Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Caloric Intake”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources
PubMedDate not supplied

Impact of caloric intake on parenteral nutrition-associated intestinal morphology and mucosal barrier function.

BACKGROUND: Parenteral nutrition (PN) is known to induce villus atrophy, epithelial cell (EC) apoptosis, and increase mucosal permeability. The study hypothesized that increasing amounts of energy delivery to mice would result in the best outcome, with the least effects on the mucosa. METHODS: Mice were randomized to enteral controls (saline infusion with ad libitum enteral food) or to 1 of 3 PN groups (with no enteral nutrition): full (100% of daily average energy intake for the mouse), reduced (75% of energy intake) or very low (50% of energy intake). Mice received PN for 7 days. Mucosal morphology, EC apoptosis, and bacterial translocation were assessed. RESULTS: Villus height decreased significantly with decreasing levels of caloric intake and was significantly lower in all PN groups compared with controls. Body weight loss was significantly greater in PN groups vs controls and was greatest in mice with the lowest caloric delivery. A consistent trend toward a higher EC apoptotic index with decreasing caloric intake was observed, and apoptosis in all PN groups exceeded controls (2-fold). All PN groups demonstrated greater bacterial translocation than controls. CONCLUSIONS: PN induces intestinal EC apoptosis and villus and crypt atrophy, even at 100% of predicted energy needs, and such changes increased with greater reduction of energy intake. This study supports a concept that lack of enteral nutrition, rather than absolute caloric levels, is responsible for many of the adverse effects of PN. The study also allows the investigators to better optimize a mouse model of PN delivery.

Animals↗
PubMed1996

Agmatine enhances caloric intake and dietary carbohydrate preference in satiated rats.

Agmatine is a decarboxylated metabolite of arginine endogenous to the brain. In vitro, agmatine inhibits binding of clonidine to alpha 2-adrenergic and imidazoline receptors. We have shown that acute administration of agmatine increases caloric intake and dietary carbohydrate preference in satiated rats. In contrast, agmatine does not modulate caloric intake in hungry rats. Furthermore, repeated administration of high doses of agmatine does not decrease its ability to stimulate appetite.

Agmatine↗
PubMed1992

Photoperiod influences the critical caloric intake necessary to maintain reproduction among male deer mice (Peromyscus maniculatus).

The concept of critical day length is well established among rodents; reproductive function is maintained when day lengths are greater than some specific threshold. In addition to day length cues, seasonal breeding in deer mice can also be regulated by food availability. The caloric threshold necessary to support reproduction remains unspecified for seasonally breeding rodents. The present study examined the interaction between photoperiod and food availability on reproductive function in adult male deer mice (Peromyscus maniculatus). A critical caloric intake profile was constructed in long (16L:8D) and short (8L:16D) photoperiods; groups of deer mice in both photoperiods either received food ad libitum or 90, 80, or 70% of their individual ad libitum food intake for 10 wk. At autopsy, paired testes, epididymides, and seminal vesicles were removed and weighed. Body mass, total body fat, and total body water contents were also obtained. Short, as compared to long, day lengths inhibited the reproductive systems of male deer mice. However, food consumption interacted with photoperiod to affect reproductive function. Significant reductions in reproductive organ size as well as spermatogenic activity were observed among short-day mice after a 10% reduction in ad libitum food intake. Long-day animals required a 20% reduction in caloric intake to depress reproductive function. Body mass and total body water content were generally unaffected by either photoperiod or food consumption. Total body fat content was reduced in short- as compared to long-day mice. Individual reproductive responsiveness to short days increased as food availability decreased.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1976

[Different caloric intake in 75 "low birth weights": effect on weight gain, blood sugar, serum protein, and serum bilirubin (author's transl)].

A prospective study on oral feeding was started in 75 low birth weights (below 2500 g) with adapted milk. Early feeding was given in two groups with different feeding volume and caloric intake. The infants were grouped alternately. Both groups were comparable concerning birth weight, gestational age, and intrauterine growth. Due to partially different variances, covariate correction was applied to analysis of the data. The high caloric group had excellent weight gain, the maximum weight loss was less, and birth weight was regained earlier than in the control group. Blood sugar and serum protein were similar in both groups. Mean serum bilirubin levels were lower in the group with high caloric intake, but differences failed to be significant. Early high caloric feeding was well tolerated and is preferable to parenteral nutrition in low birth weights.

Bilirubin↗
PubMed1992

Influence of parenteral feeding on spontaneous caloric intake and food selection in rats.

