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1.
Environ Health Prev Med ; 21(6): 430-438, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27312139

RESUMO

OBJECTIVES: Body image in the mass media promotes an unrealistic picture of body shape that leads to body dissatisfaction among adolescentsQuery. Therefore, the study presented in this paper aimed to assess the association between mass media and adolescents' weight concerns and perceptions of body weight and shape. METHODS: A cross-sectional survey was conducted on school adolescents aged between 15 and 18 years during the academic year 2013-2014. Multistage stratified sampling method was used. The number of participants in the study was 795 students: 400 boys and 395 girls. RESULTS: All participants have a common behavior in rarely reading magazines, but they spend more than 2 h in watching television or less than 3 h using the internet. However, most of obese/non-obese adolescents, boys or girls, have shown high influence (p < 0.05) of reading magazines on the subject of dieting to lose weight. CONCLUSION: While obese students read more magazines on dieting to lose weight, other mass media did not show the same results on weight concerns and body shape among Jordanian adolescents.


Assuntos
Imagem Corporal/psicologia , Peso Corporal , Meios de Comunicação de Massa/estatística & dados numéricos , Obesidade/psicologia , Adolescente , Estudos Transversais , Feminino , Humanos , Jordânia/epidemiologia , Masculino , Obesidade/epidemiologia , Obesidade/etiologia , Fatores Sexuais , Estudantes
2.
Curr Opin Clin Nutr Metab Care ; 12(2): 147-51, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19209468

RESUMO

PURPOSE OF REVIEW: To examine experimental evidence that has examined association of phytosterols and the reduction of the risk of cardiovascular disease and cancer. RECENT FINDINGS: Phytosterols exist as naturally occurring plant sterols that are present in the nonsaponifiable fraction of plant oils. Phytosterols are plant components that have a chemical structure similar to cholesterol except for the addition of an extra methyl or ethyl group; however, phytosterol absorption in humans is considerably less than that of cholesterol. In fact, phytosterols reduce cholesterol absorption, although the exact mechanism is not known, and thus reduce circulating levels of cholesterol. The efficacy of phytosterols as cholesterol-lowering agents have been shown when incorporated into fat spreads as well as other food matrices. In addition, phytosterols have been combined with other beneficial dietary components including fish and olive oils, psyllium and beta-glucan to enhance their effect on risk factors of cardiovascular disease. Phytosterols appear not only to play an important role in the regulation of cardiovascular disease but also to exhibit anticancer properties. A side effect associated with the consumption of phytosterols is that they reduce the blood levels of carotenoid. Nevertheless, it has been suggested that compensation for this impact on serum carotenoid levels can occur either by increasing the intake of carotenoid-rich foods or by taking supplements containing these carotenoids. SUMMARY: Dietary phytosterols appear to play an important role in the regulation of serum cholesterol and to exhibit anticancer properties.


Assuntos
Anticolesterolemiantes/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Neoplasias/prevenção & controle , Fitosteróis/uso terapêutico , Anticolesterolemiantes/farmacologia , Carotenoides/metabolismo , Colesterol/sangue , Humanos , Hipercolesterolemia/tratamento farmacológico , Fitosteróis/farmacologia
3.
Curr Atheroscler Rep ; 10(6): 467-72, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18937893

RESUMO

Plant sterols are plant components that have a chemical structure similar to cholesterol except for the addition of an extra methyl or ethyl group; however, plant sterol absorption in humans is considerably less than that of cholesterol. In fact, plant sterols reduce cholesterol absorption and thus reduce circulating levels of cholesterol. Earlier studies that have tested the efficacy of plant sterols as cholesterol-lowering agents incorporated plant sterols into fat spreads. Later on, plant sterols were added to other food matrices, including juices, nonfat beverages, milk and yogurt, cheese, meat, croissants and muffins, and cereal and chocolate bars. The beneficial physiologic effects of plant sterols could be further enhanced by combining them with other beneficial substances, such as olive and fish oils, fibers, and soy proteins, or with exercise. The addition of plant sterols to the diet is suggested by health experts as a safe and effective way to reduce the risk of coronary heart disease.


