Food sources of calcium in a sample of African-American an Euro-American collegiate athletes

Adequate calcium intake is integral to bone health as well as for optimal athletic performance. This study was conducted to investigate: (a) food sources of calcium in a sample of collegiate athletes, (b) gender and/or ethnic differences in food sources of calcium, and (c) whether athletes that derive less of their calcium intake from dairy sources increase their calcium intake from supplements or other food sources. Participants were African-American and Euro-American NCAA Division 1-A athletes. Eighty-five men and 59 women participated. Calcium intake for the previous 7-day period was assessed with a brief calcium screen. Men consumed significantly more calcium than women (1,354 vs. 898 mg/day), with female cross-country runners exhibiting the lowest average intake (605 mg/day). Both men and women obtained the majority of their calcium from dairy products and mixed dishes, while men consumed significantly more calcium-fortified foods. Several gender and ethnic interactions for calcium intake from food groups were found. Mean total dairy calcium intake was found to vary according to total calcium intake in men, and supplemental calcium was not used to augment low dairy intakes of calcium in any group. While African-Americans and Euro-Americans athletes were consuming similar levels of calcium, the female athletes in the sample did not get adequate amounts.

A meta-analysis of the effects of cigarette smoking on bone mineral density

To determine the magnitude and mediators of the association between cigarette smoking and bone mass in the epidemiologic literature we reviewed articles, published abstracts, and conference proceedings, identified through MEDLINE, psychological abstracts, conference proceedings, and article bibliographies. We studied cross-sectional and prospective human studies that provided a quantitative measure of bone mass (X-ray, absorptiometry, or computed tomography) as a function of cigarette smoking exposure. Effects were expressed as pooled standardized mean differences for categorical comparisons (e.g., bone mass in current versus nonsmokers), and as pooled correlation coefficients for continuous comparisons (e.g., correlation of bone mass and pack-years of smoking). Effects were derived for combined bone sites (all bone sites pooled within each study) and four specific sites (hip, lumbar spine, forearm, and os calcis), and were examined overall and as a function of subject and methodologic characteristics (gender, age, body weight, menopausal status, health status). Data were pooled across 86 studies, enrolling 40,753 subjects. Smokers had significantly reduced bone mass compared with nonsmokers (never and former smokers) at all bone sites, averaging a one-tenth standard deviation (SD) deficit for combined sites. Deficits were especially pronounced at the hip, where the bone mass of current smokers was one-third of a SD less than that of never smokers. Overall, effects were greatest in men and in the elderly, and were dose-dependent. In prospective studies, smokers had greater rates of bone loss over time compared with nonsmokers. Bone mass differences remained significant after controlling for age and body weight differences between the two groups. Absolute effect sizes at most bone sites were greatest for current smokers compared with never smokers, intermediate for current smokers compared with former smokers, and lowest for former smokers compared with never smokers, suggesting that smoking cessation may have a positive influence on bone mass. Based on these data, it is estimated that smoking increases the lifetime risk of developing a vertebral fracture by 13% in women and 32% in men. At the hip, smoking is estimated to increase lifetime fracture risk by 31% in women and 40% in men. It appears that smoking has an independent, dose-dependent effect on bone loss, which increases fracture risk, and may be partially reversed by smoking cessation. Given the public health implications of smoking on bone health, it is important that this information be incorporated into smoking prevention and cessation efforts.

Differences in resting energy expenditure between black and white smokers: implications for postcessation weight gain

OBJECTIVE

To examine differences in resting energy expenditure (REE) between black and white smokers in order to determine whether REE might contribute to postcessation weight gain.

DESIGN

Cross-sectional and prospective investigation of ethnic differences in REE. Differences in REE between black and white smokers were examined at baseline while all participants were smoking, and again during 2 weeks of abstinence from smoking.

SETTING

Memphis, Tennessee, USA.

SUBJECTS

Sixty-six black and 112 white smokers (age 30.4 y; cigarettes per day 21.4; weight 71.7 kg; body mass index 24.5 kg/m2).