We compared spontaneous caloric intake (SCI) of rats exclusively receiving chow to SCI of rats given the choice of chow or Parmesan cheese, and then examined the influence of parenteral feeding on SCI and food selection. Six rats in a Chow Diet Group were offered Purina chow for 21 days, while five rats in a Choice Diet Group were offered Parmesan cheese or the same chow. Daily SCI (kcal/day) and body weight gain (BWG; g/day) were determined. Rats in the Choice Diet Group ate twice as much cheese as chow for the first 3 days of the experiment. Thereafter, SCI and BWG became comparable in both groups, with no significant differences for the rest of the study. In another group of nine rats, a central venous catheter was inserted. After 7 days, rats were offered chow and water ad libitum during the infusion of normal saline at 3 ml/hour for 3 days (Saline). Then, normal saline was replaced by a total parenteral nutrition (TPN) mixture of glucose, fat, and amino acid providing 85 kcal/day, and rats were randomized to eat either Chow Diet or Choice Diet. In both groups, SCI during TPN was significantly reduced as compared to the SCI on Saline. However, rats in the Choice Diet Group ate three times more chow than cheese during TPN. We conclude that a) food preference can increase SCI for short periods of time; b) TPN reduces SCI; c) TPN modifies food preference; and d) food preference does not increase SCI during TPN.

Animals↗
PubMedDate not supplied

Influence of residual renal function on dietary protein and caloric intake in patients on incremental peritoneal dialysis.

OBJECTIVE: To evaluate protein and caloric intake in peritoneal dialysis (PD) patients on an incremental dialysis schedule, in an attempt to discriminate the influence of residual renal function (RRF) on these nutritional parameters. DESIGN: Prospective observational study. PATIENTS: Nine patients who had significant RRF at the beginning of PD therapy, which permitted a schedule of incremental PD (i.e., the number of peritoneal exchanges was increased as the RRF fell) in order to maintain the sum of renal and peritoneal clearance (weekly Kt/V urea) at approximately 2. METHODS: The mean adequacy parameters (urine and peritoneal Kt/V urea and creatinine clearance) along with the mean dietary energy (DEI) and protein intake (DPI) estimated by 3-day diet histories, were determined 6 and 9 months after the beginning of PD, when patients had RRF (period 1), and 6 and 9 months after the loss of RRF (period 2). The mean data obtained in both periods were compared. The best determinants for the changes in DEI and DPI after the loss of RRF were also investigated. RESULTS: Mean total Kt/V urea was very similar in both periods (2.16+/-0.32 vs 2.15+/-0.18), although creatinine clearance decreased significantly after the loss of RRF (74.41+/-12.28 L/week/1.73 m2 vs 56.78+/-11.77 L/week/1.73 m2, p = 0.0001). Absolute and normalized DPI values for actual body weight decreased after the loss of RRF (68.21+/-11.87 g/kg vs 59.27+/-13.66 g/kg, p = 0.02; and 1.17+/-0.32 g/kg/day vs 0.97+/-0.32 g/kg/day, p = 0.01). Although the energy delivered by peritoneal glucose uptake increased significantly after the loss of RRF, the mean total energy intake (DEI plus peritoneal glucose uptake) was very similar in both periods (2141+/-339 kcal/day vs 2010+/-303 kcal/day, p = 0.13). However, the mean total energy intake normalized for actual body weight decreased significantly after the loss of RRF (37.5+/-10.1 kcal/kg/day vs 32.8+/-8.9 kcal/kg/day, p = 0.02). The changes in DEI and DPI between periods 1 and 2 correlated negatively with the difference of the energy delivered by peritoneal glucose uptake (r = 0.65, p = 0.05, and r = 0.88, p = 0.001, respectively). The magnitude of DPI changes between both periods correlated significantly with the magnitude of urinary Kt/V urea changes (r = 0.77, p = 0.01). However, there was no correlation between the changes in DPI and the changes in total Kt/V urea, total or renal creatinine clearance, or the length of time on PD. CONCLUSIONS: The loss of RRF led to a reduction in dietary caloric and protein intake. The magnitude of the reduction in the DPI was strongly correlated with the increase in the energy delivered by peritoneal glucose uptake and with the decrease in the urinary Kt/V urea, but not with the total Kt/V urea.

Adolescent↗
PubMed2003

Differences between estimated caloric requirements and self-reported caloric intake in the women's health initiative.