Assuntos
Anticolesterolemiantes/administração & dosagem , Gorduras na Dieta/administração & dosagem , Fitosteróis/administração & dosagem , Colesterol/sangue , Doença das Coronárias/prevenção & controle , Humanos
4.
Metabolism ; 57(3): 339-46, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18249205

RESUMO

Plant sterols (PSs) reduce plasma total and low-density lipoprotein cholesterol (LDL-C) levels by reducing cholesterol absorption; however, it is not known whether the level of dietary cholesterol intake has an impact on the efficacy of PSs on blood lipids. The purpose of this study was to determine the effect of high vs low dietary cholesterol levels on the lipid-lowering efficacy of free PSs. The study was a semirandomized, double-blind, crossover trial consisting of four 28-day feeding phases each separated by a 4-week washout period. Otherwise healthy hypercholesterolemic subjects (n = 22) consumed each of (a) low-cholesterol control (C(-)S(-)), (b) high-cholesterol control (C(+)S(-)), (c) 22 mg PSs per kilogram of body weight with a low-cholesterol diet (C(-)S(+)), and (d) 22 mg PSs per kilogram of body weight with a high-cholesterol diet (C(+)S(+)). Blood was drawn on the first and last 2 days of each phase to measure plasma total cholesterol, LDL-C, high-density lipoprotein cholesterol, and triacylglycerols as well as plasma campesterol and beta-sitosterol concentrations. Dietary cholesterol had no effect on PS efficacy as a cholesterol-lowering agent because no interaction was found between the 2 factors. However, dietary cholesterol and PS intake had significant independent effects on plasma total cholesterol, LDL-C, and high-density lipoprotein cholesterol levels. beta-Sitosterol levels in plasma increased (P < .0001) as a result of PS supplementation. Data from the present study indicate that, although PSs and dietary cholesterol exert independent effects on plasma cholesterol, PS efficacy is not affected by varying levels of cholesterol intake.


Assuntos
Colesterol na Dieta , Hipercolesterolemia/sangue , Hipercolesterolemia/tratamento farmacológico , Fitosteróis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Peso Corporal/fisiologia , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Cross-Over , Dieta , Método Duplo-Cego , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Pacientes Desistentes do Tratamento , Fitosteróis/sangue , Triglicerídeos/sangue
5.
J Am Coll Nutr ; 27(5): 588-95, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18845709

RESUMO

OBJECTIVE: Plant sterols (PS) consumed as a snack may not have the same cholesterol-lowering potential as when consumed with a meal due to poor solubilization. It was hypothesized that the consumption of a single dose, low-fat yogurt rich in PS (1.6 g/d) with a meal over an afternoon snack will lead to favourable changes in plasma lipids, plasma PS concentrations, and cholesterol synthesis without negatively affecting alpha-tocopherol or carotenoids levels. METHODS: Twenty-six hyperlipidemic males and females completed the randomized trial of three phases (control, single PS dose consumed with a meal, or single PS dose as an afternoon snack) while consuming controlled, low-fat diets. Plasma lipids, cholesterol synthesis rates, plasma PS and serum fat-soluble antioxidants were measured at baseline and after 4 weeks. RESULTS: Endpoint total cholesterol (TC) levels after the PS snack phase were decreased (p = 0.04) (5.30 +/- 0.2 mmol/L) compared to the control phase (5.53 +/- 0.2 mmol/L). However, endpoints for TC (5.37 +/- 0.2 mmol/L) for PS dose with a meal were comparable to control phase. Low-density lipoprotein-cholesterol tended to be different (p = 0.06) at the end of the intervention phases (3.51 +/- 0.1, 3.43 +/- 0.1, and 3.33 +/- 0.1 mmol/L; control, meal and snack, respectively). Cholesterol fractional synthesis rates were higher (p = 0.007) by 25.8% and 19.5% at the end of the snack and meal phases, respectively, compared with the control phase. Plasma campesterol and beta-sitosterol concentrations, adjusted for TC, were higher (p < 0.01) in the snack phase (2.30 +/- 0.3 and 0.54 +/- 0.1 micromol/mmol, respectively) and in the meal phase (2.00 +/- 0.3 and 0.51 +/- 0.1 micromol/mmol, respectively) when compared to the control phase (1.81 +/- 0.3 and 0.40 +/- 0.1 micromol/mmol, respectively). No changes in alpha-tocopherol or carotenoids levels were detected after adjusting for TC, for all phases. CONCLUSION: These results indicate that a single dose of PS in low-fat yogurt, provided as a snack, lowers cholesterol levels but does not alter fat-soluble vitamin or carotenoid concentrations in hyperlipidemic participants.