RESULTS

Black smokers had a significantly lower baseline REE after adjusting for gender and body weight. Changes in REE following smoking cessation did not differ by ethnicity.

CONCLUSIONS

These results suggest that black smokers may be more energy efficient, which could contribute to ethnic differences in postcessation weight gain.

Smoking cessation in hospitalized patients

The components of readiness to change for smoking cessation that are found in the general population are also applicable to hospitalized smokers. Smoking cessation interventions must be specifically tailored to subgroups among hospitalized patients, with emphasis on smoking-related diagnosis when applicable. Interventions should include key components related to smoking cessation, such as knowledge, self-efficacy, exposure to smoking, and social support. Interventions that include relapse prevention and are conducted in the context of other risk reduction strategies should be developed.

Hostility and the metabolic syndrome in older males: the normative aging study

OBJECTIVE

Several studies have shown that hostility, as measured by the Minnesota Multiphasic Personality Inventory-derived Cook-Medley Hostility Scale (Ho), is positively associated with several cardiovascular risk factors, possibly accounting for the relationship between Ho scores and cardiovascular mortality. This study was undertaken to examine associations between hostility and cardiovascular risk factors representing the metabolic syndrome in 1,081 older men who participated in the Normative Aging Study.

METHODS

Subjects included men who completed the Minnesota Multiphasic Personality Inventory in 1986 and who participated in a subsequent laboratory examination within 1 to 4 years. Total and subscale Ho scores were computed, and associations with anthropometric data, cigarette smoking, dietary information, serum lipids, blood pressure, and fasting glucose and insulin levels were examined.

RESULTS

The total Ho score was positively associated with waist/hip ratio, body mass index, total caloric intake, fasting insulin level, and serum triglycerides. The Ho score was inversely related to education and high-density lipoprotein cholesterol concentration. Path analysis also suggested that the effects of hostility on insulin, triglycerides, and high-density lipoprotein cholesterol were mediated by its effects on body mass index and waist/hip ratio, which, in turn, exerted their effects on lipids and blood pressure through insulin.

CONCLUSIONS

The results are consistent with those of prior research and also suggest that, in older men, hostility may be associated with a pattern of obesity, central adiposity, and insulin resistance, which can exert effects on blood pressure and serum lipids. Furthermore, effects of hostility on the metabolic syndrome appear to be mediated by body mass index and waist/hip ratio.

Predictors of milk consumption in a population of 17- to 35-year-old military personnel

OBJECTIVE

The purpose of this investigation was to survey an entire population of Air Force recruits (N = 32,144) regarding milk consumption and demographic and health-related factors that may predict milk consumption.

DESIGN

All subjects were required to fill out a 53-item health survey at the start of basic military training.

SUBJECTS/SETTING

All recruits who entered the US Air Force from August 1995 to August 1996 participated in this study (N = 32,144).

STATISTICAL ANALYSES PERFORMED

Potential correlates of milk intake were analyzed using Spearman rank order correlations and multiple linear regression. Variables were removed if they did not make a meaningful contribution to variance in milk intake. Because of skewed distributions, several variables were dichotomized (e.g., age: 17 to 24 vs 25 to 35 years).

RESULTS

In terms of milk consumption, 51.7% of the respondents reported intake of fewer than 1 serving per day; only 17.9% reported intake of 3 servings or more per day. Milk intake was positively associated with body weight and fruit/vegetable intake and negatively associated with age, education level, reported milk-related gastric distress, physical activity level, dieting frequency, and concern about weight. Gender (women reported lower intake) and ethnicity (minorities reported lower intake) were independently related to milk consumption. Of all respondents, 16.1% reported themselves to have milk-related gastric distress, but rates varied depending on age, gender, and ethnicity (ranging from 10.2% for younger non-Hispanic white men to 60.4% for older Asian men).

APPLICATIONS/CONCLUSIONS

Despite the efforts of large, costly campaigns designed to increase milk consumption, self-reported milk consumption in young adults is extremely low. Given the importance of dairy products as a major source of calcium in the American diet, dietetics practitioners should assess milk consumption among young adults to ensure sufficient calcium intake to maximize peak bone mass in this group.

