The influence of dietary fat on food intake and body weight

Excessive intake of dietary fat is associated with a number of nutrition-related disorders, including obesity, heart disease, and cancer. The over-consumption of fat may be related to its palatability, high energy density, or physiological effects. This article reviews possible reasons why fat intake is high, examines the relationship between diet composition and body weight, and explores potential fat reduction strategies. It is concluded that low-fat or fat-free products could be useful in reducing the percentage of calories derived from fat, although this assertion needs to be further tested in controlled laboratory experiments and validated on a population basis.     

Effect of energy density and fat level of milk formulas on subsequent food and energy intake in preschool children

The aim of this study was to examine the effects of two levels of energy intakes and two levels of fat at breakfast, on the food and energy intakes in subsequent meal (lunch). The study was performed in 51 children both genders, with ages ranging from 24 to 48 months, attending a day care center. The children selected had normal nutritional status (weight/height index) according to the NCHS standards. The food intake was determined by differential weighing and energy intake was calculated from proximal analysis. The energy densities of the cow's milk formula used were 0.8 and 1.2 kcal/g, resulting in a total energy offer (breakfast) of 267.5 and 367.5 kcal respectively, the fat levels were 6.3 and 0.9 g/250 g of formula, using the design 2 x 2 factorial. In the study, 720 observations of food intake were conducted in those children consuming higher than 75% of the total food offered at breakfast. In the lunch-time were offered in alternated form two preparations with an 0.97 kcal/g of energy density. The results demonstrated that the children consumed significantly higher energy amounts in the subsequent meal, after being fed the high fat and lower energy-content breakfast. When the total energy intake (breakfast + lunch) was compared these results show that the caloric difference of breakfast was reduced and the degree of reduction was influenced by the fat level. These results show evidence for partial caloric compensation of 67% in the higher-fat level, and only 34% for the children with the lower of fat-level. It is conclude that the energy intake and fat intake at breakfast influences the energy intake at the subsequent meal. These findings are important to the preschool children's feeding with risk of malnutrition.     

Implications of fat replacement for nutrition and food intake

This article provides specifics on the development of a clinical track for faculty appointments at the University of Pittsburgh. The criteria to be used for appointment and promotion on the clinical track are discussed along with the practice requirements of 60 hours per term of participation in and responsibility for direct care of patients. The purposes of faculty practice are set forth along with the formation and functioning of a Faculty Practice Council which handles decisions related to faculty practice. Results of the first year after implementation of a clinical track showed that 64 per cent (18) of the faculty had met all of their faculty practice obligations; of the remaining 36 percent (10) who had not, a variety of circumstances were cited. The Income to the School of Nursing for faculty practice, although modest, has helped to highlight that practice is valued and an integral part of the faculty role.     

Selective effects of naltrexone on food pleasantness and intake

The effects of 50 mg naltrexone on both pleasantness and intake of 10 common food items were investigated using a double-blind placebo-controlled study with 16 male volunteers. Rated food pleasantness was reduced significantly in the naltrexone condition compared with both controls (placebo and baseline). However, pleasantness ratings were not affected uniformly across foods, with sweetened, fatty, and high-protein foods being most affected. Changes in rated unpleasantness generally mirrored those for pleasantness, but evaluations of saltiness and sweetness were unaffected by naltrexone. Although total intake was reduced in the naltrexone condition, this was not significant compared with placebo. However, fat and protein intakes were significantly less following naltrexone. The effect of naltrexone on intake was also food dependent, but in this case intake of sweet foods was spared relative to other food categories. The apparent discrepancy between liking and intake data with sweet foods could be interpreted in terms of the likely influence of normal eating styles on food selection during a buffet-style meal, and may explain some contradictions in previous studies of this kind. The implications for understanding opioid involvement in food acceptability are discussed.     