Assuntos
Colesterol/biossíntese , Hiperlipidemias/dietoterapia , Fitosteróis/administração & dosagem , Iogurte , Adulto , Idoso , Idoso de 80 Anos ou mais , Carotenoides/sangue , Colesterol/sangue , Estudos Cross-Over , Dieta , Feminino , Alimentos Fortificados , Humanos , Hiperlipidemias/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Vitaminas/sangue
6.
Lipids ; 53(9): 897-908, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30407633

RESUMO

The triacylglycerol (TAG)-lowering effects of long-chain n-3 fatty acids, and in particular docosahexaenoic acid (DHA), are well documented, although these effects manifest large interindividual variability. The objective of this secondary analysis is to investigate whether common single-nucleotide polymorphisms (SNP) in genes involved in DHA synthesis and TAG metabolism are associated with the responsiveness of blood lipids, lipoprotein, and apolipoprotein concentration to dietary treatment by DHA supplied in high-oleic canola oil (HOCO). In a randomized, crossover-controlled feeding trial, 129 subjects with metabolic syndrome received high-oleic canola oil (HOCO) and high-oleic canola oil supplemented with DHA (HOCO-DHA), each for 4 weeks. During the HOCO-DHA phase, the intake of DHA ranged from 1 to 2.5 g/day. The subjects were genotyped for apolipoprotein E (APOE) isoforms, and SNP including FADS1-rs174561, FADS2-rs174583, ELOVL2-rs953413, ELOVL5-rs2397142, CETP-rs5882, SCD1-rs2234970, PPARA-rs6008259, and LIPF-rs814628 were selected as important genes controlling fatty acid metabolism. Overall, consumption of HOCO-DHA oil reduced blood concentrations of TAG by 24% compared to HOCO oil. The reduction in TAG was independent of genetic variations in the studied genes. Similarly, no treatment-by-gene interactions were evident in the response to other lipids, lipoproteins, or apolipoproteins to DHA supplementation. Nevertheless, a lower interindividual variation in the TAG response to DHA supplementation compared to other studies was observed in this analysis. The TAG-lowering effect of a supplemental body-weight-based dose of DHA was not influenced by genetic variations in APOE, FADS1, FADS2, ELOVL2, ELOVL5, CETP, SCD1, PPARA, and LIPF.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único/genética , Triglicerídeos/farmacologia , Estudos Cross-Over , Dessaturase de Ácido Graxo Delta-5 , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue , Triglicerídeos/metabolismo
7.
Clin Nutr ; 36(3): 848-852, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27206698

RESUMO

BACKGROUND & AIMS: Dietary pattern and lifestyle have been reported to be important risk factors in the development of colorectal cancer (CRC). However, the mechanism of action of dietary factors in CRC disease is unclear. The aim of this study is the examination of several dietary choices and their potential association with the risk of developing CRC. METHODS: Dietary data was collected from 220 subjects who were previously diagnosed with CRC, and 281 control subjects (matched by age, gender, occupation and marital status). The data was collected between January 2010 and December 2012, using interview-based questionnaires. Multivariate logistic regression was used to estimate the relationship between dietary choices and risk of developing colorectal cancer. RESULTS: Factor analysis revealed three major dietary patterns. The first pattern we identified as the "Healthy Pattern", the second was identified as "High Sugar/High Tea Pattern" and the third as "Western Pattern". In the Healthy Pattern group we found a 10.54% variation in food intake, while the intake variation was 11.64% in the Western Pattern. After adjusting for confounding factors, the Western Pattern food choice was found to be significantly associated with an increased risk of developing CRC (OR = 1.88; 95% CI = 1.12-3.16). The results for the Healthy and High-Sugar/High Tea Patterns showed a decrease, but the statistic was not significant for the risk of CRC development. CONCLUSION: The Western Pattern of dietary choice was directly associated with CRC. The association between the dietary food choice in the Healthy and High-Sugar/High Tea Patterns and colorectal cancer needs further study in our Jordanian population.