The prospective relationships between smoking and weight in a young, biracial cohort: the Coronary Artery Risk Development in Young Adults Study

This study examined the relationship between smoking status and weight change from baseline to Year 7 in a large biracial cohort, the Coronary Artery Risk Development in Young Adults study. Unadjusted for covariates, only male smokers weighed less than nonsmokers, with no effect among women. Adjusted for covariates, male and female smokers weighed less than nonsmokers at baseline, adjusted for age, total energy intake, alcohol intake, and physical fitness. Over the 7-year follow-up, all smoking status groups gained weight, including continuous smokers and initiators. Weight gain was greatest among those who quit smoking. Weight gain attributable to smoking cessation was 4.2 kg for Whites and 6.6 kg for Blacks. Smoking had a small weight-attenuating effect on Blacks. No such effects, however, were observed among Whites. These results suggest, at least in younger smokers, that smoking has minimal impact on body weight.

Gender differences in the outcome of an unaided smoking cessation attempt

There is conflicting evidence concerning gender differences in success at quitting smoking. Information is especially lacking regarding gender differences among unaided quitters who make up the vast majority of those attempting to quit. One hundred thirty-five smokers who made an unaided attempt at quitting were interviewed before quitting and were followed for 1 year after cessation. Relapse rates were extremely high both for men and women, with 62% of participants returning to regular smoking within 15 days after cessation. Women and men were equally likely to maintain short-term abstinence (through 15 days), but women were more than three times as likely to relapse subsequently. Nine percent of men, but no women, had biochemically verified sustained abstinence throughout the 1-year follow-up period. For both men and women, any smoking after the quit attempt inevitably led to full-blown relapse. Most participants resumed regular smoking within 24 hours after the first episode of smoking. Gender differences were observed for several variables related to smoking history, demographics, social support, perceived stress, and motivational factors, but these differences did not explain the increased risk of relapse for women. Our results clearly indicate that women are less likely than men to maintain long-term smoking abstinence following an unaided quit attempt, but reasons for this gender difference need further exploration.

Are weight concerns predictive of smoking cessation? A prospective analysis

Participants in an 8-session, community based smoking cessation intervention rated whether they would stay quit if they experienced weight gain. The majority reported that they would not relapse to smoking, even after a 20-lb, (9.07-kg) weight gain. Those who were weight concerned were more likely to be female, to weight less and be normal or underweight, and to report chronic dieting. This group was also significantly less likely to be abstinent posttreatment, and at the 1-, 6- and 12-month follow-ups. Individuals presenting for formal smoking cessation interventions may be less weight concerned than the general population of smokers. However, weight-concerned smokers who do present for treatment are less likely to quit smoking. Implications for recruitment and intervention are discussed.

Are weight concerns predictive of smoking cessation? A prospective analysis

Participants in an 8-session, community based smoking cessation intervention rated whether they would stay quit if they experienced weight gain. The majority reported that they would not relapse to smoking, even after a 20-lb, (9.07-kg) weight gain. Those who were weight concerned were more likely to be female, to weight less and be normal or underweight, and to report chronic dieting. This group was also significantly less likely to be abstinent posttreatment, and at the 1-, 6- and 12-month follow-ups. Individuals presenting for formal smoking cessation interventions may be less weight concerned than the general population of smokers. However, weight-concerned smokers who do present for treatment are less likely to quit smoking. Implications for recruitment and intervention are discussed.

