Instruct: Given a question, retrieve relevant passages that answer the question.
Query: trans fat
Background Dietary trans fatty acids (dTFA) are primarily synthetic compounds that have been introduced only recently; little is known about their behavioral effects. dTFA inhibit production of omega-3 fatty acids, which experimentally have been shown to reduce aggression. Potential behavioral effects of dTFA merit investigation. We sought to determine whether dTFA are associated with aggression/irritability. Methodolgy/Prinicpal Findings We capitalized on baseline dietary and behavioral assessments in an existing clinical trial to analyze the relationship of dTFA to aggression. Of 1,018 broadly sampled baseline subjects, the 945 adult men and women who brought a completed dietary survey to their baseline visit are the target of this analysis. Subjects (seen 1999–2004) were not on lipid medications, and were without LDL-cholesterol extremes, diabetes, HIV, cancer or heart disease. Outcomes assessed adverse behaviors with impact on others: Overt Aggression Scale Modified-aggression subscale (primary behavioral endpoint); Life History of Aggression; Conflict Tactics Scale; and self-rated impatience and irritability. The association of dTFA to aggression was analyzed via regression and ordinal logit, unadjusted and adjusted for potential confounders (sex, age, education, alcohol, and smoking). Additional analyses stratified on sex, age, and ethnicity, and examined the prospective association. Greater dTFA were strongly significantly associated with greater aggression, with dTFA more consistently predictive than other assessed aggression predictors. The relationship was upheld with adjustment for confounders, was preserved across sex, age, and ethnicity strata, and held cross-sectionally and prospectively. Conclusions/Significance This study provides the first evidence linking dTFA with behavioral irritability and aggression. While confounding is always a concern in observational studies, factors including strength and consistency of association, biological gradient, temporality, and biological plausibility add weight to the prospect of a causal connection. Our results may have relevance to public policy determinations regarding dietary trans fats. Clinicaltrials.gov # NCT00330980
This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessment of intake of food additives. A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives: branching glycosyltransferase from Rhodothermus obamensis expressed in Bacillus subtilis, cassia gum, cyclamic acid and its salts (dietary exposure assessment), cyclotetraglucose and cyclotetraglucose syrup, ferrous ammonium phosphate, glycerol ester of gum rosin, glycerol ester of tall oil rosin, lycopene from all sources, lycopene extract from tomato, mineral oil (low and medium viscosity) class II and class III, octenyl succinic acid modified gum arabic, sodium hydrogen sulfate and sucrose oligoesters type I and type II. Specifications for the following food additives were revised: diacetyltartaric acid and fatty acid esters of glycerol, ethyl lauroyl arginate, glycerol ester of wood rosin, nisin preparation, nitrous oxide, pectins, starch sodium octenyl succinate, tannic acid, titanium dioxide and triethyl citrate. Annexed to the report are tables summarizing the Committee's recommendations for intakes and toxicological evaluations of the food additives considered.
BACKGROUND: Dietary fat type is known to modulate the plasma lipid profile, but its effects on plasma homocysteine and inflammatory markers are unclear. OBJECTIVE: We investigated the effects of high-protein Malaysian diets prepared with palm olein, coconut oil (CO), or virgin olive oil on plasma homocysteine and selected markers of inflammation and cardiovascular disease (CVD) in healthy adults. DESIGN: A randomized-crossover intervention with 3 dietary sequences of 5 wk each was conducted in 45 healthy subjects. The 3 test fats, namely palmitic acid (16:0)-rich palm olein (PO), lauric and myristic acid (12:0 + 14:0)-rich CO, and oleic acid (18:1)-rich virgin olive oil (OO), were incorporated at two-thirds of 30% fat calories into high-protein Malaysian diets. RESULTS: No significant differences were observed in the effects of the 3 diets on plasma total homocysteine (tHcy) and the inflammatory markers TNF-α, IL-1β, IL-6, and IL-8, high-sensitivity C-reactive protein, and interferon-γ. Diets prepared with PO and OO had comparable nonhypercholesterolemic effects; the postprandial total cholesterol for both diets and all fasting lipid indexes for the OO diet were significantly lower (P < 0.05) than for the CO diet. Unlike the PO and OO diets, the CO diet was shown to decrease postprandial lipoprotein(a). CONCLUSION: Diets that were rich in saturated fatty acids prepared with either PO or CO, and an OO diet that was high in oleic acid, did not alter postprandial or fasting plasma concentrations of tHcy and selected inflammatory markers. This trial was registered at clinicaltrials.gov as NCT00941837.