Assuntos
Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Dieta , Adulto , Estudos de Casos e Controles , Comportamento de Escolha , Dieta Ocidental/efeitos adversos , Exercício Físico , Feminino , Preferências Alimentares , Comportamentos Relacionados com a Saúde , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Análise de Componente Principal , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários
8.
Lipids Health Dis ; 3: 5, 2004 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-15070410

RESUMO

Plant sterols are naturally occurring molecules that humanity has evolved with. Herein, we have critically evaluated recent literature pertaining to the myriad of factors affecting efficacy and safety of plant sterols in free and esterified forms. We conclude that properly solubilized 4-desmetyl plant sterols, in ester or free form, in reasonable doses (0.8-1.0 g of equivalents per day) and in various vehicles including natural sources, and as part of a healthy diet and lifestyle, are important dietary components for lowering low density lipoprotein (LDL) cholesterol and maintaining good heart health. In addition to their cholesterol lowering properties, plant sterols possess anti-cancer, anti-inflammatory, anti-atherogenicity, and anti-oxidation activities, and should thus be of clinical importance, even for those individuals without elevated LDL cholesterol. The carotenoid lowering effect of plant sterols should be corrected by increasing intake of food that is rich in carotenoids. In pregnant and lactating women and children, further study is needed to verify the dose required to decrease blood cholesterol without affecting fat-soluble vitamins and carotenoid status.

9.
Can J Cardiol ; 30(10): 1225-32, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25262863

RESUMO

More than 200 clinical trial reports and several meta-analyses have demonstrated that phytosterols (PSs), natural components of plants, induce clinically relevant reductions in blood low-density lipoprotein cholesterol levels. Here we review data regarding the biochemical effects and potential cardiovascular benefit of PSs as part of the dietary management of dyslipidemia. In addition to discussing the efficacy, effectiveness, and safety of PSs as hypocholesterolemic agents, this review provides an overview of PSs as an adjunctive therapy to cholesterol-lowering pharmaceuticals. Given this lack of evidence regarding the benefits of PSs for reducing cardiovascular end points, this review also discusses the present knowledge that exists about the ability for therapeutic dosages of PSs to confer protection from cardiovascular-related mortality and morbidity. Finally, this review summarizes the factors that affect PS efficacy and the Canadian regulations that govern the use of PSs as cholesterol-lowering agents in foods and supplements.


Assuntos
Anticolesterolemiantes/uso terapêutico , Dislipidemias/tratamento farmacológico , Fitosteróis/uso terapêutico , Azetidinas/uso terapêutico , Suplementos Nutricionais , Ezetimiba , Humanos , Fitosteróis/metabolismo , Resultado do Tratamento
10.
J Acad Nutr Diet ; 113(11): 1494-1503, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24144075