Dietary fat intake and the risk of coronary heart disease in women

BACKGROUND: The relation between dietary intake of specific types of fat, particularly trans unsaturated fat and the risk of coronary disease remains unclear. We therefore studied this relation in women enrolled in the Nurses' Health Study. METHODS: We prospectively studied 80,082 women who were 34 to 59 years of age and had no known coronary disease, stroke, cancer, hypercholesterolemia, or diabetes in 1980. Information on diet was obtained at base line and updated during follow-up by means of validated questionnaires. During 14 years of follow-up, we documented 939 cases of nonfatal myocardial infarction or death from coronary heart disease. Mutivariate analyses included age, smoking status, total energy intake, dietary cholesterol intake, percentages of energy obtained from protein and specific types of fat, and other risk factors. RESULTS: Each increase of 5 percent of energy intake from saturated fat, as compared with equivalent energy intake from carbohydrates, was associated with a 17 percent increase in the risk of coronary disease (relative risk, 1.17; 95 percent confidence interval, 0.97 to 1.41; P=0.10). As compared with equivalent energy from carbohydrates, the relative risk for a 2 percent increment in energy intake from trans unsaturated fat was 1.93 (95 percent confidence interval, 1.43 to 2.61; P<0.001); that for a 5 percent increment in energy from monounsaturated fat was 0.81 (95 percent confidence interval, 0.65 to 1.00; P=0.05); and that for a 5 percent increment in energy from polyunsaturated fat was 0.62 (95 percent confidence interval, 0.46 to 0.85; P= 0.003). Total fat intake was not signficantly related to the risk of coronary disease (for a 5 percent increase in energy from fat, the relative risk was 1.02; 95 percent confidence interval, 0.97 to 1.07; P=0.55). We estimated that the replacement of 5 percent of energy from saturated fat with energy from unsaturated fats would reduce risk by 42 percent (95 percent confidence interval, 23 to 56; P<0.001) and that the replacement of 2 percent of energy from trans fat with energy from unhydrogenated, unsaturated fats would reduce risk by 53 percent (95 percent confidence interval, 34 to 67; P<.001). CONCLUSIONS: Our findings suggest that replacing saturated and trans unsaturated fats with unhydrogenated monounsaturated and polyunsaturated fats is more effective in preventing coronary heart disease in women than reducing overall fat intake.     

Independent effects of estradiol on water and food intake.

Conducted 6 experiments to examine the effects of estradiol on ingestive behaviors of guinea pigs. Estradiol treatment was found to reduce water intake independently of its actions on food intake and body weight. In the 1st experiment, minimum intake and body weight of 17 intact female guinea pigs coincided with rupture of the vaginal membrane, the estimated time of ovulation. In Exp II, injections of 3 μg of estradiol benzoate (EB)/day to 7 ovariectomized females significantly depressed food intake, water intake, and body weight, compared with 7 Ss that received oil injections. Reducing food rations to 30% below ad lib levels in Exp III by itself had no significant effect on drinking in ovariectomized Ss. In Exp IV, therefore, ovariectomized females were first placed on a food ration 30% below ad lib levels and then injected daily with either 3 μg of EB or oil. Compared with oil injections, these EB injections significantly reduced water intake, while food intake did not decline significantly. Findings indicate that estradiol operates through different mechanisms to affect water intake and food intake. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dietary fat intake and the risk of incident dementia in the Rotterdam Study

OBJECTIVE: To document prospectively variation in penile morphology and clinical findings in children. PATIENTS AND METHODS: The study comprised a consecutive sample of 468 boys whose consultation with a physician included a genital examination in a primary-care paediatric practice in rural northern Wisconsin. RESULTS: Circumcised boys under 3 years of age were significantly more likely to have a partially or completely covered glans, a reddened meatus, balanitis, or trapped epithelial debris, and less likely to have a fully exposed glans than were circumcised boys of 3 years or older. Among the 238 boys under 3 years, those circumcised were significantly more likely to have non-cosmetic problems, including coronal adhesions, trapped epithelial debris, a reddened meatus, preputial stenosis (phimosis) and balanitis, than were boys with a foreskin. Findings in the circumcised group under 3 years included: fully exposed glans (n = 78, 35.6%), partially covered glans (n = 67, 30.6%), adhesions (25.6%), completely covered glans (20.1%), entrapped desquamated epithelial debris (24.7%), reddened meatus (19.1%), balanitis (15.5%), and preputial stenosis (0.9%). Only two genital examinations in boys with foreskins revealed pertinent findings. Coronal adhesions develop in circumcised boys at 2-6 months of age and usually resolve by 24 months. The degree of skin covering the glans after neonatal circumcision peaks at 6 months of age. CONCLUSIONS: There are significant variations of appearance in circumcised boys; clinical findings are much more common in these boys than previously reported in retrospective studies. The circumcised penis requires more care than the intact penis during the first 3 years of life. Parents should be instructed to retract and clean any skin covering the glans in circumcised boys, to prevent adhesions forming and debris from accumulating. Penile inflammation (balanitis) may be more common in circumcised boys; preputial stenosis (phimosis) affects circumcised and intact boys with equal frequency. The revision of circumcision for purely cosmetic reasons should be discouraged on both medical and ethical grounds.     