BACKGROUND & AIMS: Taste sensitivity to fatty acids influences food ingestion and may regulate fat intake and body weight status. Fatty acids are detected via homologous receptors within the mouth and gastrointestinal (GI) tract, where attenuated sensitivity may be associated with greater fat intake and BMI. This study aimed to extend observations surrounding fatty acid taste, specifically the types of foods consumed and dietary behaviours that may be associated with fatty acid taste sensitivity. METHODS: 51 subjects (41 female; BMI, 21.4 ± 0.46 kg/m², age, 20 ± 0.52 yrs, 10 male; BMI, 23.6 ± 1.4 kg/m², age, 22 ± 1 yrs) were screened for oral sensitivity to oleic acid (3.8 mM) using triplicate sensory evaluations, and classified as hypersensitive; (3/3 correct identifications), or hyposensitive, (<3/3). Fat-taste perception (using sensory-matched custards made with 0, 2, 6, 10% oil), recent diet (4-day diet record) and food habits and behaviours (food habits and behaviours questionnaire) were also established. RESULTS: 75% (n = 38) of subjects were classified as hyposensitive to oleic acid and these subjects differed from those who were classified as hypersensitive. Hyposensitive subjects consumed significantly more energy, fat, saturated fat, fatty foods (butter, meat, dairy), had greater BMI and were less perceptive of small changes in the fat content of custard (all P < 0.05), compared to hypersensitive subjects. CONCLUSION: An inability to perceive low concentrations of fatty acids in foods was associated with greater consumption of fatty foods, specifically butter, meat, dairy, and increasing BMI. 2011 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
The cardiovascular risk reduction associated with different statins for the prevention of cardiovascular disease and the cardiovascular risk increase associated with excess dietary intake of fat have been quantified. However, these relative risks have never been directly juxtaposed to determine whether an increase in relative risk by 1 activity could be neutralized by an opposing change in relative risk from a second activity. The investigators compared the increase in relative risk for cardiovascular disease associated with the total fat and trans fat content of fast foods against the relative risk decrease provided by daily statin consumption from a meta-analysis of statins in primary prevention of coronary artery disease (7 randomized controlled trials including 42,848 patients). The risk reduction associated with the daily consumption of most statins, with the exception of pravastatin, is more powerful than the risk increase caused by the daily extra fat intake associated with a 7-oz hamburger (Quarter Pounder) with cheese and a small milkshake. In conclusion, statin therapy can neutralize the cardiovascular risk caused by harmful diet choices. In other spheres of human activity, individuals choosing risky pursuits (motorcycling, smoking, driving) are advised or compelled to use measures to minimize the risk (safety equipment, filters, seatbelts). Likewise, some individuals eat unhealthily. Routine accessibility of statins in establishments providing unhealthy food might be a rational modern means to offset the cardiovascular risk. Fast food outlets already offer free condiments to supplement meals. A free statin-containing accompaniment would offer cardiovascular benefits, opposite to the effects of equally available salt, sugar, and high-fat condiments. Although no substitute for systematic lifestyle improvements, including healthy diet, regular exercise, weight loss, and smoking cessation, complimentary statin packets would add, at little cost, 1 positive choice to a panoply of negative ones.
Transglutaminase is an enzyme that can be used to cross-link pieces of meat, fish or meat products. The resulting product gives the optical impression of an intact chunk of meat. The usage of transglutaminase as a food additive is permitted in some countries. However, its utilisation has to be declared to ensure transparency for consumers. This paper describes two orthogonal analytical methods suited for the detection of technological relevant transglutaminase concentrations (around 25 mg pure enzyme in 1 kg of product) in meat and meat products. The mass spectrometry-based approach relies on a previous digestion with Achromobacter lyticus protease and LC-MS/MS separation and detection. Sufficient selectivity was obtained by monitoring four different peptides. The orthogonal (complementary and independent), ELISA-based approach relies on two commercially available bacterial transglutaminase-specific antibodies, combined to a sandwich ELISA. The two methods were tested by analysing some 60 samples obtained from the market.