How much weight gain occurs following smoking cessation? A comparison of weight gain using both continuous and point prevalence abstinence

Estimates of postcessation weight gain vary widely. This study determined the magnitude of weight gain in a cohort using both point prevalence and continuous abstinence criteria for cessation. Participants were 196 volunteers who participated in a smoking cessation program and who either continuously smoked (n = 118), were continuously abstinent (n = 51), or who were point prevalent abstinent (n = 27) (i.e., quit at the 1-year follow-up visit but not at others). Continuously abstinent participants gained over 13 lbs. (5.90 kg) at 1 year, significantly more than continuously smoking (M = 2.4 lb.) and point prevalent abstinent participants (M = 6.7 lbs., or 3.04 kg). Individual growth curve analysis confirmed that weight gain and the rate of weight gain (pounds per month) were greater among continuously smoking participants and that these effects were independent of gender, baseline weight, smoking and dieting history, age, and education. Results suggest that studies using point prevalence abstinence to estimate postcessation weight gain may be underestimating postcessation weight gain.

How much weight gain occurs following smoking cessation? A comparison of weight gain using both continuous and point prevalence abstinence

Estimates of postcessation weight gain vary widely. This study determined the magnitude of weight gain in a cohort using both point prevalence and continuous abstinence criteria for cessation. Participants were 196 volunteers who participated in a smoking cessation program and who either continuously smoked (n = 118), were continuously abstinent (n = 51), or who were point prevalent abstinent (n = 27) (i.e., quit at the 1-year follow-up visit but not at others). Continuously abstinent participants gained over 13 lbs. (5.90 kg) at 1 year, significantly more than continuously smoking (M = 2.4 lb.) and point prevalent abstinent participants (M = 6.7 lbs., or 3.04 kg). Individual growth curve analysis confirmed that weight gain and the rate of weight gain (pounds per month) were greater among continuously smoking participants and that these effects were independent of gender, baseline weight, smoking and dieting history, age, and education. Results suggest that studies using point prevalence abstinence to estimate postcessation weight gain may be underestimating postcessation weight gain.

Changes in bone mineral content in male athletes. Mechanisms of action and intervention effects

OBJECTIVES

To determine changes in bone mineral content (BMC) in male athletes, to examine the mechanisms of changes, and to evaluate the effects of intervention.

DESIGN

Dual-energy x-ray absorptiometry (DEXA) tests were administered over a 2-year period, and calcium loss during training was determined by analysis of sweat and urine. Calcium supplementation was administered during year 2. SETTING--A midsouth university.

PARTICIPANTS

Eleven members of a college Division I-A basketball team.

INTERVENTION

Based on observed calcium loss, athletes received differential levels of calcium supplementation. Intervention commenced the week prior to the fall training season and continued through postseason play. MAIN OUTCOME MEASURE--Changes in BMC.

RESULTS

Total body BMC decreased 3.8% from preseason to midseason of year 1 (mean decrease, 133.4 g, P = .02), increased nonsignificantly by 1.1% (mean increase, 35.3 g, P = .22) during the offseason, but decreased an additional 3.3% during summer months when practices resumed (mean decrease, 113.1 g, P = .01). Dermal calcium loss averaged 247 mg [corrected] per training session. From preseason to late summer, there was an overall decrease of 6.1% in total BMC and a 10.5% decrease in BMC of the legs. Calcium supplementation was associated with significant increases in BMC and lean body mass.

CONCLUSIONS

Bone loss is calcium related and exercise is positively related to BMC provided that calcium intake is sufficient to offset dermal loss.

Influence of insulin, sympathetic nervous system activity, and obesity on blood pressure: the Normative Aging Study

OBJECTIVE

To examine the association of insulin and sympathetic nervous system activity with blood pressure elevation in a cross-sectional study of 752 nondiabetic male participants of the Normative Aging Study, aged 43-90 years.

METHODS

Testing included a physical examination, medical history, fasting and post-carbohydrate insulin and glucose levels determinations, an anthropometric examination, and 24 h urine collection for catecholamine level determination. Total obesity was represented by body mass index, central obesity by the abdomen circumference:hip circumference ratio, and sympathetic nervous system activity by 24 h urinary excretion of norepinephrine.

