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Biomedical subjects

L H Epstein

Publications and source records attributed to L H Epstein.

At least 127 records · Page 7Linked to original sources
PubMed1990

Nutrient intake of obese children in a family-based behavioral weight control program.

The caloric and nutrient intakes, weight, percent overweight and growth of obese and lean children aged 8-12 were compared at baseline and after the obese children participated in a six month family-based behavioral weight control program. At baseline there were no significant differences in the caloric, fat, calcium, iron, vitamin A, vitamin C, thiamin, and riboflavin intakes, or height percentiles of the obese and lean children. After six months the obese children significantly decreased their calorie, protein, fat, and carbohydrate intake, while the lean children significantly increased their protein intake. The percent overweight of the obese children decreased significantly (-18.3 percent), with no changes in percent overweight of the lean children (-0.1 percent). Both the obese (+4.3 cm) and lean (+3.8 cm) children grew significantly over six months, with no significant changes in height percentiles. At baseline and six months both groups exceeded at least two-thirds of the RDA for all nutrients studied.

Age Factors↗
PubMed1989

The effect of nicotine on energy expenditure during light physical activity.

The metabolic effects of nicotine have been implicated in the relation between smoking and lower body weight. This study examined whether the nicotine-induced increase in the metabolic rate observed at rest is also present during physical activity. We compared the energy expenditure of 10 male smokers receiving nicotine (15 micrograms per kilogram of body weight) with that of 10 male smokers receiving placebo on two occasions, each including a period of rest and a period of exercise on a modified bicycle ergometer at workloads designed to simulate and standardize light daily activity. All had abstained from cigarette smoking the night before the study. The excess energy expenditure attributable to nicotine was more than twice as great during exercise (difference between groups, 0.51 kJ per kilogram per hour, or 12.1 percent of the metabolic rate at rest; P less than 0.001) than during rest (0.23 kJ per kilogram per hour, or 5.3 percent of the metabolic rate at rest; P less than 0.05). In contrast, the expenditure was not affected by placebo during exercise or rest in the smokers or in a comparison group of 10 non-smokers, indicating that smoking status has no long-term metabolic effect in the absence of short-term nicotine intake. We conclude that the relatively small metabolic effect of nicotine when the subject is at rest is enhanced during light exercise. Our data also suggest that the weight gain that often follows smoking cessation may be influenced not only by nicotine intake but also by the level of physical activity a smoker typically engages in while smoking.

Adult↗
PubMed1989

The effect of weight control on lipid changes in obese children.

The effects of weight change on serum lipid changes were assessed in a sample of 56 obese children randomly assigned to family-based behavioral obesity treatment vs controls given no treatment. Fasting serum lipid levels, height, weight, and fitness were measured at program entry and after 6 months of treatment. Children assigned to treatment showed significantly greater relative weight and weight changes than children in the control group, and the weight changes were significantly related to reductions in fasting serum triglyceride and total serum cholesterol levels and increases in high-density lipoprotein serum cholesterol. Results after 5 years of follow-up available for a small sample of treated children showed that a change in relative weight and fitness from 6 months to 5 years was also associated with changes in the high-density lipoprotein level. These results suggest that weight control in obese preadolescent children may be associated with improvement in lipoprotein profiles.

Child↗
PubMed1989

Chronic and acute tolerance to the heart rate effects of nicotine.

Tolerance to the effects of nicotine reflects physiological adaptation and may be related to the development and persistence of smoking behavior. However, little is known about tolerance to nicotine in humans, in part due to methodological difficulties. This study examined chronic and acute tolerance to nicotine's effect on heart rate (HR) using a measured-dose nasal spray nicotine procedure. Eight "Light" smokers (less than 20 cigarettes per day) and ten "Heavy" smokers (greater than or equal to 20 per day) participated in two sessions on separate days in which they received four administrations (1 every 20 min) of a high nicotine dose (15 micrograms per kg body weight, equivalent to a typical cigarette) or a low nicotine dose (7.5 micrograms/kg) while HR was monitored during the 5 min following each administration. Compared with Light smokers, Heavy smokers had significantly smaller HR responses to the high dose, indicating greater chronic tolerance, but there was no difference between groups in response to the low dose. Acute tolerance to HR response across the four 5-min periods was not observed with either dose. However, subsequent examination of HR response in the first 2 min following each dose administration did suggest acute tolerance, particularly for the low dose, as this more acute HR response declined from the first to the last administration. These results demonstrate chronic and, to a lesser extent, acute tolerance to HR effects of nicotine and suggest that both may be dose dependent.