OBJECTIVE: In 1976, the Royal College of Physicians and the British Cardiac Society recommended eating less fatty red meat and more poultry instead because it was lean. However, the situation has changed since that time, with a striking increase in fat content of the standard broiler chicken. The aim of the present study was to report a snapshot of data on fat in chickens now sold to the public. DESIGN: Samples were obtained randomly between 2004 and 2008 from UK supermarkets, farm shops and a football club. The amount of chicken fat was estimated by emulsification and chloroform/methanol extraction. SETTING: Food sold in supermarkets and farms in England. SUBJECTS: Chicken samples. RESULTS: The fat energy exceeded that of protein. There has been a loss of n-3 fatty acids. The n-6:n-3 ratio was found to be as high as 9:1, as opposed to the recommendation of about 2:1. Moreover, the TAG level in the meat and whole bird mostly exceeded the proportion of phospholipids, which should be the higher for muscle function. The n-3 fatty acid docosapentaenoic acid (DPA, 22 : 5n-3) was in excess of DHA (22 : 6n-3). Previous analyses had, as usual for birds, more DHA than DPA. CONCLUSIONS: Traditional poultry and eggs were one of the few land-based sources of long-chain n-3 fatty acids, especially DHA, which is synthesized from its parent precursor in the green food chain. In view of the obesity epidemic, chickens that provide several times the fat energy compared with protein seem illogical. This type of chicken husbandry needs to be reviewed with regard to its implications for animal welfare and human nutrition.
This experiment aimed to study the molecular toxicity of methylmercury (MeHg) in liver, brain and white muscle of Atlantic salmon fed a diet based on fish oil (FO, high dietary n-3/n-6 ratio) compared to an alternative diet mainly based on vegetable oil (VO, low dietary n-3/n-6 ratio). Juvenile salmon were fed decontaminated diets or the FO and VO diets enriched with 5 mg Hg/kg (added as MeHg) for three months. The dietary lipid composition affected the fatty acid composition in the tissues, especially in liver and white muscle. After 84 days of exposure, the liver accumulated three times as much MeHg as the brain and white muscle. Vitamin C content and heme oxygenase, tubulin alpha (TUBA) and Cpt1 transcriptional levels all showed significant effects of MeHg exposure in the liver. TBARS, α-tocopherol, γ-tocopherol, and the transcriptional levels of thioredoxin, heme oxygenase, TUBA, PPARB1, D5D and D6D showed an effect of dietary lipid composition in liver tissue. Effects of dietary lipids were observed in brain tissue for MT-A, HIF1, Bcl-X and TUBA. Interaction effects between MeHg exposure and dietary lipid composition were observed in all tissues. Our data suggest that dietary fats have modulating effects on MeHg toxicity in Atlantic salmon. Copyright © 2011 Elsevier Ltd. All rights reserved.
BACKGROUND: Elevated serum saturated fatty acid levels and hepatocyte lipoapoptosis are features of nonalcoholic fatty liver disease (NAFLD). AIM: The purpose of this study was to investigate saturated fatty acid induction of lipoapoptosis in human liver cells and the underlying mechanisms. METHODS: Human liver L02 and HepG2 cells were treated with sodium palmitate, a saturated fatty acid, for up to 48 h with or without lithium chloride, a glycogen synthase kinase-3β (GSK-3β) inhibitor, or GSK-3β shRNA transfection. Transmission electron microscopy was used to detect morphological changes, flow cytometry was used to detect apoptosis, a colorimetric assay was used to detect caspase-3 activity, and western blot analysis was used to detect protein expression. RESULTS: The data showed that sodium palmitate was able to induce lipoapoptosis in L02 and HepG2 cells. Western blot analysis showed that sodium palmitate activated GSK-3β protein, which was indicated by dephosphorylation of GSK-3β at Ser-9. However, inhibition of GSK-3β activity with lithium chloride treatment or knockdown of GSK-3β expression with shRNA suppressed sodium palmitate-induced lipoapoptosis in L02 and HepG2 cells. On a molecular level, inhibition of GSK-3β expression or activity suppressed sodium palmitate-induced c-Jun-N-terminal kinase (JNK) phosphorylation and Bax upregulation, whereas GSK-3β inhibition did not affect endoplasmic reticulum stress-induced activation of unfolded protein response. CONCLUSIONS: The present data demonstrated that saturated fatty acid sodium palmitate-induced lipoapoptosis in human liver L02 and HepG2 cells was regulated by GSK-3β activation, which led to JNK activation and Bax upregulation. This finding indicates that GSK-3β inhibition may be a potential therapeutic target to control NAFLD.