RESULTS

Systolic and diastolic blood pressure (SBP and DBP, respectively) were positively related to body mass index, abdomen:hip ratio, norepinephrine excretion, and insulin levels in univariate analyses. The relationship between insulin level and SBP and DBP persisted after adjustment for body mass index, abdomen:hip ratio, norepinephrine, age, smoking, physical activity level, and antihypertensive medication use. The norepinephrine level was related to SBP and DBP after adjustment for insulin level, age, smoking, physical activity level, and antihypertensive medication use, and these relationships remained marginally significant after further adjustment for body mass index and abdomen:hip ratio. In contrast, neither body mass index nor abdomen:hip ratio were related to blood pressure after adjustment for insulin level. Among participants in the lowest tertiles both of insulin and of norepinephrine levels, 10% were hypertensive, compared with 35% in the highest tertiles of these variables. In a multiple logistic regression model, insulin level, norepinephrine level, and an interaction term for insulin level with norepinephrine excretion were independent predictors of hypertension.

CONCLUSIONS

The results suggest that insulin level and sympathetic nervous system activity are associated with hypertension among middle-aged and elderly men.

Personality and the incidence of hypertension among older men: longitudinal findings from the Normative Aging Study

Personality predictors of hypertension incidence were studied in 838 community-residing men from the Normative Aging Study. They were followed over a mean of 17 years during which time 38% developed hypertension. Stepwise proportional hazards regression was used to identify scales from the Cattell 16 Personality Factor Questionnaire that predicted hypertension incidence, controlling for biomedical, social, and behavioral risk factors. There was a significant negative relation between the personality trait of emotional stability and the incidence of hypertension, controlling for baseline blood pressure, education, and alcohol consumption. These results support those who argue that personality characteristics predict the development of hypertension.

Relation between saliva cotinine concentration, cigarette consumption, and blood pressure among smokers

In conclusion, we found no evidence of any reduction in blood pressure with greater smoking exposure. For smokers allowed to smoke in a natural manner before blood pressure assessment, greater smoking exposure indexed by saliva cotinine concentration is associated with higher systolic blood pressure levels.

The relationship of epinephrine excretion to serum lipid levels: the Normative Aging Study

Catecholamines are known to stimulate lipolysis of triglyceride stores in adipose tissue. However, the relationship of sympathoadrenal activity to serum lipid and lipoprotein concentrations remains uncertain. Since obesity, particularly the centripetal form, has recently been shown to be associated with increased urinary excretion of norepinephrine and decreased excretion of epinephrine, the possibility that the sympathoadrenal system is involved in the lipid abnormalities associated with the centripetal form of obesity was investigated. The relationship between 24-hour urinary catecholamine excretion and serum lipid and lipoprotein levels was examined among 615 male participants of the Normative Aging Study. Epinephrine excretion was positively correlated with the high-density lipoprotein cholesterol (HDL-C) level and the ratio of HDL-C to low-density lipoprotein cholesterol ([LDL-C] r = .15, P = .0002, and r = .11, P = .007, respectively) and inversely correlated with the triglyceride level (r = -.14, P = .0005). These relationships remained significant after adjusting for the effects of age, smoking, alcohol intake, adiposity, and insulin level. Epinephrine excretion was not significantly related to levels of total cholesterol or LDL-C. Norepinephrine and dopamine excretion were not significantly related to any lipid variable. These data suggest that (1) epinephrine plays an important role in regulating lipid and lipoprotein metabolism in humans, and (2) decreased adrenal medullary activity may contribute to the dyslipidemia (increased triglycerides and decreased HDL-C) commonly observed among the obese. The sympathoadrenal system therefore, along with hyperinsulinemia, may contribute to the increased cardiovascular risk associated with the insulin resistance syndrome.

