that is normally achieved in humans, e.g., after the drinking of coffee or in patients treated with theophylline, the cardiovascular effects of methylxanthines are primarily due to antagonism of adenosine A(1) and A(2) receptors. Inhibition of phosphodiesterases or mobilization of intracellular calcium requires much higher concentrations. In conscious humans, acute exposure to caffeine results in an increase in blood pressure by an increased total peripheral resistance, and a slight decrease in heart rate. This overall hemodynamic response is composed of direct effects of caffeine on vascular tone, on myocardial contractility and conduction, and on the sympathetic nervous system. Caffeine is the most widely consumed methylxanthine, mainly derived from coffee intake. Regular coffee consumption can affect various traditional cardiovascular risk factors, including a slight increase in blood pressure, an increase in plasma cholesterol and homocysteine levels, and a reduced incidence of type 2 diabetes mellitus. Although most prospective studies have not reported an association between coffee consumption and coronary heart disease, these findings do not exclude that the acute hemodynamic and neurohumoral effects of coffee consumption could have an adverse effect in selected patient groups who are more vulnerable for these effects, based on their genetic profile or medication use.

Variation in the human lipidome associated with coffee consumption as revealed by quantitative targeted metabolomics

The effect of coffee consumption on human health is still discussed controversially. Here, we report results from a metabolomics study of coffee consumption, where we measured 363 metabolites in blood serum of 284 male participants of the Cooperative Health Research in the Region of Augsburg study population, aged between 55 and 79 years. A statistical analysis of the association of metabolite concentrations and the number of cups of coffee consumed per day showed that coffee intake is positively associated with two classes of sphingomyelins, one containing a hydroxy-group (SM(OH)) and the other having an additional carboxy-group (SM(OH,COOH)). In contrast, long- and medium-chain acylcarnitines were found to decrease with increasing coffee consumption. It is noteworthy that the concentration of total cholesterol also rises with an increased coffee intake in this study group. The association observed here between these hydroxylated and carboxylated sphingolipid species and coffee intake may be induced by changes in the cholesterol levels. Alternatively, these molecules may act as scavengers of oxidative species, which decrease with higher coffee intake. In summary, we demonstrate strong positive associations between coffee consumption and two classes of sphingomyelins and a negative association between coffee consumption and long- and medium-chain acylcarnitines.

Functional foods for dyslipidaemia and cardiovascular risk prevention

A food can be regarded as ‘functional’ if it can demonstrate a beneficial efficacy on one or more target functions in the body in a convincing way. Beyond adequate nutritional qualities, functional foods should either improve the state of health and wellbeing and/or reduce the risk of disease. Functional foods that are marketed with claims of heart disease reduction focus primarily on the major risk factors, i.e. cholesterol, diabetes and hypertension. Some of the most innovative products are designed to be enriched with ‘protective’ ingredients, believed to reduce risk. They may contain, for example, soluble fibre (from oat and psyllium), useful both for lowering cholesterol and blood pressure, or fructans, effective in diabetes. Phytosterols and stanols lower LDL-cholesterol in a dose-dependent manner. Soya protein is more hypocholesterolaemic in subjects with very high initial cholesterol and recent data indicate also favourable activities in the metabolic syndrome.n-3 Fatty acids appear to exert significant hypotriacylglycerolaemic effects, possibly partly responsible for their preventive activity. Dark chocolate is gaining much attention for its multifunctional activities, useful both for the prevention of dyslipidaemia as well as hypertension. Finally, consensus opinions about tea and coffee have not emerged yet, and the benefits of vitamin E, garlic, fenugreek and policosanols in the management of dyslipidaemia and prevention of arterial disease are still controversial.