Saturated fatty acids (SFAs) produce an inflammatory response. Hyperinflammation is now recognized as one of the key underlying etiologic factors in periodontal disease. The longitudinal relationship between dietary SFAs and periodontal disease in 264 Japanese individuals, aged 75 years, for whom data were available for the years 2003-2004, was investigated. SFA intake was assessed with a brief self-administered diet history questionnaire. Participants were classified by quartiles of SFA intake. Full-mouth periodontal status, measured as the clinical attachment level (CAL), was recorded at baseline and follow-up examinations. The number of teeth with a loss of CAL≥3 mm at any site over a year was calculated as 'periodontal disease events'. Poisson regression analysis was conducted, with dietary SFAs as the primary predictor of interest, to estimate their influence on periodontal disease events. High dietary SFA intake was significantly associated with a greater number of periodontal disease events among non-smokers. The multivariate adjusted relative risk (95% confidence intervals) in the 1st, 2nd, 3rd, and 4th quartiles of dietary SFAs was 1.00, 1.19 (0.72-1.97), 1.55 (0.95-2.52), and 1.92 (1.19-3.11), respectively. These findings suggest an independent association of dietary SFA intake to the progression of periodontal disease in older Japanese non-smokers. ABBREVIATIONS: saturated fatty acid (SFA); clinical attachment level (CAL); Toll-like receptor (TLR); lipopolysaccharide (LPS); brief self-administered diet history questionnaire (BDHQ); decayed, missing, and filled teeth (DMFT); clinical attachment level (CAL); body mass index (BMI); relative risk (RR); confidence intervals (CI); nuclear factor-kappa B (NF-κB).
Objective To relate dietary fat types to cognitive change in healthy community-based elders. Methods Among 6,183 older participants in the Women’s Health Study, we related intake of major fatty acids (FAs) (saturated [SFA], mono-unsaturated [MUFA], total poly-unsaturated [PUFA], trans-unsaturated) to late-life cognitive trajectory. Serial cognitive testing, conducted over 4 years, began 5 years post-dietary assessment. Primary outcomes were global cognition (averaging tests of general cognition, verbal memory and semantic fluency) and verbal memory (averaging tests of recall). We used analyses of response profiles and logistic regression to estimate multivariable-adjusted differences in cognitive trajectory and risk of worst cognitive change (worst 10%) by fat intake. Results Higher SFA intake was associated with worse global cognitive (p-linear-trend=0.008) and verbal memory (p-linear-trend=0.01) trajectories. There was a higher risk of worst cognitive change, comparing highest vs. lowest SFA quintiles: the multivariable-adjusted odds ratio (OR) (95% confidence interval, CI) was 1.64 (1.04,2.58) for global cognition and 1.65 (1.04,2.61) for verbal memory. By contrast, higher MUFA intake was related to better global cognitive (p-linear-trend<0.001) and verbal memory (p-linear-trend=0.009) trajectories, and lower OR (95% CI) of worst cognitive change in global cognition (0.52 [0.31,0.88]) and verbal memory (0.56 [0.34,0.94]). Total fat, PUFA, and trans fat intakes were not associated with cognitive trajectory. Interpretation Higher SFA intake was associated with worse global cognitive and verbal memory trajectories, while higher MUFA intake was related to better trajectories. Thus, different consumption levels of the major specific fat types, rather than total fat intake itself, appeared to influence cognitive aging.
Increased consumption of plant products is associated with lower chronic disease prevalence. This is attributed to the great diversity of healthy phytochemicals present in these foods. The most investigated physiological effects have been their antioxidant, anti-carcinogenic, hypolipidemic, and hypoglycemic properties. Although less studied in humans, some compounds were very early on shown to be lipotropic in animals, i.e., the capacity to hasten the removal of fat from liver and/or reduce hepatic lipid synthesis or deposits by mainly increasing phospholipid synthesis via the transmethylation pathway for triglyceride-rich lipoprotein exportation from the liver and enhanced fatty acid β-oxidation and/or down- and up-regulation of genes involved in lipogenic and fatty acid oxidation enzyme synthesis, respectively. The main plant lipotropes are choline, betaine, myo-inositol, methionine, and carnitine. Magnesium, niacin, pantothenate, and folates also indirectly support the overall lipotropic effect. The exhaustive review of rat studies investigating phytochemical effect on hepatic lipid metabolism suggests that some fatty acids, acetic acid, melatonin, phytic acid, some fiber compounds, oligofructose, resistant starch, some phenolic acids, flavonoids, lignans, stilbenes, curcumin, saponins, coumarin, some plant extracts, and some solid foods may be lipotropic. However, this remains to be confirmed in humans, for whom intervention studies are practically non-existent. Supplemental materials are available for this article. Go to the publisher's online edition of Critical Reviews in Food Science and Nutrition® to view the free supplemental file.