The relationships of abdominal obesity, hyperinsulinemia and saturated fat intake to serum lipid levels: the Normative Aging Study

Abdominal obesity and hyperinsulinemia are associated with abnormalities in lipid metabolism and are important risk factors for coronary artery disease. Because hyperinsulinemia frequently accompanies abdominal obesity, it is unclear whether each is independently related to lipid abnormalities. Dietary saturated fat may influence these associations since it is associated with elevated lipid levels, obesity and hyperinsulinemia. Abdominal obesity (indexed as abdomen-to-hip circumference ratio), serum insulin level and dietary saturated fat intake were examined in relation to serum levels of lipids and lipoproteins in 878 male participants of the Normative Aging Study. Abdomen-to-hip ratio and insulin level were inversely related to high density lipoprotein cholesterol (HDL-C) (r = -0.17 and -0.21, respectively), and positively related to triglycerides (r = 0.25 and 0.36, respectively). Saturated fat intake was positively related to body mass index (r = 0.20), abdomen-to-hip ratio (r = 0.13), and insulin level (r = 0.10). In multiple linear regression models, abdomen-to-hip ratio was positively related to triglycerides and low density lipoprotein cholesterol (LDL-C) after adjusting for the effects of body mass index, alcohol intake, age, cigarette smoking and physical activity level, but was not significantly related to HDL-C. When serum insulin level was included as a covariate, abdomen-to-hip ratio remained significantly related to LDL-C and triglycerides, although its relationship with triglycerides was attenuated. Insulin level remained inversely related to HDL-C and triglycerides in multivariate models which adjusted for the effects of abdomen-to-hip ratio and BMI.(ABSTRACT TRUNCATED AT 250 WORDS)

Menstrual cycle and dietary restraint influence taste preferences in young women

Previous reports indicate that some women increase their consumption of sugar and fat premenstrually. To ascertain whether this is due to differences in taste acuity for sweetness and fatness and/or preference across the menstrual cycle, 25 female and 12 male undergraduates rated the pleasantness, sweetness, and fatness of 16 taste stimuli made of dairy products with varied fat contents (0%, 3.5%, 10%, 36%) and sucrose (0%, 5%, 10%, 20%) over 4 consecutive weeks. There was a marked decline in ratings over the 4 weeks of testing. Taste preferences of women were not uniform across the menstrual cycle. Those who began testing during the luteal and menstrual weeks had increased preference ratings compared to those who began during the follicular or ovulatory weeks. Preference ratings for taste stimuli containing 0% and 5% sucrose were lower in women with higher scores on a restraint of eating scale, than for women with lower scores. No differences in sweetness or fatness ratings were observed across the menstrual cycle, or as a function of dietary restraint. Men had increased preference for taste stimuli containing 10% and 20% sucrose compared to women; however, no differences in ratings of either sweetness or fatness were found as a function of gender. These data indicate that taste preference in women is not homogeneous across the cycle. Instead, many factors, including the menstrual cycle and degree of eating restraint, influence preference ratings.

Evidence of transient heart rate change after smoking cessation

Heart rate slows immediately after smoking cessation but it is unclear whether this is a permanent or transient effect. Examining this issue may improve our understanding of nicotine withdrawal effects. A transient heart rate pattern would suggest that the cardiovascular system adapts chronically to nicotine and requires a period of adjustment to achieve a new homeostasis after cessation. Heart rate was assessed on 110 smokers prior to quitting and at 1, 3, 8, 15, 30, 45, and 60 days post-cessation. For 12 subjects abstinent 60 days, heart rate slowed at day 1 by 8.1 bpm. Heart rate remained below baseline from days 1 through 45, although exhibiting partial recovery, and returned fully to baseline at day 60. The results indicate that heart rate exhibits a pattern of transient change after smoking cessation which seems to be a physiological effect of nicotine withdrawal.

Changes in urinary catecholamine excretion after smoking cessation

Excretion levels of norepinephrine, epinephrine, and dopamine were assessed in 17 habitual cigarette smokers while smoking and periodically during 30 days of abstinence to determine whether a pattern of transient change existed, suggestive of sympathetic nervous system (SNS) involvement in tobacco withdrawal. Excretion of all three catecholamines declined 1 day after abstinence but did not return to precessation levels during the rest of the follow-up period. The results suggest that postcessation declines in excretion may be permanent changes caused by loss of tobacco's agonist effects, rather than transient withdrawal phenomena resulting from SNS adaptation to the stimulatory effects of tobacco.