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.

Coffee drinking and serum gamma-glutamyltransferase: an extended study of Self-Defense Officials of Japan.

PURPOSE: To examine the effect of coffee drinking on serum gamma-glutamyltransferase (GGT) level in relation to alcohol drinking, smoking, and degree of obesity in middle-aged Japanese men. METHODS: From 1986 to 1994, a total of 7,637 male officials of the Self-Defense Forces of Japan aged 48-59 years received a preretirement health examination. Coffee drinking was ascertained by a self-administered questionnaire, and serum GGT level was measured. After excluding 1,360 men with a possible pathologic condition influencing liver enzyme levels and 182 former alcohol drinkers, effect of coffee drinking on serum GGT was examined by a multiple linear regression model and analysis of variance adjusting for alcohol drinking, smoking, and body mass index (BMI). RESULTS: The adjusted percentage of difference in serum GGT was -4.3 (95% CI = -5.0; -3.5) per cup of coffee. The inverse coffee-GGT relation was most prominent among men drinking > or = 30 ml of ethanol and smoking > or = 15 cigarettes daily; and positive associations of alcohol and smoking with GGT were attenuated by coffee drinking, more clearly among men with BMI > or = 25.00 kg/m2. Adjusted percentages of difference in serum GGT were -2.6% (p = 0.0003) per cup of brewed coffee, and -5.1% (p = 0.0001) per cup of instant coffee, independently of each other. CONCLUSIONS: The present study suggests that coffee consumption may weaken GGT-induction by alcohol, and possibly by smoking. These effect modifications by coffee may differ according to the degree of obesity.

Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan.

The study aims to examine the relationship between habitual coffee consumption and blood pressure. The subjects were 3336 male self-defense officials aged 48-56 years, who received a preretirement health examination at the Self-Defense Forces Fukuoka Hospital between October 1986 and December 1992. Average coffee intake in the past year was ascertained by a self-administered questionnaire. A significant inverse relation between habitual coffee consumption and blood pressure was found with and without adjustment for alcohol use, cigarette smoking, body mass index, glucose tolerance, and green tea intake. Green tea, another major source of caffeine intake in Japanese, was unrelated to blood pressure. The adjusted mean differences per cup of coffee consumed per day were -0.6 mmHg (95% confident interval [CI]: -0.9 to -0.3, p = 0.0001) in systolic blood pressure and -0.4 mmHg (95% CI: -0.5 to -0.2, p = 0.0002) in diastolic blood pressure. Habitual coffee drinkers had lower blood pressure than non-drinkers at any levels of alcohol use, cigarette smoking, obesity, and glucose intolerance. Our findings consolidate the previous observation that habitual coffee consumption was associated with lower blood pressure.

Bioavailability of rumen bacterial selenium in mice using tissue uptake technique.

A tissue uptake experiment was conducted to determine the bioavailability of rumen bacterial Selenium (Se) in mice. The donor animal was wether fed a diet containing 0.2 mg Se/kg dietary dry matter (DM). Ruminal fluid was collected 2 h postprandially. Bacterial-rich precipitate was obtained by differential centrifugation of the ruminal fluids. This was later freeze-dried and mixed in the diet to be used in feeding the mice experiment. Thirty growing female mice with a body wt (mean +/- SD) of 21.4 +/- 0.74 g were housed in plastic cages (5 mice/cage) and allotted equally to three dietary treatments. Diet 1 and Diet 2 were formulated based on AIN-76, except that no Se supplementation in the form of selenite was made in the former. In Diet 3, rumen bacterial matter was 20% of the diet, which gave an equivalent of 0.1 mg Se/kg dietary DM. The other two diets, Diet 1 and Diet 2, had an Se content of 0.025 and 0.1 mg/kg dietary DM, respectively. A 7-d feeding commenced after 7 d of acclimatization of the semipurified diet. Results showed that those mice fed an Se- (selenite) supplemented diet (Diet 2) had higher (P < 0.05) tissue Se concentrations than those mice fed the other two diets. No statistical differences were observed on various tissue Se concentrations between Diet 1 and Diet 3, although the latter diet had higher values. Kidney and liver had the highest Se concentrations compared to the other tissues. This study concludes that bacterial Se collected from the rumen of wether is not fully available for absorption in the intestine of the mice.

Anticipation of job loss or job change and cardiovascular risk factors: a study of retiring self-defense officials in Japan.

Self-defense officials in Japan are to retire at the age of early 50s. This unique situation prompted the authors to investigate whether preexisting morbid conditions cause any difficulty in finding a post-retirement job and whether anticipation of job loss or job change, as measured by the status of post-retirement job and months remaining until retirement, was related to biological cardiovascular risk factors. The subjects were 2,228 male self-defense officials who received a preretirement health examination at three Self-Defense Forces Hospitals from 1991 to 1992; the period in time remaining until retirement ranged from 1-40 months (median 12 months), and 62% had one year or less until the retirement. The defined preexisting illnesses included a wide range of chronic, non-communicable diseases. Overall, the preexisting illness was unrelated to the determination of a post-retirement job. In men having 6 months or less until retirement, however, the security of post-retirement job was less frequent when they had the preexisting illness, especially cardiovascular diseases. In 1,839 men excluding those with the preexisting illness, the period until retirement was not adversely related to obesity, blood pressure, serum lipids, serum uric acid, or glucose intolerance whether the post-retirement job had been secured or not. The findings suggest that the preexisting illness decreases the chance of obtaining a post-retirement job, but do not provide any evidence that anticipation of job loss or job change due to early retirement exerts an adverse effect on biological cardiovascular risk factors.