Many changes in diet and in physical activity are occurring simultaneously in the developing world. These diet shifts include large increases in energy density, in the proportion of the population consuming a high fat diet and in animal product intake. Animal source foods (ASF) play a major role in these diet shifts. This article documents the large shifts in the composition of diets and obesity across the developing world and notes that these changes are accelerating. Using China as a case study, evidence of the speeding up of this process is presented in descriptive and more rigorous dynamic longitudinal analysis. The implications of these changes for dietary and obesity patterns and cardiovascular disease are great. Indeed, developing countries are at a point where the prevalence of obesity is greater than that of undernutrition and concerns related to intake of saturated fat and energy imbalance must be considered more seriously by the agriculture sector. Current agriculture development policy in many developing countries focuses on livestock promotion and does not consider the potential adverse health consequences of this strategy. Although linkages between ASF intake and obesity cannot be established as clearly as they are for high ASF intakes, heart disease and cancer, the potential adverse health effects linked with an increased ASF intake should no longer be ignored.
BACKGROUND: Olestra is a nonabsorbable, energy-free fat substitute. Because it is not absorbed, it may cause digestive symptoms when consumed in large amounts. OBJECTIVE: To compare the frequency and impact of gastrointestinal symptoms in adults and children who freely consume snacks containing olestra or regular snacks in the home. DESIGN: 6-week, double-blind, randomized, parallel, placebo-controlled trial. SETTING: General community. PARTICIPANTS: 3181 volunteers 2 to 89 years of age. INTERVENTION: Households received identical packages labeled as containing olestra corn or potato chips. These packages contained either olestra or regular chips (control). MEASUREMENT: Gastrointestinal symptoms and their impact on daily activities were reported in a daily record. RESULTS: At least one gastrointestinal symptom was reported by 619 of 1620 (38.2%) persons in the olestra group and 576 of 1561 (36.9%) controls (difference, 1.3 percentage points [95% CI, -3.6 to 6.2 percentage points]; P = 0.60). In general, the groups did not differ significantly in the proportion of participants who reported individual gastrointestinal symptoms; however, more controls reported nausea (8.4% compared with 5.7%; difference, -2.7 percentage points [CI, -4.9 to -0.4 percentage points]; P = 0.02). The only difference between groups for the mean numbers of days on which symptoms were reported was that participants in the olestra group had 1 more symptom-day of more frequent bowel movements than did controls (3.7 symptom-days compared with 2.8 symptom days; difference, 0.9 symptom-days [CI, 0.1 to 1.8 symptom-days]; P = 0.04). The groups did not differ in the impact of symptoms on daily activities. CONCLUSIONS: Clinically meaningful or bothersome gastrointestinal effects are not associated with unregulated consumption of olestra corn and potato chips in the home.
OBJECTIVE: Since conventional food questionnaires are not precise in assessing the dietary fatty acids, the purpose of this study was to determine the relationship between the salivary fatty acid profile and the alimentary habits of two different groups in an attempt to develop a more reliable way to determine the lipidic intake. DESIGN: Twenty adults of both sexes, with mixed (M) or vegetarian (V) diets were studied. Data about the fat intake were obtained by means of a Food Frequency Questionnaire (FFQ) and the presence of the main salivary fatty acids was determined by gas chromatography. RESULTS: A greater salivary concentration of alpha-linolenic acid (18:3 n-3) (2.82) was found in V than in M subjects (1.65) (p = 0.001), whilst arachidonic acid (20:4 n-6) was lower in V (3.93) than in M (4.52) (p = 0.045). The same difference regarding arachidonic acid was observed in the dietary fatty acid intake, also showing a significant correlation between its dietary and salivary levels in vegetarian subjects. CONCLUSIONS: These results show that salivary arachidonic acid, relevant for their eicosanoid production related to the tumourigenesis process and cardiovascular diseases, is influenced by dietary fats.