Lifestyle and genetic determinants of folate and vitamin B12 levels in a general adult population

Danish legislation regarding food fortification has been very restrictive resulting in few fortified food items on the Danish market. Folate and vitamin B12 deficiency is thought to be common due to inadequate intakes but little is known about the actual prevalence of low serum folate and vitamin B12 in the general population. The aim of the present study was to evaluate the folate and vitamin B12 status of Danish adults and to investigate associations between vitamin status and distinct lifestyle and genetic factors. The study included a random sample of 6784 individuals aged 30–60 years. Information on lifestyle factors was obtained by questionnaires and blood samples were analysed for serum folate and vitamin B12 concentrations and several genetic polymorphisms. The overall prevalence of low serum folate ( < 6·8 nmol/l) was 31·4 %. Low serum folate was more common among men than women and the prevalence was lower with increasing age. Low serum folate was associated with smoking, low alcohol intake, high coffee intake, unhealthy diet, and the TT genotype of the methylenetetrahydrofolate reductase (MTHFR)-C677T polymorphism. The overall prevalence of low serum vitamin B12 ( < 148 pmol/l) was 4·7 %. Low serum vitamin B12 was significantly associated with female sex, high coffee intake, low folate status, and the TT genotype of the MTHFR-C677T polymorphism. In conclusion, low serum folate was present in almost a third of the adult population in the present study and was associated with several lifestyle factors whereas low serum concentrations of vitamin B12 were less common and only found to be associated with a few lifestyle factors.

Coffee consumption and circulating B-vitamins in healthy middle-aged men and women

BACKGROUND

Coffee consumption has been associated with several risk factors for coronary heart disease, including increased cholesterol, increased blood pressure, and increased plasma total homocysteine (tHcy). tHcy is determined by several B-vitamins. However, reports about the association between coffee intake and B-vitamin status are few.

METHODS

We measured plasma B-vitamins and tHcy in a cohort of 10,601 healthy, middle-aged Norwegian men and women. Information about lifestyle factors, including coffee consumption, smoking, alcohol use, height, and weight, was obtained by interview.

RESULTS

Coffee consumption was dose-dependently associated with reduced plasma B-vitamin concentrations. Compared with coffee abstainers, individuals drinking >or=4 cups/day had 11.7% (P < 0.001), 14.1% (P < 0.001), and 5.5% (P = 0.01) lower plasma concentrations of folate, pyridoxal phosphate, and riboflavin, respectively, and the mean tHcy concentration was 6.8% (P < 0.001) higher. Quantile regression analysis showed essentially no difference in B-vitamin concentrations between coffee consumption categories at low vitamin concentrations but a progressive increase in the difference at higher concentrations. This pattern of differences (effect profile) was found independently of smoking status, alcohol intake, and sex. The decrease in folate explained approximately half of the increase in tHcy.

CONCLUSIONS

Coffee consumption was associated with reduced circulating B-vitamin concentrations. The observed effect profiles indicated that coffee consumption preferentially affected the upper, but not the lower, part of the B-vitamin concentration distributions. We hypothesize that coffee consumption may increase the loss of surplus B-vitamins by excretion in urine.

Coffee consumption and risk of type 2 diabetes and heart disease

Coffee seems to have distinct acute and long-term effects on health, which can be modified by genetic background. Coffee consumption is potentially protective against the development of type 2 diabetes, but given the lack of a solid biological basis for this association, and the possible adverse cardiovascular effects of coffee, recommendations for optimal coffee intake are difficult to establish.

Induced changes in the consumption of coffee alter ad libitum dietary intake and physical activity level

Dietary trials with subjects on a freely selected diet may be affected by unwanted behavioural changes. Few studies, if any, have examined changes in coffee consumption and possible concomitant changes in diet and health-related habits. The aim of the present study was to examine whether induced changes in coffee consumption lead to changes in food habits and leisure-time physical activity. Healthy, non-smoking coffee-drinkers (n 214) were asked to change their coffee habits in a controlled clinical trial on the metabolic effects of coffee. The participants were asked to maintain their usual dietary habits. Self-perceived changes in diet and physical activity during the 6-week intervention period were assessed at the end. In the analyses, the participants were rearranged into groups reflecting the difference in coffee intake during the trial as compared with habitual intake. Associations with changes in food intake or physical activity were analysed by Spearman rank correlation. Changes in intake of ‘chocolate, sweets’ (r 0·179, P<0·05), ‘cakes, sweet biscuits, pastry’ (r 0·306, P<0·001), and ‘jam’ (r 0·198, P<0·05) showed positive associations with change in coffee intake during the trial. Negative associations were found for ‘dishes with fish’ (r -0·204, P<0·01) and many of the drinks as well as with physical activity (r -0·164, P<0·05). Induced changes in coffee intake seem to alter ad libitum intake of several foods. The recognized associations between health behaviours may have physiological explanations.