Adult↗
PubMed1989

Environment-specific tolerance to nicotine.

Research has shown that tolerance to the behavioral effects of numerous drugs is mediated by learning. The present study was designed to test whether animals develop tolerance to the antinociceptive effects of nicotine, and whether these effects are also learned. Rats were given dally injections of nicotine in the same environment. After each injection, the latency of tail withdrawal from a hot water bath was measured. This was continued until they were tolerant to the drug: i.e., their response latencies did not differ from animals repeatedly given saline. The role of learning in nicotine tolerance was assessed by changing the environment in which they received nicotine on the day after tolerance was achieved. When the drug environment was changed, the animals recovered the full dose effect of nicotine on tail-flick latencies. These results show that tolerance develops to nicotine's antinociceptive effects, and that this tolerance also may be influenced by learning.

Analgesics↗
PubMed1989

Changing environmental cues reduces tolerance to nicotine-induced anorexia.

Male rats on a 22-h food deprivation schedule were injected daily with a low dose of nicotine and allowed to drink sweetened milk for 10 min in a test cage in the colony room. Nicotine initially suppressed milk intake but complete tolerance developed within 10 days so that the amount of intake did not differ from saline controls. The role of temporal cues was tested on the next day by changing the timing of cues, and omitting others that normally preceded nicotine injection while keeping constant the physical environment within which injection and testing took place and the drug-test interval. Changing the timing of injection significantly suppressed milk intake. These results show that tolerance to the anorectic effects of a low dose of nicotine is partially dependent on the presence and timing of cues associated with tolerance acquisition.

Animals↗
PubMed1989

Perception of eating and exercise in children as a function of child and parent weight status.

The present study assessed the effects of child body weight (obese/lean) and familial loading for obesity (two obese parents/two lean parents) on the psychophysics of sweetness, fatness and exercise workloads, as well as subjective ratings of foods varying in sugar and fat and activities varying in energy expenditure. Children were measured in a baseline state and at 6 months after the obese children had participated in a family-based behavioral weight control program. No differences between obese and lean children in perceptual ratings were observed. However, offspring of obese or lean parents differed on intensity rating, food palatability and activity enjoyment ratings. Intensity ratings for sweetness in offspring of obese parents was increased, with a similar trend for intensity ratings for fatness. Offspring of obese parents rated all foods and activities with lower palatability and enjoyment ratings than offspring of lean parents. After a 6 month family-based behavioral weight loss treatment, obese children had significant decreases in percent overweight while lean children remained stable. Changes in the pattern of food ratings were observed for the obese children, with a reduction in liking for foods high in fat and/or sugar, and an increase in ratings for food slower in fat and sugar. The effects of parental obesity on food and exercise intensity ratings and hedonic ratings were maintained. Overall, these results suggest parental weight influences behavioral factors related to obesity in children.

Body Weight↗
PubMed1989

Smoking.

Explore the source record for details and available documents.

Forecasting↗
PubMed1989

Resting metabolic rate in lean and obese children: relationship to child and parent weight and percent-overweight change.

Two studies were conducted to assess differences in metabolic rate as a function of child weight (study I); and the interaction of child and parent weight (study II). In both studies obese children had higher resting metabolic rates (RMRs) than lean children (p less than 0.05). Child weight accounted for 72 and 78% of the variance in RMR in studies 1 and 2, respectively. Including parental weight did not improve the prediction of RMR. After 6 mo of treatment, obese children decreased percent overweight, whereas lean children showed no change (p less than 0.01). RMR in both groups remained unchanged after 6 mo. These results indicate that the RMR is higher in obese than in lean children, that changes in percent overweight that result from increases in height and no change in weight do not decrease RMR over 6 mo, and parent weight does not improve the prediction of child RMR.

Basal Metabolism↗
PubMed1989

Acute effects of nicotine on resting metabolic rate in cigarette smokers.

