The effect of unfiltered coffee on potential biomarkers for colonic cancer risk in healthy volunteers: a randomized trial.

BACKGROUND: Epidemiologic studies suggest that coffee use might protect against colorectal cancer. Inconsistencies as to the effect of coffee use and colorectal cancer between epidemiologic studies might be related to the type of coffee brew. OBJECTIVE: We studied the effect of unfiltered coffee consumption on putative biomarkers for colonic cancer risk. DESIGN: A total of 64 healthy volunteers (31 men and 33 women), with a mean age of 43 +/- 11 years were randomly assigned to two groups in a crossover design, with two intervention periods of 2 weeks separated by a washout period of 8 weeks. Treatments were 1 L of cafetière (French press) coffee daily or no coffee. At the end of each intervention period, fasting blood samples, colorectal biopsies and 48 h faeces were collected. RESULTS: No effect of coffee on colorectal cell proliferation, assayed by estimating the Proliferating Cell Nuclear Antigen labelling index, was seen. Additionally, no effects were seen on the concentrations of faecal soluble bile acids and colorectal mucosal glutathione S-transferase activity. However, unfiltered coffee significantly increased the glutathione content in the colorectal mucosa by 8% and in plasma by 15%. Other aminothiols in plasma also increased on coffee. CONCLUSION: Unfiltered coffee does not influence the colorectal mucosal proliferation rate, but might increase the detoxification capacity and anti-mutagenic properties in the colorectal mucosa through an increase in glutathione concentration. Whether this effect indeed contributes to a lower colon cancer risk remains to be established.

Coffee consumption and serum aminotransferases in middle-aged Japanese men.

We investigated the relation between coffee drinking and serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) concentrations among 7313 Japanese men receiving a health examination, excluding former alcohol drinkers and men with a history of chronic liver disease. Serum AST > 40 and/or ALT > 40 U/L was defined as liver inflammation. Adjustment was made for alcohol use, smoking, body mass index, serum marker for hepatitis virus infection, and other possible confounders. Adjusted odds ratios of liver inflammation were 1.00 (reference), 0.80, 0.69, and 0.61 for men drinking < 1, 1-2, 3-4, and > or = 5 cups of coffee daily, respectively. Among 6898 men without liver inflammation, serum AST and ALT were inversely associated with coffee consumption, and alcohol-related rise in AST was attenuated with coffee drinking. These findings suggest coffee may have an effect of suppressing the rise of serum aminotransferase, partly by inhibiting the alcohol-related elevation. Studies regarding biological mechanism are warranted.

Effects of combined treatment with coffee cherry and whole-body hyperthermia on the growth of spontaneous mammary tumours in SHN mice.

Based on findings that free access in drinking water of the extract of coffee cherry (CC), the residue left after the removal of coffee beans, and whole-body hyperthermia (WBH) induced by far-infrared ray (FIR) can markedly inhibit the growth of spontaneous mammary tumours of SHN mice, the effects of the combined treatment with these agents were examined in this study. The significant inhibition of tumour growth by single treatment with either CC or WBH was not enhanced by their combination. Meanwhile, the body weight loss during WBH was significantly decreased by CC. Normal and preneoplastic growth of mammary glands and plasma component levels were affected little by either treatment. The findings confirmed the "normalization effects" of CC usually obtained with natural products and stress the need for prudence in the choice of any agent, natural or synthetic, to be applied simultaneously to increase the efficacy of WBH.

Chemopreventive effects of coffee bean and rice constituents on colorectal carcinogenesis.

Polyphenolic compound chlorogenic acid (CGA) known to be much contained in coffee beans was found to have a regressive effect on induced aberrant crypt foci (ACF) as well as on development of ACF in azoxymethane (AOM)-induced colorectal carcinogenesis in rats. Rice germ and gamma-aminobutyric acid-enriched defatted rice germ inhibited AOM-induced ACF formation and colorectal carcinogenesis in rats. Ferulic acid (FA) also known to be contained in coffee beans and rice prevented AOM-induced ACF formation and intestinal carcinogenesis in rats. Both of food factors, coffee and rice may be of benefit to prevention of human colorectal cancers.

Use of herbal products, coffee or black tea, and over-the-counter medications as self-treatments among adults with asthma.

BACKGROUND: There are few data on the use of alternative therapies in adult asthma and their impact on health outcomes. OBJECTIVE: The objective of this study was to study the prevalence and morbidity of asthma self-treatment with herbs, coffee or black tea, and over-the-counter (OTC) medications containing ephedrine or epinephrine. METHODS: We carried out a cross-sectional analysis of interview data for 601 adults with asthma recruited from a random sample of pulmonary and allergy specialists. We estimated the 12-month prevalence of reported use of herbal products, coffee or black tea, or OTC products to self-treat asthma and their association with emergency department visits and hospitalization. RESULTS: Herbal asthma self-treatment was reported by 46 (8%; 95% confidence interval [CI] 6% to 10%); coffee or black tea self-treatment by 36 (6%; 95% CI 4% to 8%), epinephrine or ephedrine OTC use by 36 (6%; 95% CI 4% to 8%), and any of the three practices by 98 subjects (16%; 95% CI 13% to 19%). Adjusting for demographic and illness covariates, herbal use (odds ratio [OR] 2.5; 95% CI 1.1 to 5.6) and coffee or black tea use (OR 3.1; 95% CI 1.2 to 7.8) were associated with asthma hospitalization; OTC use was not (OR 0.8; 95% CI 0.3 to 2.5). CONCLUSIONS: Even among adults with access to specialty care for asthma, self-treatment with nonprescription products was common and was associated with increased risk of reported hospitalization. This association does not appear to be accounted for by illness severity or other disease covariates. It may reflect delay in utilization of more efficacious treatments.

Meal frequency and coffee intake in colon cancer.

Several studies suggested that frequent eating may increase colon cancer risk. To further clarify this issue, a case-control study was carried out in six areas of Italy on 1,225 incident cases < 75 years of age with histologically confirmed colon cancer and 4,154 control subjects. The controls were hospitalized for acute, nonneoplastic conditions unrelated to long-term dietary modifications. After allowance for education, physical activity, intake of vegetables, and major energy sources, there was a trend of increasing risk with increasing eating frequency (odds ratio for > or = 4 vs. < or = 2 daily meals = 1.24). Coffee intake, which was inversely associated with cancer risk, exerted a modification effect, with an odds ratio of 1.89 for frequent eaters who drank fewer than two cups of coffee per day. Frequent eating increases, whereas high coffee intake decreases, the excretion of bile acids, which are suspected to be carcinogenic to the colon. Thus, it is conceivable that frequent coffee intake may counterbalance the effect of frequent eating.