Coffee, diabetes, and weight control

Several prospective epidemiologic studies over the past 4 y concluded that ingestion of caffeinated and decaffeinated coffee can reduce the risk of diabetes. This finding is at odds with the results of trials in humans showing that glucose tolerance is reduced shortly after ingestion of caffeine or caffeinated coffee and suggesting that coffee consumption could increase the risk of diabetes. This review discusses epidemiologic and laboratory studies of the effects of coffee and its constituents, with a focus on diabetes risk. Weight loss may be an explanatory factor, because one prospective epidemiologic study found that consumption of coffee was followed by lower diabetes risk but only in participants who had lost weight. A second such study found that both caffeine and coffee intakes were modestly and inversely associated with weight gain. It is possible that caffeine and other constituents of coffee, such as chlorogenic acid and quinides, are involved in causing weight loss. Caffeine and caffeinated coffee have been shown to acutely increase blood pressure and thereby to pose a health threat to persons with cardiovascular disease risk. One short-term study found that ground decaffeinated coffee did not increase blood pressure. Decaffeinated coffee, therefore, may be the type of coffee that can safely help persons decrease diabetes risk. However, the ability of decaffeinated coffee to achieve these effects is based on a limited number of studies, and the underlying biological mechanisms have yet to be elucidated.

Coffee and health: a review of recent human research

Coffee is a complex mixture of chemicals that provides significant amounts of chlorogenic acid and caffeine. Unfiltered coffee is a significant source of cafestol and kahweol, which are diterpenes that have been implicated in the cholesterol-raising effects of coffee. The results of epidemiological research suggest that coffee consumption may help prevent several chronic diseases, including type 2 diabetes mellitus, Parkinson's disease and liver disease (cirrhosis and hepatocellular carcinoma). Most prospective cohort studies have not found coffee consumption to be associated with significantly increased cardiovascular disease risk. However, coffee consumption is associated with increases in several cardiovascular disease risk factors, including blood pressure and plasma homocysteine. At present, there is little evidence that coffee consumption increases the risk of cancer. For adults consuming moderate amounts of coffee (3-4 cups/d providing 300-400 mg/d of caffeine), there is little evidence of health risks and some evidence of health benefits. However, some groups, including people with hypertension, children, adolescents, and the elderly, may be more vulnerable to the adverse effects of caffeine. In addition, currently available evidence suggests that it may be prudent for pregnant women to limit coffee consumption to 3 cups/d providing no more than 300 mg/d of caffeine to exclude any increased probability of spontaneous abortion or impaired fetal growth.

Boiled or Filtered Coffee?

Caffeine is the most widely consumed psychostimulant drug in the world that mostly is consumed in the form of coffee. Whether caffeine and/or coffee consumption contribute to the development of cardiovascular disease (CVD), the single leading cause of death in the US, is unclear.This article examines the effects of caffeine intake, both alone and via coffee consumption, on key blood markers of CVD risk: lipoproteins (cholesterol, triglycerides), fibrinogen (a biomarker of blood clotting) and C-reactive protein (CRP; a biomarker of inflammation). These blood markers and their role in the development of CVD are reviewed first. Studies examining caffeine and coffee effects on each of these blood markers are then presented. Next, biobehavioural moderators of the relationship between caffeine and/or coffee consumption and CVD are discussed, including genetics, sex and tobacco smoking. The literature indicates a strong relationship between boiled, unfiltered coffee consumption and elevated cholesterol levels; however, there is a critical gap in the literature regarding the effects of coffee or caffeine consumption on fibrinogen or CRP, which is an independent predictor of CVD risk. Available studies are limited by small samples sizes, inclusion of only men (or few women) and unrepresented age or ethnic groups. Thiere is a critical need for controlled laboratory and epidemiological studies that include fibrinogen and CRP markers of CVD risk before conclusions can be drawn regarding the health effects of caffeine and/or coffee in a normal, healthy population of men and women.