Obesity has important health consequences, including elevating risk for heart disease, diabetes, and cancer. A high-fat diet is known to contribute to obesity. Little is known regarding the effect of a high-fat diet on pulmonary function, despite the dramatic increase in the prevalence of respiratory ailments (e.g., asthma). The purpose of our study was to determine whether a high-fat meal (HFM) would increase airway inflammation and decrease pulmonary function in healthy subjects. Pulmonary function tests (PFT) (forced expiratory volume in 1-s, forced vital capacity, forced expiratory flow at 25-75% of vital capacity) and exhaled nitric oxide (eNO; airway inflammation) were performed in 20 healthy (10 men, 10 women), inactive subjects (age 21.9 +/- 0.4 years) pre and 2 h post HFM (1 g fat/1 kg body weight; 74.2 +/- 4.1 g fat). Total cholesterol, triglycerides, and C-reactive protein (CRP; systemic inflammation) were determined via a venous blood sample pre and post HFM. Body composition was measured via dual energy X-ray absorptiometry. The HFM significantly increased total cholesterol by 4 +/- 1%, and triglycerides by 93 +/- 3%. ENO also increased (p < 0.05) due to the HFM by 19 +/- 1% (pre 17.2 +/- 1.6; post 20.6 +/- 1.7 ppb). ENO and triglycerides were significantly related at baseline and post-HFM (r = 0.82, 0.72 respectively). Despite the increased eNO, PFT or CRP did not change (p > 0.05) with the HFM. These results demonstrate that a HFM, which leads to significant increases in total cholesterol, and especially triglycerides, increases exhaled NO. This suggests that a high-fat diet may contribute to chronic inflammatory diseases of the airway and lung.
Two populations of immigrants to London and to the West Indies from the Indian subcontinent have higher than expected morbidity and mortality from atherosclerosis but do not show the commonly accepted major risk factors. This study investigated the hypothesis that ghee, a clarified butter product prized in Indian cooking, contains cholesterol oxides and could therefore be an important source of dietary exposure to cholesterol oxides and an explanation for the high atherosclerosis risk. Substantial amounts of cholesterol oxides were found in ghee (12.3% of sterols), but not in fresh butter, by thin-layer and high-performance-liquid chromatography. Dietary exposure to cholesterol oxides from ghee may offer a logical explanation for the high frequency of atherosclerotic complications in these Indian populations.
AIMS/HYPOTHESIS: Prolonged elevation of plasma specific fatty acids may exert differential effects on glucose-stimulated insulin secretion (GSIS), insulin sensitivity and clearance. SUBJECTS AND METHODS: We examined the effect of oral ingestion, at regular intervals for 24 h, of an emulsion containing either predominantly monounsaturated (MUFA), polyunsaturated (PUFA) or saturated (SFA) fat or water (control) on GSIS, insulin sensitivity and insulin clearance in seven overweight or obese, non-diabetic humans. Four studies were conducted in each individual in random order, 4-6 weeks apart. Twenty-four hours after initiation of oral ingestion, subjects underwent a 2 h, 20 mmol/l hyperglycaemic clamp to assess GSIS, insulin sensitivity and insulin clearance. RESULTS: Following oral ingestion of any of the three fat emulsions over 24 h, plasma NEFAs were elevated by approximately 1.5- to 2-fold over the basal level. Ingestion of any of the three fat emulsions resulted in reduction in insulin clearance, and SFA ingestion reduced insulin sensitivity. PUFA ingestion was associated with an absolute reduction in GSIS, whereas insulin secretion failed to compensate for insulin resistance in subjects who ingested SFA. CONCLUSIONS/INTERPRETATION: Oral ingestion of fats with differing degrees of saturation resulted in different effects on insulin secretion and action. PUFA ingestion resulted in an absolute reduction in insulin secretion and SFA ingestion induced insulin resistance. Failure of insulin secretion to compensate for insulin resistance implies impaired beta cell function in the SFA study.
BACKGROUND: Saturated fat intake has been associated with both cardiovascular disease and cancer risk, and a newly published study found an association between saturated fat intake and a lower sperm concentration in infertile men. OBJECTIVE: The objective was to examine the association between dietary fat intake and semen quality among 701 young Danish men from the general population. DESIGN: In this cross-sectional study, men were recruited when they were examined to determine their fitness for military service from 2008 to 2010. They delivered a semen sample, underwent a physical examination, and answered a questionnaire comprising a quantitative food-frequency questionnaire to assess food and nutrient intakes. Multiple linear regression analyses were performed with semen variables as outcomes and dietary fat intakes as exposure variables, adjusted for confounders. RESULTS: A lower sperm concentration and total sperm count in men with a high intake of saturated fat was found. A significant dose-response association was found, and men in the highest quartile of saturated fat intake had a 38% (95% CI: 0.1%, 61%) lower sperm concentration and a 41% (95% CI: 4%, 64%) lower total sperm count than did men in the lowest quartile. No association between semen quality and intake of other types of fat was found. CONCLUSIONS: Our findings are of potentially great public interest, because changes in diet over the past decades may be part of the explanation for the recently reported high frequency of subnormal human sperm counts. A reduction in saturated fat intake may be beneficial for both general and reproductive health.