RESUMO

Plant sterols/stanols-enriched foods possess well-documented low-density lipoprotein (LDL)-cholesterol-lowering effect. However, the relative efficacy of plant sterols/stanols as supplements (tablets/capsules) compared with other dietary forms still needs to be determined. Our aim was to precisely identify and quantify the LDL-cholesterol-lowering effect of plant sterols/stanols as supplements in contrast to food-based approaches. Eight eligible clinical trials published from January 1992 to April 2013 were identified from five databases. A random effect model was used to calculate weighted mean effect sizes for net differences in LDL-cholesterol concentrations. Among the included trials with the duration between 4 and 6 weeks, plant sterol/stanol dose ranged from 1.0 to 3.0 g/day administrated mainly with the main meals (2 or 3 times/day). Intake of plant sterol/stanol supplements decreased LDL-cholesterol concentrations by 12 mg/dL (0.31 mmol/L) (95% CI -0.39 to -0.23; P<0.000) compared with placebo. The test of heterogeneity was not significant (χ(2) , P=0.50, I(2)=0%). Further analysis showed no significant difference between the LDL-cholesterol-lowering action of plant sterols/stanols supplements (-12 mg/dL [-0.31 mmol/L]; 95% CI -0.39 to -0.24; P<0.0001) vs foods enriched with plant sterols/stanols (-12 mg/dL [-0.31 mmol/L]; 95% CI -0.35 to -0.27; P<0.0001). Plant sterol/stanol supplements as part of a healthy diet represent an effective means of delivering LDL-cholesterol-lowering similar to plant sterols/stanols delivered in various food formats.


Assuntos
Anticolesterolemiantes/administração & dosagem , Suplementos Nutricionais , Fitosteróis/administração & dosagem , LDL-Colesterol/sangue , Dieta , Humanos , MEDLINE , Reprodutibilidade dos Testes
11.
Nutr Rev ; 68(8): 485-99, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20646226

RESUMO

Randomized clinical trial data are capable of providing strong experimental evidence to establish causal relationships between functional food components and health and disease/disease risk. However, clinical studies must be well designed in order to optimize the quality of the data they provide. The purpose of this review is to identify design elements that maximize the quality of clinical trials examining the efficacy of functional foods. Both observational studies and experimental trials can provide useful data for identifying diet-disease relationships. Two experimental designs are conventionally used: parallel and crossover. Each of these designs possesses advantages and disadvantages. For certain functional ingredients, selection of an appropriate control arm is straightforward, while for others it is challenging. Studies should be short enough to optimize subject compliance, be cost effective, and avoid high subject dropout rates, while being lengthy enough to ensure biological efficacy. The dose, frequency, and diurnal timing of intake of the active food ingredient all need to be chosen carefully. Randomized clinical trials testing the efficacy of functional foods may use both validated and emerging surrogate endpoints and should employ suitable statistical tests for data analysis. Paying attention to all these factors is crucial to the design of quality clinical trials that reliably evaluate food-health relationship validity. Accordingly, clinical studies that incorporate the optimal design elements discussed will yield robust results appropriate for the substantiation of health claims on functional foods.


Assuntos
Alimento Funcional/normas , Fenômenos Fisiológicos da Nutrição/fisiologia , Projetos de Pesquisa , Análise Custo-Benefício , Medicina Baseada em Evidências , Alimento Funcional/economia , Humanos , Resultado do Tratamento
12.
Am J Clin Nutr ; 92(1): 41-6, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20444957

RESUMO

BACKGROUND: The cholesterol-lowering effectiveness of plant sterol (PS) therapy is hindered by wide-ranging variability in LDL-cholesterol responsiveness across individuals. To capitalize on the LDL-cholesterol-lowering potential of PS in the clinical setting, it is paramount to characterize the metabolic factors that underlie this heterogeneity of responsiveness. OBJECTIVE: The objective was to investigate the relation between cholesterol synthesis and plasma LDL-cholesterol reductions in response to PS consumption. DESIGN: We evaluated previously conducted clinical PS interventions incorporating stable-isotope measures of cholesterol synthesis and conducted feeding studies in animal models of response (Syrian Golden hamsters) and nonresponse (C57BL/6J mice) to PS consumption. RESULTS: From our clinical study population (n = 113), we identified 47 nonresponders (3.73 +/- 1.10% change in LDL cholesterol) and 66 responders (-15.16 +/- 1.04% change in LDL cholesterol) to PS therapy. The basal cholesterol fractional synthesis rate (FSR) as measured by direct deuterium incorporation was 23% higher (P = 0.003) in the nonresponder subgroup than in responders to PS therapy. The basal cholesterol FSR correlated (r = 0.22, P = 0.02) with the percentage change in LDL cholesterol after PS intervention. In support of our clinical observations, nonresponding mice showed a 77% higher (P = 0.001) basal cholesterol FSR than that of responding hamsters. Compared with control mice, PS-fed mice showed an increase in hepatic nuclear sterol regulatory element binding protein 2 abundance (1.3-fold of control, P = 0.04) and beta-hydroxy-beta-methylglutaryl coenzyme A reductase-mRNA expression (2.4-fold of control, P = 0.00). CONCLUSION: The results suggest that subjects with high basal cholesterol synthesis are less responsive to PS treatment than are subjects with low basal cholesterol synthesis.