The acute effects of nicotine on resting metabolic rate (RMR) were examined to identify a mechanism that may help explain the inverse association between smoking and body weight. Multiple administrations of two nicotine doses (moderate [15 micrograms/kg body wt] and low [7.5 micrograms/kg body wt]) and a placebo (0 micrograms) were presented to 18 male smokers via nasal-spray solution on three separate occasions while RMR was assessed by computerized open-circuit indirect calorimetry. Plasma nicotine levels confirmed the reliability of dosing. RMR increases of 6% above base line after both moderate and low doses were significantly greater than the 3% increase after the placebo. Subsequent examination of the effects of smoking a nonnicotine cigarette suggested that the small placebo effect was due to acute metabolic consequences of inhalation. These results confirm that intake of nicotine, isolated from tobacco smoke, significantly increases RMR in humans. However, the results also indicate that non-pharmacological, behavioral aspects of smoking may also contribute to acutely increasing RMR in smokers.

Adolescent↗
PubMed1989

Smoking research: basic research, intervention, prevention, and new trends.

Smoking is a behavior that is influenced by a variety of factors that cut across methodologies, disciplines, and content areas within health psychology. The present article is designed to show the diversity and richness of smoking research by examining smoking from four perspective: basic laboratory research, intervention, prevention and deterrence, and new directions in smoking research. Methodologies that were derived from such varied sources as psychopharmacology, behavioral pharmacology, behavior therapy, clinical psychology, public health and health promotion, and social and developmental psychology have been used to study the smoking problem. The subject populations in these investigations ranged from animal models, to the individual smoker attempting to quit, to communities involved in health promotion and public health approaches. Future research should seek to provide new and improved examples of interdisciplinary research within the field of health psychology to multidisciplinary approaches from the basic and applied sciences.

Humans↗
PubMed1988

Exercise in a behavioural weight control programme for obese patients with Type 2 (non-insulin-dependent) diabetes.

Two studies were conducted to determine whether adding exercise to a diet programme promotes weight loss or glycaemic control in Type 2 (non-insulin-dependent) diabetic subjects. In Study 1, 25 subjects were randomly assigned to diet plus moderate exercise or diet plus placebo exercise. All subjects exercised twice a week as a group and once a week on their own; the diet plus moderate exercise group walked a 3-mile route at each session while the diet plus placebo exercise group did very low intensity exercises such as stretching and light calisthenics. All subjects followed a calorie-counting diet and were taught behaviour modification strategies. Weight losses and improvements in glycaemic control did not differ significantly between the two treatment groups at the end of the 10-week treatment or at 1-year follow-up. In Study 2, more extreme conditions were compared: a diet only group and a diet plus exercise group. The diet plus exercise group walked a 3-mile route with the group 3 times/week and once a week on their own, while the diet only group was instructed to maintain their current low level of activity. Both groups received comparable diet and behaviour modification instruction and therapist contacts. The diet plus exercise group had significantly (p less than 0.01) better weight losses than the diet only condition at the end of the 10 week programme (-9.3 kg vs -5.6 kg) and at 1 year follow-up (-7.9 kg vs -3.8 kg).(ABSTRACT TRUNCATED AT 250 WORDS)

Body Weight↗
PubMed1988

The effects of physical activity as maintenance for smoking cessation.

The effects of physical activity as a maintenance strategy for smoking cessation were evaluated. After a standard smoking cessation program, forty-two women were randomly assigned to one of three groups that received equal number of maintenance meetings: a physical activity program, smoking habit change information and contact control. Abstinence decreased from 83% at the end of treatment to 73% at 3 months, 49% at six months and 34% at 18 months. No differences were shown in cessation across groups. Group differences were shown for subjective levels of tension-anxiety, those who exercised showed increased tension anxiety levels compared to subjects in the no activity groups.

Adult↗
PubMed1988

Long-term relationship between weight and aerobic-fitness change in children.

The relationship between changes in relative weight and fitness was assessed 5 years after children began treatment for obesity. Multivariate regression analysis showed that two factors were independently related to fitness change: (a) maintenance of weight loss from the end of 6 months of treatment to the 5-year follow-up and (b) initial fitness level. Children who showed the largest long-term changes in relative weight and the lowest initial fitness showed the largest improvements in fitness. Short-term weight loss was not related to long-term fitness change. These results show that weight loss and fitness are related over 5 years.

Body Weight↗