Relation of green tea consumption to serum lipids and lipoproteins in Japanese men.

Animal experiments have shown a hypocholesterolemic effect of green tea extracts. Only few epidemiological studies have addressed the relation between green tea consumption and serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C). This paper examined the relation of green tea consumption to serum lipids and lipoproteins in 2,062 male self-defense officials in Japan, aged 49-55 years, who received a preretirement health examination at three hospitals of the Self-Defense Forces in 1991-1992. A self-administered questionnaire queried the consumption of green tea and a limited number of other dietary items as well as lifestyle characteristics. After adjustment for body mass index, waist-hip ratio, smoking, alcohol use, exercise, rank, and hospital, green tea consumption was inversely associated with serum levels of TC and LDL-C, but not with either high density lipoprotein cholesterol or triglycerides. Rice consumption was positively correlated with green tea consumption, and also was associated independently with lower levels of TC and LDL-C. Additional adjustment for rice, however, did not change the results. Daily drinking of 10 cups of green tea was associated with differences of 6.2 mg/dl in TC (95% confidence interval [CI] 0.4-12.1) and 6.2 mg/dl in LDL-C (95% CI 0.7-11.7). These findings of association of green tea with blood cholesterol hint at a possible causal relationship, which requires confirmation by further studies in humans using different methods.

Coffee and serum gamma-glutamyltransferase: a study of self-defense officials in Japan.

The relation of coffee drinking and other behavioral factors to serum gamma-glutamyltransferase (GGT) was examined in 2,494 male self-defense officials aged 48-56 years, who received a retirement health examination at the Self-Defense Forces Fukuoka Hospital between October 1986 and December 1990. Coffee, but not green tea, consumption was inversely related to serum GGT independently of body mass index, alcohol use, and smoking. All of the latter variables were also independently and positively associated with serum GGT. Lower levels of serum GGT associated with coffee drinking were more evident among heavier alcohol drinkers and also among heavier smokers. The findings suggest that coffee may inhibit the inducing effects of alcohol and possibly of smoking upon GGT in the liver.

Alcohol consumption and blood pressure: an extended study of self-defence officials in Japan.

BACKGROUND: It remains controversial whether the relation between alcohol intake and blood pressure is linear or non-linear. METHODS: The relation between alcohol intake and blood pressure was investigated in 2341 male self-defence officials who received a preretirement health examination at the Self-Defense Forces Fukuoka Hospital between October 1986 and December 1990. Average alcohol intake in the past year was ascertained by a self-administered questionnaire. The study excluded past drinkers, and allowed for smoking, body mass index and glucose tolerance. RESULTS: Blood pressure was higher at higher levels of alcohol intake across the range from 0 to 40-59 ml of alcohol per day, but was not progressively higher in men consuming > or = 60 ml per day. Blood pressure was significantly higher even among light drinkers (< 20 ml per day) compared to non-drinkers; adjusted mean differences were 3.1 mmHg (95% confidence interval (CI): 1.1-5.2) in systolic pressure and 2.1 mmHg (95% CI: 0.7-3.5) in diastolic pressure. CONCLUSIONS: Our findings do not support the existence of a threshold in the relation between alcohol and blood pressure.

Green tea consumption and serum lipid profiles: a cross-sectional study in northern Kyushu, Japan.

METHODS. The relation between green tea consumption and serum lipid concentrations was examined using cross-sectional data on 1,306 males who received the retirement health examination at the Self-Defense Forces Fukuoka Hospital between October 1986 and December 1988. RESULTS. After adjustment for rank, smoking, alcohol use, physical activity, and body mass index, serum total cholesterol levels were found to be inversely related to the consumption of green tea while no association was noted with serum triglycerides and high-density lipoprotein cholesterol. Adjusted mean concentrations of total cholesterol were 8 mg/dl lower in men drinking nine cups or more per day than in those consuming zero to two cups per day. Serum cholesterol levels were inversely associated with traditional Japanese dietary habits (intake of rice and soy bean paste soup) and positively associated with Westernized habits. Additional adjustment for these dietary variables did not alter the inverse relation between green tea and total cholesterol.

Physical activity, dietary habits and adenomatous polyps of the sigmoid colon: a study of self-defense officials in Japan.

Physical activity and dietary habits were compared between 80 men with adenomatous polyps of the sigmoid colon and 1148 men with normal colonoscopy among male retiring self-defense officials. Physical activity as expressed in terms of time spent doing strenuous activities during leisure time was inversely related to the risk of adenomatous polyps. Controlling for rank, smoking, alcohol and body mass index (BMI), odds ratios for the categories of 0, 1-59, 60-119 and greater than or equal to 120 minutes per week were 1.0, 0.88, 0.70 and 0.44, respectively (trend p = 0.015). Among a limited range of foods and beverages, the consumption of rice, green tea and instant coffee tended to be associated with a decreased risk of adenomatous polyps. Although the associations observed with dietary habits still need to be substantiated, the findings on physical activity lend further evidence to the hypothesis that physical activity may be protective in the development of colon cancer.