Effect of a single high-fat meal on endothelial function in healthy subjects

Incorporation and metabolism of exogenous GM3 in human myelogenous leukemia HL-60 cells were analyzed using 3H-labeled GM3 ([3H]GM3). [3H]GM3 was rapidly internalized into the cells (trypsin-resistant fraction) 8 times more than the control, 3H-labeled GM1 ([3H]GM1). In addition, not only incorporation but also metabolism of [3H]GM3 was more rapid than [3H]GM1 in HL-60 cells. Moreover, one of the metabolites was found to co-migrate with ceramide in thin-layer chromatography analysis and ceramide formation from exogenous GM3 is more rapid than that from exogenous GM1. These results suggested that there would be some preferential mechanism to produce ceramide from differentiation-inducible GM3 in HL-60 cells rather than from non-inducing GM1.     

Use of food nutrition labels is associated with lower fat intake

The colon-targeted delivery capsule (CTDC), a new capsule-type dosage form for colonic delivery of drugs, was investigated for the in vivo drug release behavior in dogs. A CTDC formulation with prednisolone as a model drug and theophylline as a marker substance for gastric emptying was prepared for this study. The enteric-coated capsule (ECC) formulation with a similar composition was also prepared as the reference. Both formulations were administered to four beagle dogs, and the drug release behavior thereof was compared. Under fasted condition, ECC released prednisolone and theophylline at the same time within 1 h after the gastric emptying. On the other hand the CTDC released prednisolone at 3.2 h after the gastric emptying. Such release behavior of CTDC was approximately consistent with the results obtained from the in vitro dissolution study, suggesting that the pH-sensing and timed-release functions imparted to the CTDC can work in the gastrointestinal tract of dogs as programmed. Under non-fasted condition, however, the gastric emptying of CTDC was found to be considerably delayed, up to about 14 h, and in this case the in vivo dissolution lag time of prednisolone at the small intestine was shortened to about 1.5 h.     

Dietary fat intake and risk of lung cancer: a prospective study of 51,452 Norwegian men and women

The relationship between incidence of lung cancer and intake of dietary fats, high-fat foods, fish, and fish products was studied in 25,956 men and 25,496 women aged 16-56 years attending Norwegian health screening between 1977 and 1983. Linkage to the Cancer Registry of Norway and the Central Bureau of Statistics of Norway ensured a complete follow-up until 31 December 1991. Diet was recorded on a semiquantitative food-frequency questionnaire, and 153 cases of lung cancer were identified during follow-up. Mean age at diagnosis was 56 years. After adjusting for smoking status, gender, age at screening, and attained age, significant lower risks were found for cod liver oil supplement (incidence rate ratio (IRR) = 0.5, 95% CI = 0.3-1.0) and for skim milk compared to whole milk (IRR = 0.5, 95% CI = 0.3-0.9)). No association was found with dietary cholesterol and saturated fat. A threshold of increased risk starting at the second quartile was seen for mono- and polyunsaturated fat. The potential protective effect of cod liver oil, a supplement rich in preformed vitamin A, omega-3 fatty acids, and monounsaturated fat, has to our knowledge, not been reported before. Confounding from lifestyle is possible, but the result deserves further investigation.     