The aim of these studies was to evaluate the potential of some nutritional approaches to prevent or reduce the body load of organochlorines (OC) in humans. Study 1 compared plasma OC concentrations between vegans and omnivores while study 2 verified if the dietary fat substitute olestra could prevent the increase in OC concentrations that is generally observed in response to a weight-reducing programme. In study 1, nine vegans and fifteen omnivores were recruited and the concentrations of twenty-six OC (beta-hexachlorocyclohexane (beta-HCH), p, p'-dichlorodiphenyldichloroethane (p, p'-DDE), p, p'-dichlorodiphenyltrichloroethane (p, p'-DDT), hexachlorobenzene, mirex, aldrin, alpha-chlordane, gamma-chlordane, oxychlordane, cis-nonachlor, trans-nonachlor, polychlorinated biphenyl (PCB) nos. 28, 52, 99, 101, 105, 118, 128, 138, 153, 156, 170, 180, 183 and 187, and aroclor 1260) were determined. In study 2, the concentrations of these twenty-six OC were measured before and after weight loss over 3 months in thirty-seven obese men assigned to one of the following treatments: standard group (33 % fat diet; n 13), fat-reduced group (25 % fat diet; n 14) or fat-substituted group (1/3 of dietary lipids substituted by olestra; n 10). In study 1, plasma concentrations of five OC compounds (aroclor 1260 and PCB 99, PCB 138, PCB 153 and PCB 180) were significantly lower in vegans compared with omnivores. In study 2, beta-HCH was the only OC which decreased in the fat-substituted group while increasing in the other two groups (P = 0.045). In conclusion, there was a trend toward lesser contamination in vegans than in omnivores, and olestra had a favourable influence on beta-HCH but did not prevent plasma hyperconcentration of the other OC during ongoing weight loss.
Obesity is increasing in an epidemic manner in most countries and constitutes a public health problem by enhancing the risk for cardiovascular disease and metabolic disorders such as type 2 diabetes. Owing to the increase in obesity, life expectancy may start to decrease in developed countries for the first time in recent history. The factors determining fat mass in adult humans are not fully understood, but increased lipid storage in already developed fat cells (adipocytes) is thought to be most important. Here we show that adipocyte number is a major determinant for the fat mass in adults. However, the number of fat cells stays constant in adulthood in lean and obese individuals, even after marked weight loss, indicating that the number of adipocytes is set during childhood and adolescence. To establish the dynamics within the stable population of adipocytes in adults, we have measured adipocyte turnover by analysing the integration of 14C derived from nuclear bomb tests in genomic DNA. Approximately 10% of fat cells are renewed annually at all adult ages and levels of body mass index. Neither adipocyte death nor generation rate is altered in early onset obesity, suggesting a tight regulation of fat cell number in this condition during adulthood. The high turnover of adipocytes establishes a new therapeutic target for pharmacological intervention in obesity.
The fruits (dates) of the date palm (Phoenix dactylifera L.) contain a high percentage of carbohydrate (total sugars, 44-88%), fat (0.2-0.5%), 15 salts and minerals, protein (2.3-5.6%), vitamins and a high percentage of dietary fibre (6.4-11.5%). The flesh of dates contains 0.2-0.5% oil, whereas the seed contains 7.7-9.7% oil. The weight of the seed is 5.6-14.2% of the date. The fatty acids occur in both flesh and seed as a range of saturated and unsaturated acids, the seeds containing 14 types of fatty acids, but only eight of these fatty acids occur in very low concentration in the flesh. Unsaturated fatty acids include palmitoleic, oleic, linoleic and linolenic acids. The oleic acid content of the seeds varies from 41.1 to 58.8%, which suggests that the seeds of date could be used as a source of oleic acid. There are at least 15 minerals in dates. The percentage of each mineral in dried dates varies from 0.1 to 916 mg/100 g date depending on the type of mineral. In many varieties, potassium can be found at a concentration as high as 0.9% in the flesh while it is as high as 0.5% in some seeds. Other minerals and salts that are found in various proportions include boron, calcium, cobalt, copper, fluorine, iron, magnesium, manganese, potassium, phosphorous, sodium and zinc. Additionally, the seeds contain aluminum, cadmium, chloride, lead and sulphur in various proportions. Dates contain elemental fluorine that is useful in protecting teeth against decay. Selenium, another element believed to help prevent cancer and important in immune function, is also found in dates. The protein in dates contains 23 types of amino acids, some of which are not present in the most popular fruits such as oranges, apples and bananas. Dates contain at least six vitamins including a small amount of vitamin C, and vitamins B(1) thiamine, B(2) riboflavin, nicotinic acid (niacin) and vitamin A. The dietary fibre of 14 varieties of dates has been shown to be as high as 6.4-11.5% depending on variety and degree of ripeness. Dates contain 0.5-3.9% pectin, which may have important health benefits. The world production of dates has increased 2.9 times over 40 years, whereas the world population has doubled. The total world export of dates increased by 1.71% over 40 years. In many ways, dates may be considered as an almost ideal food, providing a wide range of essential nutrients and potential health benefits.