PURPOSE: To compare energy intake derived from a food frequency questionnaire (FFQ) with estimated energy expenditure in postmenopausal women participating in a large clinical study. METHODS: A total of 161,856 women aged 50 to 79 years enrolled in the Women's Health Initiative (WHI) Observational Study (OS) or Clinical Trial (CT) [including the Diet Modification (DM) component] completed the WHI FFQ, from which energy intake (FFQEI) was derived. Population-adjusted total energy expenditure (PATEE) was calculated according to the Harris-Benedict equation weighted by caloric intakes derived from the National Health and Nutrition Examination Survey. Stepwise regression was used to examine the influence of independent variables (e.g., demographic, anthropometric) on FFQEI-PATEE. Race, region, and education were forced into the model; other variables were retained if they increased model explanatory ability by more than 1%. RESULTS: On average, FFQEI was approximately 25% lower than PATEE. Regression results (intercept=-799 kcal/d) indicated that body mass index (b=-23 kcal/day/kg.m(-2)); age (b=15 kcal/day/year of age); and study arm (relative to women in the OS, for DM women b=169 kcal/d, indicating better agreement with PATEE) increased model partial R(2)>.01. Results for CT women not eligible for DM were similar to those of women in the OS (b=14 kcal/d). There also were apparent differences by race (b=-152 kcal/d in Blacks) and education (b=-67 kcal/d in women with<high school). CONCLUSION: This large, carefully studied population confirms previous observations regarding underestimates in self-reported caloric intake relative to estimates of metabolic need in younger women, and those with higher weight, with less education, and in Blacks. These differences, along with effects related to intervention assignment, underline the need for additional research to enhance understanding of errors in dietary measurement.

Aged↗
PubMed1975

Effect of thermal environment and caloric intake on head growth of low birthweight infants during late neonatal period.

In order to assess the effects of ambient thermal conditions on postnatal head growth in low birth weight infants, 42 asymtomatic neonates were reared under 4 combinations of caloric intake and thermal environment after the first week of life. Exposure to a subthermoneutral temperature (abdominal skin temperature of 35 degrees C), together with a relatively low caloric intake (120 cal/kg per day), was associated with significant retardation of head growth over a 2-week study period.

Birth Weight↗
PubMedDate not supplied

Estimating age-related changes in psychomotor function: influence of practice and of level of caloric intake in different genotypes.

This article presents a discussion of some key considerations in the measurement of age-related changes in psychomotor function of mice. We illustrate that "standard" measures of psychomotor performance, such as running speed on a rotorod task, are highly sensitive to practice effects. Examples are cited in which failure to assess practice effects can influence conclusions regarding the magnitude and rate of change in psychomotor capacity as a function of age. A second set of examples is focused on estimating the effect of an experimental intervention, caloric restriction, on age-related changes in psychomotor performance. These examples show that psychomotor performance at a given age may vary directly, and reversibly, with the level of caloric intake. Independent of such reversible effects, the level of caloric intake can also modulate the rate of change in capacity as a function of age. It is concluded that reversible, short-term effects must be considered in estimating the effect of an experimental intervention on the rate of age-associated change in psychomotor function.

Aging↗
PubMed1990

The influence of pre- and postnatal caloric intake on colon carcinogenesis.

Mother rats were allowed to litter under conventional conditions. They were fed a complete, semipurified diet during gestation, and at time of littering the numbers of pups were reduced to either eight per litter or four per litter in two additional groups. At weaning, all rats were continued on the same diet that their mothers had consumed. One group of those reduced to four per litter at birth was allowed to continue to eat ad libitum while the other group, reduced to four per litter, was pair fed to the ad libitum eight per litter group. The group reduced to four per litter at birth and allowed to eat ad libitum during postnatal life gained the most weight and were heaviest at the termination of the study. This group also had the greater incidence and frequency of colon tumors when exposed to dimethylhydrazine (DMH). The group pair fed to rats fed conventional diets, eight rats per litter, had an incidence and frequency of tumors between the other two groups. These data demonstrate that early exposure to excess calories increased risk for cancer and that early and late excess caloric intake further increased risk. Thus, pre- and perinatal caloric intake may have a significant influence on susceptibility to cancer later in life. Mechanisms are only speculative but may include differences in metabolism and modulation of hormonal balance.

Animals↗
PubMed1977

Fenfluramine and fluoxetine spare protein consumption while suppressing caloric intake by rats.

The effects of fenfluramine and other sanorectic drugs on the consumption of both protein and total calories by rats given simultaneous access to two isocaloric diets containing 5 or 45 percent casein were examined. Anorectic doses of fenfluramine failed to decrease protein intake but increased the proportion of total dietary calories represented by protein. In contrast, anorectic doses of d-amphetamine decreased protein and calorie consumption proportionately. Subanorectic doses of fenfluramine also increased the proportion of caloric intake represented by protein among animals given prior treatment with the serotonin precursor tryptophan. Fluoxetine, a drug that blocks reuptake of serotonin, similarly spared protein consumption while reducing caloric intake. These observations indicate that two distinct brain mechanisms, sensitive to different drugs, underlie the elective consumption of protein and calories.

