Associations of dietary fat, regional adiposity, and blood pressure in men.

Mediterranean populations have low incidence rates of cardiovascular disease and hypertension that may be due, in part, to dietary factors, particularly a relatively high intake of monounsaturated fat as olive oil. In this study, nutritional components (as grams per 4200 kJ) (1 kcal = 4.2 kJ) from three-day food records were examined in association with resting blood pressure in a cross-sectional survey of 76 sedentary middle-aged American men, aged 30 to 55 years, with resting blood pressures below 160/100 mm Hg. Systolic and diastolic blood pressures correlated significantly and inversely with monounsaturated fat consumption. Polyunsaturated fat consumption also correlated inversely with diastolic blood pressure; however, this relationship became nonsignificant when adjusted for an index of regional adiposity that characterizes the male-type obesity pattern. Detailed analyses of specific fatty acids showed that the correlations with monounsaturates were specific to oleic acid, and the correlation with polyunsaturates was specific to linoleic acid. Multiple regression analysis suggested that 18.2% of the variance in systolic blood pressure and 23.2% of the variance in diastolic blood pressure were related to monounsaturated and polyunsaturated fat consumption and regional adiposity. Thus, increased consumption of monounsaturated fat is related inversely to resting blood pressure, although causality remains to be determined.

Alcohol, calorie intake, and adiposity in overweight men.

The relation of alcohol use to calorie intake and adiposity was studied in 155 non-smoking, overweight men. Alcohol use and calorie intake were assessed by 7-day dietary record, and body composition was determined by hydrostatic weighing. Increased intake of food calories (i.e., non-ethanol calories only) on alcohol-drinking days was compensated for by decreased food consumption on non-drinking days of the week. Added alcohol calories were not offset during the week and resulted in a surplus intake of over 4,000 kcal/wk for men in the highest drinking group. Although alcohol calories were "added" to food intake, alcohol use was unrelated to level of adiposity. This finding was not accounted for by concomitant differences in exercise status. Basal metabolic rate, however, was elevated in men imbibing one or more "drinks" per day (as compared to abstainers and light-drinkers). Increased basal energy expenditure may have partially offset the alcohol calories of men at lower levels of alcohol intake, but it did not substantially offset the large calorie surplus seen at higher levels of consumption. Our results support recent speculation that alcohol consumption may not be as "fattening" as traditionally believed.

Relationships of plasma estradiol, testosterone, and sex hormone-binding globulin with lipoproteins, apolipoproteins, and high density lipoprotein subfractions in men.

Plasma estradiol, testosterone, and sex hormone-binding globulin (SHBG) were studied in relation to plasma lipoproteins, high density lipoprotein (HDL) subfractions, and apolipoproteins in 73 healthy but sedentary middle-aged men. Among potentially confounding variables, a strong positive association was found between estradiol levels and cigarette use, while testosterone and SHBG correlated negatively with percent body fat and alcohol intake. After adjustment for smoking, percent body fat, and alcohol, plasma estradiol levels correlated negatively with total cholesterol and low density lipoprotein cholesterol, and testosterone levels correlated positively with apolipoprotein B, while SHBG levels correlated positively with HDL2 mass and apolipoprotein A-I. SHBG was also strongly associated with the waist to hip girth ratio (WHR). Adjustment for WHR eliminated the significant associations of SHBG with triglycerides, HDL2 mass, and apolipoprotein A-I. SHBG levels and WHR may reflect tissue sensitivity and the impact of exposure to fluctuating levels of sex hormones for a period of days, or longer. These variables may provide more insight into the role of sex hormones in lipoprotein metabolism than do single samples of circulating hormones. It is also suggested that long term effects of sex hormones on adipose tissue distribution may at least partially underlie sex-related differences in lipoprotein metabolism.

Correlates of seat-belt use by adolescents: implications for health promotion.