Association of serum caffeine concentrations with blood lipids in caffeine-drug users and nonusers - results of German National Health Surveys from 1984 to 1999

Previous studies regarding effects of caffeine on lipids focused mainly on coffee consumption, the real association of serum caffeine concentrations with blood lipids is unclear. 814 caffeine-drug users who had taken any caffeine/caffeine-containing pharmaceutical products and 623 nonusers without any drug use in the last seven days before the medical interview were identified from German National Health Surveys from 1984 to 1999. Serum caffeine concentrations were measured by using EIA for caffeine-drug users and nonusers in the same laboratory. Blood lipids were measured routinely for all survey participants. The association of caffeine concentrations with blood lipids was established by means of partial correlation analysis and regression analysis. After controlling for influence factors, caffeine concentrations were closely positively related to triglycerides in caffeine-drug users (male: r = 0.245, p < 0.001; female: r = 0.117, p = 0.018) and related to HDL-C in female nonusers (r = 0.245, p < 0.001). No associations were found between caffeine concentrations and total cholesterol and LDL-C levels in any groups of our study. Acute intake of caffeine might increase triglycerides levels especially in men while chronic intake of caffeine might be weakly but positively associated with HDL-C concentrations in women. The effects of caffeine on the pathogenesis of cardiovascular diseases should be further confirmed through epidemiological studies.

The association between lifestyle-related factors and plasma homocysteine levels in healthy individuals from the "ATTICA" Study

OBJECTIVE

The aim of this work was to investigate the associations between homocysteine levels and several lifestyle-related factors, in a population-based sample of Greek adults.

METHODS

During 2001-2002, we randomly enrolled 1128 men and 1154 women, from Athens area. The sampling was stratified by the age-gender distribution of the underlying population. Among several demographic, lifestyle, clinical and biochemical factors, we measured plasma total homocysteine levels. For the present analysis, we excluded people who had a history of cardiovascular disease.

RESULTS

Homocysteine values were higher in men as compared to women (14.5+/-6 vs. 10.8+/-3.5 micromol/l, p<0.001). Twenty-five percent of men and 15% of women had plasma homocysteine levels >14 micromol/l. Postmenopausal women had higher homocysteine levels (12.0+/-5.2 vs. 9.9+/-2.9 micromol/l, p<0.001). The lifestyle factors most strongly associated with plasma total homocysteine were number of cigarettes smoked (r=0.12, p=0.004), fruits (r=-0.12, p=0.006) and vegetables consumption (r=-0.15, p=0.02), alcohol (r=0.11, p=0.04) and coffee drinking (r=0.10, p=0.03). Additionally, aerobic exercise was related with lower homocysteine levels as compared to anaerobic or sedentary life (11.0+/-2.6 vs. 12.4+/-2.5 vs. 12.5+/-2.3 micromol/l, respectively, p=0.04). Multivariate analysis after adjusting for several potential confounders confirmed the previous associations. No relationship was observed of homocysteine with the Mediterranean diet score (r=0.02, p=0.85).

CONCLUSIONS

Several lifestyle-related factors were associated with homocysteine levels. Identifying and understanding modifiable factors related to homocysteine, a possible risk factor for vascular disease, might be especially important for the public health.

Plasma homocysteine, vitamin B12 and folate in Alzheimer's patients and healthy Arabs in Israel

High plasma homocysteine (tHcy) is a risk factor for cardiovascular disease and stroke and Alzheimer's disease (AD). An inverse relationship has been reported between tHcy and plasma B12 and folate levels. Seventy-nine AD patients and 156 controls from three Arab villages in northern Israel participated. Plasma tHcy, B12 and folate levels were determined. Data were analyzed using univariate statistical tests and logistical regression with confounders. tHcy was significantly higher in AD patients (20.6+/-8.7 micromol/l) than in controls (16.4+/-6.5 micromol/l) (p=0.03) after correction for year of birth, gender and smoking status. Plasma B12 (322.9+/-136.0/350.5+/-175.3 pmol/l) and plasma folate (4.5+/-3.8/4.9+/-2.6 nmol/l) levels did not differ significantly between AD patients and controls. Subjects in the highest tHcy tertile or in the lowest B12 and folate tertiles did not have greater risk to develop AD. In this population residing in Arab villages in northern Israel, tHcy levels were significantly higher among AD patients than in controls. Plasma B12 and folate levels were lower among cases but were not significant. There was not a significant association between plasma tHcy, B12 and folate levels in controls or AD patients. High levels of tHcy may suggest the need for folate and vitamin B12 supplementation in this population.