Insulin increases the daily food intake of diabetic rats on high and low fat diets

The effects of insulin dose and diet composition on daily food intake were investigated by IV infusion of insulin in doses of 2 to 5 U/day into diabetic rats consuming either a high CHO or high fat diet. The daily food intake of the diabetic rats on both diets increased significantly over baseline levels (p < .01) at the low insulin doses and was maintained at these elevated levels through the 5 U/day dose. Insulin increased the rate of weight gain from Ig/day during baseline to 2 and 2.5 g/day in high CHO and high fat fed diabetics (p < .01). These results show that treatment of diabetic rats with continuous low doses of IV insulin results in a 40% increase in daily food intake regardless of the diet consumed and this increase is accompanied by an increase in rate of body weight gain. While the high fat fed diabetics were relatively hypoglycemic, these increases in intake are not the result of insulin-induced hypoglycemia, since blood glucose concentrations are significantly elevated when the increases occur at the lower insulin doses (p < .01). Thus, peripheralinsulin infused at physiological levels stimulates rather than inhibits daily food intake.     

Dietary fat saturation and chain length modulate guinea pig hepatic cholesterol metabolism

The effects of dietary fat saturation and saturated fatty acid composition on plasma lipoprotein concentrations and hepatic cholesterol metabolism were investigated in guinea pigs. Animals were fed semipurified diets containing 15 g fat/100 g diet, as palm kernel, palm oil, beef tallow, lard, olive oil or corn oil. Plasma lipoprotein concentrations were significantly altered by the type of dietary fat. The LDL cholesterol concentration was highest in animals fed the diet with palm kernel and lowest in animals fed the diet with corn oil, whereas HDL cholesterol was lowest in beef tallow-fed guinea pigs (P < 0.01). Hepatic cholesteryl ester concentrations were 100% higher in animals fed diets containing polyunsaturated corn oil and monounsaturated olive oil compared with animals fed any of the saturated fat diets (P < 0.01). Hepatic 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity varied in the different dietary fat groups independent of hepatic cholesterol pools or plasma LDL concentrations. In contrast, hepatic acyl-CoA: cholesterol acyltransferase (ACAT) activity was significantly correlated with plasma LDL cholesterol across all dietary groups (r = 0.63, P < 0.001). These data demonstrate that regulation of hepatic HMG-CoA reductase activity is relatively independent of changes in plasma lipoprotein levels, whereas hepatic ACAT activity exhibits a positive correlation with plasma LDL cholesterol concentrations.     

Effects of chronic intrahypothalamic infusion of insulin on food intake and diurnal meal patterning in the rat.

In Experiment 1, rats were chronically infused with insulin (2.7, 27, or 270 ng/hr) or 0.9% saline into the ventromedial (VMH), medial perifornical (PF), or lateral (LH) hypothalamus. VMH infusions of insulin caused a significant, dose-dependent decrease in food intake and body weight; PF infusion of insulin was less effective, but significant; whereas LH infusions of insulin were ineffective. In Experiment 2, rats were chronically infused with insulin (0.54 ng/hr) or 0.9% saline into the VMH, paraventricular (PVN), or posterior (PN) hypothalamic nucleus. Subjects that received VMH or PN infusions of insulin failed to regain weight lost as a result of surgery even 2 weeks after infusion; subjects that received PVN infusions of insulin regained their preoperative weights faster than did controls. All of the groups that received insulin significantly increased their daytime food intake during the infusion period and decreased their night food intake slightly; 24-hr food intake remained unchanged. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nutrient intake and food group consumption of 10-year-olds by sugar intake level: the Bogalusa Heart Study