Animals↗
PubMedDate not supplied

Caloric intake and hypothalamic neurotransmitters in Zucker rats made acutely diabetic with streptozocin.

Zucker rats, lean and obese, treated with low dose intraperitoneal injections of streptozocin become hyperglycemic within 24h. Insulin levels fall, although the obese animal remains hyperinsulinemic. Associated with these changes in glucose and insulin there are transient decreases in caloric intake. Macronutrient selection studies show that protein consumption decreases. There is a trend for fat intake to decrease. The levels of hypothalamic neurotransmitters in the lean animals are not altered by streptozocin. The levels of 5-hydroxyindoleacetic acid increases in the streptozocin-treated obese animal in the paraventricular region, ventromedial region and the raphe. Serotonin is also significantly increased in the paraventricular region of the obese rat. These results suggest that acutely, treatment with streptozocin injures pancreatic islets, causing, in turn, decreases in insulin levels so that hyperglycemia ensues in both phenotypes. Associated with these perturbations are decreases in caloric intake. The magnitude of change in insulin levels is much greater in the obese rat. It is hypothesized that in the obese Zucker rat decrements in food intake are mediated by increase in serotonin turnover in the hypothalamus and these changes are related to changes of insulin levels. These data support the concept that circulating insulin affects hypothalamic neurotransmitters.

Animals↗
PubMed1980

Pulmonary excretion of carbon monoxide in the human infant as an index of bilirubin production. IV. Effects of breast-feeding and caloric intake in the first postnatal week.

Measurements of the pulmonary excretion rate of carbon monoxide (VEco) as an index of bilirubin production in the first several days of life were taken from 64 breast-fed or bottle-fed infants. Twenty-one infants (greater than or equal to 37 weeks of gestation) were breast-fed; 43 infants (28 to 42 weeks of gestation) were bottle-fed a commercially prepared formula. Information pertaining to their caloric intake during the 24-hour period preceding VEco determination was taken from 38 of the 43 infants who were bottle-fed and they were placed into three groups based on their caloric intake: (1) less than or equal to 60 kcal/kg/day (19 infants); (2) 61 to 100 kcal/kg/day (7 infants); and (3) greater than 100 kcal/kg/day (12 infants). There was no significant difference in bilirubin production between bottle-fed and breast-fed infants. No effect of caloric deprivation on bilirubin production was demonstrated. The mean VEco values were 18.5 +/- 0.9 (SE) for group 1, 17.7 +/- 1.8 (SE) for group 2, and 16.2 +/- 1.1 (SE) microliter/kg/hr for group 3.

Bilirubin↗
PubMed2001

Effect of morphine on caloric intake and macronutrient selection in male and female Lou/c/jall rats during ageing.

Previous studies have showed a shift of preferences from carbohydrate to fat in the Lou/c/jall rat with advancing age when they are submitted to a self-selection procedure. Protein intake also decreased according to the age, earlier for males (after 16 months) than for females (29 months). The present study aimed at investigating the mechanism underlying these modifications. We analysed the effect of the reference mu agonist, morphine (5 mg/kg subcutaneous), on the caloric intake, body weight and macronutrient intake of 30 male and 30 female rats divided in four age groups: young adults (10), mature (17), old (24) and senescent rats (29 months). During the experiment, animals had the choice between separate sources of the three pure macronutrients. Morphine injection reduced total daily caloric intake and induced a decrease in body weight. The weight loss was age- and sex-related (males and old rats were more affected by the drugs). The injection of morphine evoked a triphasic influence on the chronology of the intake. A brief (1 h) hypophagia was followed by an hyperphagia (3 h) and a persistent hypophagia (8 h). No modification in the diet composition was observed. These results did not support a clear involvement of the opioid system concerning the modifications in macronutrient rates in diet previously observed across ageing.

Aging↗
PubMed1999

Body fat, caloric intake, and plasma leptin levels in women with anorexia nervosa.