Assuntos
LDL-Colesterol/sangue , Colesterol/biossíntese , Colesterol/sangue , Fitosteróis/uso terapêutico , Adulto , Animais , HDL-Colesterol/sangue , LDL-Colesterol/efeitos dos fármacos , Cricetinae , Estudos Cross-Over , Feminino , Humanos , Fígado/metabolismo , Masculino , Mesocricetus , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Fitosteróis/farmacologia , RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triglicerídeos/sangue
13.
J Med Food ; 12(5): 925-34, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19857053

RESUMO

The evolution of the human diet over the past 10,000 years from a Paleolithic diet to our current modern pattern of intake has resulted in profound changes in feeding behavior. Shifts have occurred from diets high in fruits, vegetables, lean meats, and seafood to processed foods high in sodium and hydrogenated fats and low in fiber. These dietary changes have adversely affected dietary parameters known to be related to health, resulting in an increase in obesity and chronic disease, including cardiovascular disease (CVD), diabetes, and cancer. Some intervention trials using Paleolithic dietary patterns have shown promising results with favorable changes in CVD and diabetes risk factors. However, such benefits may be offset by disadvantages of the Paleolithic diet, which is low in vitamin D and calcium and high in fish potentially containing environmental toxins. More advantageous would be promotion of foods and food ingredients from our ancestral era that have been shown to possess health benefits in the form of functional foods. Many studies have investigated the health benefits of various functional food ingredients, including omega-3 fatty acids, polyphenols, fiber, and plant sterols. These bioactive compounds may help to prevent and reduce incidence of chronic diseases, which in turn could lead to health cost savings ranging from $2 to $3 billion per year as estimated by case studies using omega-3 and plant sterols as examples. Thus, public health benefits should result from promotion of the positive components of Paleolithic diets as functional foods.


Assuntos
Doença Crônica/prevenção & controle , Dieta , Alimento Funcional , Dieta/história , História Antiga , Humanos
14.
Food Nutr Res ; 522008.
Artigo em Inglês | MEDLINE | ID: mdl-19109655

RESUMO

BACKGROUND: Consumption of plant sterols has been reported to reduce low density lipoprotein (LDL) cholesterol concentrations by 5-15%. Factors that affect plant sterol efficacy are still to be determined. OBJECTIVES: To more precisely quantify the effect of plant sterol enriched products on LDL cholesterol concentrations than what is reported previously, and to identify and quantify the effects of subjects' characteristics, food carrier, frequency and time of intake on efficacy of plant sterols as cholesterol lowering agents. DESIGN: Fifty-nine eligible randomized clinical trials published from 1992 to 2006 were identified from five databases. Weighted mean effect sizes were calculated for net differences in LDL levels using a random effect model. RESULTS: Plant sterol containing products decreased LDL levels by 0.31 mmol/L (95% CI, -0.35 to -0.27, P= < 0.0001) compared with placebo. Between trial heterogeneity was evident (Chi-square test, P = <0.0001) indicating that the observed differences between trial results were unlikely to have been caused by chance. Reductions in LDL levels were greater in individuals with high baseline LDL levels compared with those with normal to borderline baseline LDL levels. Reductions in LDL were greater when plant sterols were incorporated into fat spreads, mayonnaise and salad dressing, milk and yoghurt comparing with other food products such as croissants and muffins, orange juice, non-fat beverages, cereal bars, and chocolate. Plant sterols consumed as a single morning dose did not have a significant effect on LDL cholesterol levels. CONCLUSION: Plant sterol containing products reduced LDL concentrations but the reduction was related to individuals' baseline LDL levels, food carrier, and frequency and time of intake.