We studied the occurrence of nocturnal enuresis (bedwetting) after the age of 4 years, using a questionnaire in a well-defined population, the Finnish Twin Cohort, which consists of 11,220 subjects aged 33-60 years, including 1298 monozygotic and 2419 dizygotic twin pairs. Structural equation modeling techniques were used to estimate variance components to compare different genetic models. Females reported enuresis in childhood "often" in 3.4% (males in 4.0%) and "sometimes" in 5.7% (8.0%). As adults, females had experienced enuresis "weekly" in 0.3% (males in 0.2%) and "monthly" in 0.07% (0.1%). Those who had experienced enuresis in childhood had had "at least sometimes" enuresis as adults in 5.4% of males and in 5.5% of females. Among those who reported they never had experienced enuresis as adults, 70.8% of males and in 77.9% of females had never experienced enuresis in childhood. For enuresis in childhood, the probandwise concordance rate was 0.43 for monozygotic and 0.19 for dizygotic pairs, and in adults 0.25 and 0, respectively. The proportion of total phenotypic variance attributed to genetic influences (due to dominance) was 67% in males (95% confidence interval 57-76%) and 70% in females (61-78%) in childhood enuresis. In conclusion, nocturnal enuresis is common in childhood and rare in adulthood. Our results confirm the central role of genetic liability in enuresis.     

Negative effects of a high level of nutrient intake on mammary gland development of prepubertal goats

Ten French Alpine kids were used to determine whether mammary development was altered by level of nutrient intake during the prepubertal period. At 6 wk of age, kids were paired on the basis of BW and assigned to an ad libitum or restricted diet of milk from Jersey cows. Kids on the restricted diet were fed 70% of their pair mate's milk intake for 4 wk and then 50% for 9 wk. Low quality grass hay was available for all kids. The ADG was greater for kids fed for ad libitum intake. Kids fed for ad libitum intake had larger mammary glands and increased adipose deposition. Measurement of hydroxyproline indicated that connective tissue increased with gland size. Kids on the restricted diet had more DNA and protein per gram of mammary gland, indicating greater secretory development. Goats can be used as a model to study the effect of level of nutrient intake on hormones and growth factors that regulate mammary gland development.     

Dietary intake and adequacy of vitamin K

OBJECTIVE: To determine how often the fellow eyes of patients with proliferative vitreoretinopathy (PVR) harbor a vision-threatening condition at presentation; to determine how often the fellow eyes of patients with PVR develop vision-threatening conditions; and to determine how often the fellow eyes of patients with PVR lose vision. DESIGN: A retrospective case review design was used. PARTICIPANTS: Two hundred and forty-nine patients with PVR were studied. INTERVENTION: The authors observed the fellow eye of eyes with PVR for vision-threatening pathology. MAIN OUTCOME MEASURES: The primary anatomic endpoint of this study was the detection of vision-threatening pathology in the fellow eye of patients with PVR. Secondary outcome measures included the development of visual loss in the fellow eye. RESULTS: A wide variety of vision-threatening conditions were diagnosed in the fellow eyes of patients with PVR. Of patients meeting entry criteria with reliable follow-up data, greater than 50% of fellow eyes demonstrated vision-threatening pathology at some point during follow-up. CONCLUSIONS: Patients who develop PVR in one eye are at considerable risk for developing vision-threatening pathology or vision-damaging conditions in the fellow eye. This information should be carefully considered when making surgical decisions in patients facing PVR surgery.     

Independent effects of food intake and insulin status on insulin-like growth factor-I in young pigs

The successful use of proteins in pharmaceutical and other commercial applications requires close examination of their relative fragility. Because of the resultant enhanced stability, proteins are often formulated in the solid state, even though dehydration tends to alter their structure. Even in the solid form, however, proteins may become inactivated due to various deleterious processes, e.g., aggregation. This review focuses on such mechanisms, with an emphasis on case studies conducted in our laboratory. Proteins which have both disulfide bonds and free thiols may aggregate via thiol-disulfide exchange, and this process may be facilitated by lyophilization-induced structural perturbations. For proteins possessing disulfides but not free thiols, aggregation also may occur when native disulfides are beta-eliminated, thus giving rise to thiol species which can catalyze disulfide scrambling. Other deleterious processes have also been uncovered, including a formaldehyde-mediated aggregation of formalinized vaccines. It is illustrated how knowledge of such deterioration pathways makes possible the rational development of stable solid protein formulations.