This study examined the psychosocial and behavioral correlates of seat-belt use among 1,728 10th-graders in four Northern California high schools. Parent and friend seat-belt use patterns were most highly correlated with student seat-belt use (r = 0.66 and r = 0.61, respectively) and together accounted for 46% of the variation in use. These relationships held across differences in sex, ethnicity, and socioeconomic status. Failure to wear seat belts was associated with a higher use of alcohol, cigarettes, marijuana, and cocaine; more tolerance toward speeding and drinking while driving; less exercise; and more preference for fat in the diet. Our findings attest to the power of parent and peer influences in shaping seat-belt use by adolescents and suggest that not wearing seat belts can be conceptualized as one facet of a pattern of general risk-taking behavior. These findings suggest several possible educational interventions to increase seat-belt use by adolescents.

Lipoprotein subfractions of runners and sedentary men.

Serum concentrations of lipoprotein mass by flotation rate were measured in 12 long-distance runners and 64 sedentary men by analytic ultracentrifugation. The runners had significantly lower serum mass concentrations of the smaller, denser low-density lipoprotein particles of flotation rates Sf 0-7 (including the LDL-II, LDL-III, and LDL-IV subspecies), very-low-density lipoprotein (VLDL) particles of Sf 20-400, and high-density lipoprotein (HDL) particles of flotation rates F1.20 0-1.5 (predominantly the HDL3 subspecies), and higher serum mass concentrations of HDL particles with flotation rates between F1.20 2.0-9.0 (including HDL2a and HDL2b and less dense particles belonging to HDL3) than did sedentary men. Lipoprotein lipase activity was higher, and hepatic lipase activity was lower in runners than in the sedentary men. Thus, the effects of endurance exercise training to lower LDL may be specific to the smaller, denser LDL particle region. Similarities in the lipoprotein mass profiles of the runners and the low-risk profiles of sedentary, middle-aged women suggest the effects of common metabolic factors possibly leading to reduced risk of coronary artery disease.

Associations of resting heart rate with concentrations of lipoprotein subfractions in sedentary men.

In major prospective studies it has been reported that high heart rate at rest predicts the development of coronary heart disease (CHD) or cardiovascular disease (CVD) in men, but the mechanisms producing these relationships are unknown. Since lipoprotein levels contribute strongly to the risk of CHD and CVD, we examined the relationship of resting heart rate to plasma concentrations of high-density (HDL), low-density (LDL), and very low-density (VLDL) lipoproteins, apolipoprotein (apo) A-I and A-II, and serum concentrations of lipoprotein subfractions in 81 men to determine if atherogenic lipoproteins could potentially induce the reported association of heart rate with development of CHD or CVD. The significant (p less than or equal to .05) Spearman's correlations for resting heart rate vs HDL2 mass (rs = -.24), HDL3 mass (rs = -.40), HDL cholesterol (rs = -.36), apo A-I (rs = -.29), triglycerides (rs = .31), VLDL cholesterol (rs = .24), VLDL mass (rs = .27), and LDL mass of Sof 0-7 subfraction (rs = .30) lend support to our hypothesis of lipoprotein-induced relationships of CHD with heart rate. The correlations for resting heart rate vs triglycerides, HDL cholesterol, HDL3 mass, VLDL mass, and LDL mass of Sof 0-7 subfraction remain significant when adjusted for adiposity, age, smoking habits, diet, and physical fitness as measured by maximum aerobic power (VO2 max) or submaximal heart rate during a graded exercise test.

Coffee intake and elevated cholesterol and apolipoprotein B levels in men.

Coffee intake from three-day diet records was studied in association with plasma lipoprotein concentrations in a cross-sectional sample of 77 middle-aged American men to determine the significance and form of their interrelationships. The number of cups consumed per day correlated positively with levels of apolipoprotein B (r = .27, P less than or equal to .01) and became more strongly correlated when adjusted for age, cigarette use, adiposity, aerobic capacity, nutrient intake, and stress. Coffee intake also correlated with total cholesterol and low-density lipoprotein (LDL) cholesterol levels when adjusted for these confounding factors. Graphic analyses revealed that plasma concentrations of apolipoprotein B and LDL-cholesterol were unrelated to intake of up to 2 cups of coffee per day and positively associated with intake exceeding 2 to 3 cups. These results suggest that male heavy coffee drinkers have lipoprotein profiles suggestive of increased cardiovascular disease risk, although the causality remains to be determined.