OBJECTIVE: To investigate the effect of replacing lean meat with a soy product, tofu, on coronary heart disease risk factors including serum lipoproteins, lipoprotein (a), factor VII, fibrinogen and in vitro susceptibility of LDL to oxidation. DESIGN: A randomized cross over dietary intervention study. SETTING: Free-living individuals studied at Deakin University. SUBJECTS: Forty-five free-living healthy males aged 35 to 62 years completed the dietary intervention. Three subjects were non-compliant and excluded prior to analysis. INTERVENTIONS: A diet containing 150 grams of lean meat per day was compared to a diet containing 290 grams of tofu per day in an isocaloric and isoprotein substitution. Each dietary period was one month duration. RESULTS: Analysis of the seven-day diet record showed that diets were similar in energy, protein, carbohydrate, total fat, saturated and unsaturated fat, polyunsaturated to saturated fat ratio, alcohol and fiber. Total cholesterol and triglycerides were significantly lower, and in vitro LDL oxidation lag phase was significantly longer on the tofu diet compared to the meat diet. The hemostatic factors, factor VII and fibrinogen, and lipoprotein(a) were not significantly affected by the tofu diet. CONCLUSIONS: The increase in LDL oxidation lag phase would be expected to be associated with a decrease in coronary heart disease risk.
Background: A reduction in dietary saturated fat has generally been thought to improve cardiovascular health. Objective: The objective of this meta-analysis was to summarize the evidence related to the association of dietary saturated fat with risk of coronary heart disease (CHD), stroke, and cardiovascular disease (CVD; CHD inclusive of stroke) in prospective epidemiologic studies. Design: Twenty-one studies identified by searching MEDLINE and EMBASE databases and secondary referencing qualified for inclusion in this study. A random-effects model was used to derive composite relative risk estimates for CHD, stroke, and CVD. Results: During 5–23 y of follow-up of 347,747 subjects, 11,006 developed CHD or stroke. Intake of saturated fat was not associated with an increased risk of CHD, stroke, or CVD. The pooled relative risk estimates that compared extreme quantiles of saturated fat intake were 1.07 (95% CI: 0.96, 1.19; P = 0.22) for CHD, 0.81 (95% CI: 0.62, 1.05; P = 0.11) for stroke, and 1.00 (95% CI: 0.89, 1.11; P = 0.95) for CVD. Consideration of age, sex, and study quality did not change the results. Conclusions: A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD. More data are needed to elucidate whether CVD risks are likely to be influenced by the specific nutrients used to replace saturated fat.
Four out of eight 'healthier' oils-namely, almond oil, avocado oil, hazelnut oil and macadamia nut oil-studied were rich sources of monounsaturated fatty acids like olive oil. Grape seed oil, rice barn oil (marketed recently), toasted sesame oil and walnut oil contained high levels of essential fatty acids. The order of oxidative stability determined by Rancimat measuring of the induction period at four temperatures (90 degrees C, 100 degrees C, 110 degrees C, and 120 degrees C) was found to be macadamia oil > rice bran oil approximately toasted sesame oil > avocado oil > almond oil > hazelnut oil > grape seed oil > walnut oil. High-level monounsaturated fatty acid oils gave a linear relationship between 100 times the reciprocal of the induction period against the total unsaturated fatty acid content obtained as %C18:2 + 0.08 x C18:1 + 2.08 x %C18:3, while the polyunsaturated fatty acid oils gave an exponential relationship. In the case of rice bran and hazelnut oils, shelf-life prediction from the extrapolation of the Arrhenius plots and the Q(10) factors was compared well with that of storage time given by the oil producers. In the cases of the other oils (with an exception of macadamia nut oil), the predicted shelf-lives were significantly lower than that of the storage times; especially, walnut oil (very prone to oxidation) gave 15-20 times lower shelf-life than the best-before storage life.