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) ε2/ε3/ε4 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 ε2 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 ε 2 allele is associated with lower serum cholesterol concentration. However, the APOE polymorphism does not seem to influence the cholesterol-raising effect of coffee.

Changes in lifestyle and plasma total homocysteine: the Hordaland Homocysteine Study

BACKGROUND

Elevated plasma concentrations of total homocysteine (tHcy) are a risk factor for cardiovascular disease. tHcy is a marker of folate and cobalamin deficiencies and is also related to several lifestyle factors.

OBJECTIVE

We examined whether changes in lifestyle influence tHcy over time.

DESIGN

A population-based, prospective study was conducted in 7031 subjects from western Norway who constituted 2 age groups (41-42 and 65-67 y) at baseline (1992-1993). The subjects were reinvestigated in 1997-1999 ( follow-up: 6 y).

RESULTS

During follow-up, median tHcy concentrations decreased 0.10 (25th and 75th percentiles: -1.24, 1.00) micromol/L in the younger subjects and increased 0.39 (25th and 75th percentiles: -0.99, 1.79) micromol/L in the older subjects. Changes in plasma vitamin status and vitamin supplement use were the strongest determinants of changes in tHcy over time. Each unit increase in plasma folate (nmol/L) and vitamin B-12 (pmol/L) was associated with reductions in tHcy concentrations of 0.2 and 0.1 micromol/L, respectively. Among the younger and older age groups, those who started to take vitamin supplements during follow-up had significant reductions in tHcy concentrations of 0.42 (95% CI: -0.65, -0.20) and 0.41 (-0.78, -0.03) micromol/L, respectively. In the younger subjects who quit smoking, tHcy concentrations decreased 0.54 (-0.91, -0.16) micromol/L. Weight changes were inversely related to tHcy. Both baseline history of cardiovascular disease or hypertension and cardiovascular events during follow-up were significantly associated with changes in tHcy.

CONCLUSIONS

Changes in lifestyle factors over time influence tHcy concentrations. These changes are modest when compared with the strong associations between tHcy and lifestyle factors in cross-sectional studies.

Effect of lifestyle factors on plasma total homocysteine concentrations in relation to MTHFR(C677T) genotype. Inter99 (7)

OBJECTIVE

To examine the associations between various lifestyle factors--smoking habits, physical activity, dietary habits, coffee, tea, and alcohol consumption--and homocysteine (tHcy) in relation to MTHFR(C677T) genotype.

DESIGN

Cross-sectional population-based study.

SETTING

Residents of Copenhagen County, Denmark.

SUBJECTS

A random sample of 6457 men and women aged 30-60 years drawn from the Civil Registration System and invited to a health examination in 1999-2001. A total of 2788 participants were included in the statistical analysis.

MAIN OUTCOME MEASURES

tHcy was measured using a Fluorescent Polarization Immuno Assay. MTHFR-genotype was determined by PCR and RFLP analysis. Information about lifestyle factors was obtained from a self-administered questionnaire.

RESULTS

Daily smoking, less healthy dietary habits, and coffee drinking were associated with elevated tHcy concentrations independent of other determinants. Wine consumption was related to tHcy in a J-shaped manner, whereas beer consumption was negatively associated with tHcy after multiple adjustments. Interaction was observed between smoking status and MTHFR-genotype, smoking status and sex, and beer consumption and age. The effect of smoking was more pronounced in persons with the TT genotype and in women. The effect of beer consumption was more pronounced at younger than at older ages.

CONCLUSIONS

Smoking status, dietary habits, coffee intake, wine, and beer consumption were major lifestyle determinants of tHcy. Changes in these lifestyle factors may reduce tHcy concentrations, thereby lowering cardiovascular risk in the general population.

SPONSORSHIP

Danish Medical Research Council, Danish Centre for Evaluation and Health Technology Assessment, and Danish Heart Foundation.

Trigonelline is not responsible for the acute increase in plasma homocysteine following ingestion of instant coffee

OBJECTIVE

To determine whether trigonelline contributes to the effect of coffee on homocysteine (Hcy).