15.
Appl Physiol Nutr Metab ; 33(4): 728-34, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18641716

RESUMO

Plant sterol (PS) consumption decreases low-density lipoprotein cholesterol (LDL-C) levels; however, high variability of responsiveness of lipid levels to PS intervention has been observed. We hypothesized that common single-nucleotide polymorphisms (SNPs) in the genes for the ATP binding cassette proteins G5 (ABCG5) and G8 (ABCG8), Niemann-Pick C1-like 1 (NPC1L1), or other proteins of the cholesterol pathway, would underline inter-individual variations in response to PS. Twenty-six hyperlipidemic subjects completed a randomized trial of 3 PS phases and a control phase. Three non-responders were identified who failed on 3 consecutive occasions to decrease either total cholesterol or LDL-C level vs. control. It was observed that after 3 PS phases compared with a control phase, cholesterol absorption changed to a lesser degree (-7.7% +/- 10.8%) in the non-responders than in the top 3 responders (-22.1% +/- 8.8%); however, cholesterol synthesis rates did not differ between sub-groups. No common polymorphisms in ABCG8, ABCG5, or NPC1L1 were demonstrated between the 3 top responders and the non-responders. Yet, 1 non-responsive subject did demonstrate a rare SNP in NPC1L1. Results indicate PS intake did not decrease cholesterol absorption rates to the same degree in certain subjects, possibly clarifying the inter-individual variability in the cholesterol-lowering effect; hence, this work should be expanded.


Assuntos
Colesterol/genética , Colesterol/metabolismo , Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Fitosteróis/farmacologia , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Colesterol/sangue , Estudos Cross-Over , Feminino , Humanos , Hiperlipidemias/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Fitosteróis/sangue , Reação em Cadeia da Polimerase , Método Simples-Cego
16.
J Nutr ; 136(4): 1012-6, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16549466

RESUMO

Recommendations for decreasing the risk of developing cardiovascular disease include increasing the intake of plant sterols and fish oil. The cholesterol-lowering action of plant sterols, when provided in a fish-oil fatty acids vehicle, remains to be investigated in humans. A randomized, crossover-feeding, single-blind trial was conducted in 30 subjects with mild-to-moderate hypercholesterolemia to study the effects on plasma lipids of 2 novel forms of plant sterols: those combined with, or esterified to, fish-oil fatty acids. The treatments were margarine (control), free plant sterols, plant sterols esterified to fatty acids from sunflower oil, plant sterols esterified to very long-chained fatty acids from fish oil, and plant sterols combined with the same amount of very long-chained fatty acids from fish oil. Each sterol-containing food (1.0-1.8 g plant sterols/d) was consumed for 29 d as a single dose with breakfast under staff supervision. Compared with the control treatment, none of the plant sterol preparations reduced plasma total cholesterol or LDL cholesterol, triacylglycerol, apolipoprotein A-I, apolipoprotein B, lipoprotein (a), or C-reactive protein concentration. Relative to the control phase, all plant sterols treatment increased the plasma HDL cholesterol concentration (P < 0.05) by approximately 8%. In conclusion, because standard forms of plant sterols did not reduce plasma cholesterol concentrations, the efficacy of the new formulation of plant sterols cannot be confirmed from the present study design, where plant sterols were given as a single morning dose.


Assuntos
Dieta , Óleos de Peixe/administração & dosagem , Hipercolesterolemia/tratamento farmacológico , Lipídeos/sangue , Fitosteróis/administração & dosagem , Idoso , Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , Proteína C-Reativa/análise , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Cross-Over , Esterificação , Ácidos Graxos/administração & dosagem , Ácidos Graxos/química , Feminino , Humanos , Hipercolesterolemia/sangue , Lipoproteína(a)/sangue , Masculino , Pessoa de Meia-Idade , Fitosteróis/química , Óleos de Plantas/química , Óleo de Girassol
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