OBJECTIVE: To measure serum leptin concentrations in women with anorexia nervosa (AN) and to identify independent predictors of leptin levels, thereby allowing hormone levels to be modeled using regression analysis. METHODS: A cross-sectional study of 15 AN inpatients and 16 healthy control subjects. Age, height, weight, percent body fat, total caloric intake, fat intake, and fasting plasma leptin levels were recorded. Stepwise forward regression analysis was carried out to identify predictors of leptin levels. RESULTS: Circulating leptin concentrations in AN were 3.5+/-0.5 versus 7.6+/-1.2 ng/ml in control subjects. Percent body fat correlated best with leptin levels in anorexic and control subjects (r =.63; p =.0002), with caloric intake showing only a moderate correlation (r = .47; p = .008). Only percent body fat was a significant predictor of plasma leptin levels in our regression model. DISCUSSION: Leptin levels are proportionately lower in AN as compared to healthy controls. It appears that physiological regulation of plasma levels with respect to percent body fat is maintained in individuals with little body fat.

Adipose Tissue↗
PubMed1997

Caloric intake and weight gain of rats depends on endogenous fat preference.

Within outbred colonies, subpopulations of rats exist that exhibit inherent preferences for one type of macronutrient over another (e.g., fat vs. carbohydrate). Prior investigations into the effect of dietary manipulations on consumption or weight gain have not taken into account endogenous macronutrient preferences. The purpose of this study was to examine whether inherent fat preferences translate into differences in caloric consumption and weight gain in rats when fed high-fat and high-carbohydrate diets. Rats that exhibited a preference for fat were identified using a previously described paradigm and were subsequently placed on either a high-fat or high-carbohydrate diet. Daily caloric intakes and weekly weights were monitored over a 28-day period and compared with data for animals with a low-fat preference on the same diets. By the conclusion of the study, the low-fat-preferring rats on the high-carbohydrate diet had consumed significantly more calories than the high-fat-preferrers maintained on the same diet. In contrast, the amounts of calories consumed on the high-fat diet were not significantly different between the low- and high-fat-preferring animals. Those animals with a preference for fat placed on a high-carbohydrate diet weighed significantly less by the end of study, even though they consumed the same number of calories as animals on the high-fat diet. We conclude that the outcome of nutritional studies designed to examine caloric intake and weight gain can be influenced by the innate macronutrient preference of the animal.

Animals↗
PubMed1989

Adjustment of caloric intake based on self-monitoring in noninsulin-dependent diabetes mellitus: development and feasibility.

It has been recommended that patients who perform self-blood glucose monitoring use the information gained from the test to alter their diabetic regimen. Skyler et al. have proposed algorithms for patients to adjust their insulin dosage when blood sugar is elevated. However, the clinical result of increasing insulin dosage may be the promotion of weight gain. We proposed that altering the regimen by decreasing caloric intake is an appropriate first approach for NIDDM patients for whom weight loss would be of considerable benefit. Results of an initial needs assessment showed that patients did not generally regard testing and adjusting therapy as important in taking care of diabetes. A recent study by Fox et al. reported similar results, showing that a large portion of patients using blood glucose self-monitoring do not make changes in their regimen when they know that their blood sugar is elevated. Consequently, we implemented a half-day seminar to instruct patients on making adjustments in their dietary regimen on the basis of results of glucose monitoring. Results suggest that our teaching methods were effective in teaching patients to follow the adjusting algorithm. Although we observed trends toward improved metabolic control and weight loss, further studies are required to document the clinical benefit of adjustment of caloric intake based on self-monitoring in diabetes.

Algorithms↗
PubMed1986

Sources of variance in milk and caloric intakes in breast-fed infants: implications for lactation study design and interpretation.

Between-individual variation (BIV) and day-to-day variation (DDV) of total caloric and human milk intakes were examined in 17 infants. Nine were studied at months 5 and 6; 8 at months 6 and 7. All 17 were exclusively breast-fed for 5 full mo after which solid foods were added to the diet. Each infant was studied for five consecutive 24-h periods during which serial measurements were made of milk intake (test weighing) and solid food intake (pre- and postfeeding jar weighing). Total daily caloric intakes (kcal/day) were (mean +/- SD) 492 +/- 57, 547 +/- 70, and 567 +/- 98 at months 5, 6, and 7, respectively. Estimates of caloric intakes (kcal/kg/day) adjusted for body weight were 65.9 +/- 6.7, 72.6 +/- 11.2, and 70.9 +/- 13.0 at months 5, 6, and 7, respectively. Milk intakes (g/day) were 735 +/- 85, 640 +/- 106, and 562 +/- 214 at months 5, 6, and 7, respectively. BIV of milk intake increased after the introduction of solid foods. DDV (expressed as coefficient of variation) of caloric intake was nearly constant at each monthly observation and BIV increased from 8.8 at month 5 to 14.6 at month 7. The numbers of 24-h periods and subjects required for estimates of known precision of caloric and milk intakes of older breast-fed infants can be determined from these estimates of variance.

Adult↗