DESIGN AND INTERVENTIONS

This was a randomised crossover study. Subjects consumed 50 mg trigonelline, 5 g of instant coffee (approximately 50 mg trigonelline) or water, consumed as a single dose in 100 ml, with 1 week between each treatment. Blood samples were drawn fasting and hourly for 8 h. Urine samples were collected pretreatment and every 2 h for 8 h.

SETTING

Christchurch Clinical Studies Trust, Christchurch, New Zealand.

SUBJECTS

Eight healthy male subjects.

RESULTS

Instant coffee raised plasma Hcy concentrations compared with water (P=0.019) and trigonelline (P=0.037). Plasma Hcy concentrations were not different between water and trigonelline treatments (P=0.789). The change in plasma Hcy concentration was higher (mean+/-s.e.) 4 h (0.7+/-0.2 micromol/l, P=0.006), 5 h (0.7+/-0.2 micromol/l, P=0.013) and 7 h (0.7+/-0.2 micromol/l, P=0.024) following coffee consumption. Urinary glycine betaine excretion was increased by coffee but not by trigonelline.

CONCLUSION

Ingestion of instant coffee acutely elevated plasma Hcy; however, trigonelline is not responsible for this rise.

SPONSORSHIP

Supported by the Health Research Council, the Canterbury Medical Foundation, the Foundation of Research, Science and Technology.

Critical review of dietary caffeine and blood pressure: a relationship that should be taken more seriously

OBJECTIVE

This review aims to determine whether, and to what extent, dietary caffeine may be a risk to cardiovascular health.

METHODS

A critical review of the relevant experimental and epidemiologic literature was conducted, with particular reference to studies of caffeine and blood pressure (BP).

RESULTS

There is extensive evidence that caffeine at dietary doses increases BP. However, concern that the drug may contribute to cardiovascular disease appears to have been dampened by (1) the belief that habitual use leads to the development of tolerance, and (2) confusion regarding relevant epidemiologic findings. When considered comprehensively, findings from experimental and epidemiologic studies converge to show that BP remains reactive to the pressor effects of caffeine in the diet. Overall, the impact of dietary caffeine on population BP levels is likely to be modest, probably in the region of 4/2 mm Hg. At these levels, however, population studies of BP indicate that caffeine use could account for premature deaths in the region of 14% for coronary heart disease and 20% for stroke.

CONCLUSIONS

Current evidence supports the conclusion that the BP-elevating effects of dietary caffeine may be contributing appreciably to population levels of cardiovascular mortality and morbidity. Accordingly, strategies for encouraging reduced dietary levels of caffeine deserve serious consideration.

Coffee and incidence of diabetes in Swedish women: a prospective 18-year follow-up study

OBJECTIVES

To examine the long-term incidence of diabetes in relation to coffee consumption in Swedish women.

DESIGN

Prospective longitudinal cohort study.

SETTING

City of Göteborg, Sweden.

SUBJECTS

A random population sample of 1361 women, aged 39-65 years, without prior diabetes or cardiovascular disease took part in a screening study in 1979-1981 with questionnaires, physical examination and blood sampling.

MAIN OUTCOME MEASURES

The development of diabetes until 1999 was identified by questionnaires in a second screening and the Swedish hospital discharge register.

RESULTS

Altogether, there were 74 new cases of diabetes. The risk of developing diabetes was 475 per 100 000 person-years in women who consumed two cups of coffee or less per day, 271 in women who consumed three to four cups per day, 202 with a consumption of five to six cups per day, and 267 in drinkers of seven cups or more per day. Associated hazard ratios, after adjustment for age, smoking, low physical activity, education and body mass index were 0.55 (0.32-0.95), 0.39 (0.20-0.77) and 0.48 (0.22-1.06) for daily consumption of three to four, five to six and seven cups or more, respectively, with a consumption of less than two per day as reference. Additional adjustment for serum cholesterol and triglycerides attenuated the relation between coffee and diabetes slightly, indicating a possible mediating effect on the effect of coffee by serum lipids.

CONCLUSIONS

The findings of the present study support the hypothesis that coffee consumption protects from the development of diabetes in women.