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1.
Crit Rev Food Sci Nutr ; 62(21): 5824-5885, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33775173

RESUMO

Soybeans are a rich source of isoflavones, which are classified as phytoestrogens. Despite numerous proposed benefits, isoflavones are often classified as endocrine disruptors, based primarily on animal studies. However, there are ample human data regarding the health effects of isoflavones. We conducted a technical review, systematically searching Medline, EMBASE, and the Cochrane Library (from inception through January 2021). We included clinical studies, observational studies, and systematic reviews and meta-analyses (SRMA) that examined the relationship between soy and/or isoflavone intake and endocrine-related endpoints. 417 reports (229 observational studies, 157 clinical studies and 32 SRMAs) met our eligibility criteria. The available evidence indicates that isoflavone intake does not adversely affect thyroid function. Adverse effects are also not seen on breast or endometrial tissue or estrogen levels in women, or testosterone or estrogen levels, or sperm or semen parameters in men. Although menstrual cycle length may be slightly increased, ovulation is not prevented. Limited insight could be gained about possible impacts of in utero isoflavone exposure, but the existing data are reassuring. Adverse effects of isoflavone intake were not identified in children, but limited research has been conducted. After extensive review, the evidence does not support classifying isoflavones as endocrine disruptors.


Assuntos
Disruptores Endócrinos , Isoflavonas , Estudos Clínicos como Assunto , Estrogênios , Feminino , Humanos , Isoflavonas/efeitos adversos , Isoflavonas/farmacologia , Masculino , Estudos Observacionais como Assunto , Glycine max
2.
J Nutr ; 149(4): 619-627, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30926986

RESUMO

BACKGROUND: Consumption of green tea has been associated with reduced risk of breast cancer. Hormonal modulation has been suggested as one of the potential underlying mechanisms; however, it has yet to be fully elucidated in large, long-term human clinical trials. OBJECTIVE: We investigated the effects of decaffeinated green tea extract (GTE) on circulating sex hormones and insulin-like growth factor (IGF) proteins. METHODS: We conducted a placebo-controlled double-blind randomized clinical trial recruiting from 8 clinical centers in Minnesota. Participants were 538 healthy postmenopausal women randomly assigned to the GTE group (463 completed the study; mean age = 60.0 y) and 537 to the placebo group (474 completed; mean age = 59.7 y). Women in the GTE group orally took 4 decaffeinated capsules containing 1315 mg total catechins including 843 mg epigallocatechin-3-gallate daily for 1 y, whereas women in the placebo group took similar capsules containing no tea catechins. Blood sex hormones (estrone, estradiol, androstenedione, testosterone, and sex hormone-binding globulin) and IGF proteins (IGF-1 and IGF binding protein-3) were quantified at baseline and months 6 (for IGF proteins only) and 12, and were assessed as secondary outcomes of the study using a mixed-effect repeated-measures ANOVA model. RESULTS: Women in the GTE group had significantly higher blood total estradiol (16%; P = 0.02) and bioavailable estradiol (21%; P = 0.03) than in the placebo group at month 12. There was a statistically significant interaction between GTE supplementation and duration of treatment on estradiol and bioavailable estradiol (both Ps for interaction = 0.001). The catechol-O-methyltransferase genotype did not influence blood sex hormones before or after GTE supplementation. The circulating concentrations of IGF proteins were comparable between GTE and placebo groups at all 3 time points. CONCLUSION: These results suggest that a 12-mo GTE supplementation significantly increases circulating estradiol concentrations in healthy postmenopausal women. This trial was registered at clinicaltrials.gov as NCT00917735.


Assuntos
Neoplasias da Mama , Catequina/farmacologia , Hormônios Esteroides Gonadais/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Extratos Vegetais/farmacologia , Chá/química , Idoso , Catequina/química , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Extratos Vegetais/química , Pós-Menopausa
3.
J Nutr ; 147(9): 1693-1699, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28747487

RESUMO

Background: Dietary factors, such as antioxidant nutrients, contribute significantly to the maintenance of an appropriate balance between antioxidant defense and free radical production in the body.Objective: The objective of this study was to examine the relation between oxidative stress as assessed by plasma F2-isoprostane (IsoP) concentration, glycemic load (GL), glycemic index (GI), intake of antioxidant nutrients, dietary fiber, and polyunsaturated fatty acids (PUFAs).Methods: This study was a cross-sectional secondary analysis of baseline data collected from a random sample of 269 postmenopausal women participating in the Minnesota Green Tea Trial. GL, GI, and dietary variables were calculated from the diet history questionnaire. Subjects filled out surveys about the use of anti-inflammatory drugs and physical activity. Plasma IsoP concentration was assessed by GC-mass spectrometry. IsoP concentrations were compared across quartiles of GL, GI, insoluble fiber, PUFAs, and antioxidant nutrients with the use of linear regression.Results: Antioxidant supplement intake, including zinc, copper, vitamin C and vitamin E, was reported by >60% of the participants. Mean intake of PUFAs was 12.5 g. Mean plasma IsoP concentrations increased from 34 to 36.7 pg/mL in the lowest quartiles of GL and GI, respectively, to 45.2 and 41.6 pg/mL, respectively, in the highest quartiles (P-trend = 0.0014 for GL and P-trend = 0.0379 for GI), whereas mean IsoP concentrations decreased from 41.8 pg/mL in the lowest quartile of PUFAs to 34.9 pg/mL in the highest quartile (P-trend = 0.0416). Similarly, mean IsoP concentrations decreased from 44.4 pg/mL in the lowest quartile of insoluble fiber to 36 pg/mL in the highest quartile (P-trend = 0.0243) after adjustment for potential confounders.Conclusions: We concluded that dietary PUFAs and insoluble fiber are inversely associated with oxidative stress whereas GL and GI are positively associated with oxidative stress in postmenopausal women. This trial was registered at clinicaltrials.gov as NCT00917735.


Assuntos
Dieta , Fibras na Dieta/farmacologia , F2-Isoprostanos/sangue , Ácidos Graxos Insaturados/farmacologia , Índice Glicêmico , Carga Glicêmica , Estresse Oxidativo , Antioxidantes/administração & dosagem , Estudos Transversais , Gorduras Insaturadas na Dieta/farmacologia , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Inquéritos e Questionários
4.
J Nutr ; 146(2): 256-64, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26701796

RESUMO

BACKGROUND: Green tea extract (GTE) consumption has been linked to favorable changes in adiposity and bone mineral density (BMD), although it is unknown if these effects are due to green tea catechins or caffeine. The catechol-O-methyltransferase (COMT) genotype may also modify these associations. OBJECTIVE: We examined the impact of decaffeinated GTE on body composition (using dual-energy X-ray absorptiometry) and obesity-associated hormones. METHODS: The Minnesota Green Tea Trial was a 12-mo randomized, double-blind, placebo-controlled clinical trial in 937 postmenopausal women (aged 50-70 y) assigned to receive either GTE containing 843 mg (-)-epigallocatechin-3-gallate or placebo. This substudy was conducted in 121 overweight/obese participants [body mass index (BMI) (kg/m(2)) ≥25.0]. RESULTS: There were no differences in changes in BMI (-0.13 ± 0.11 compared with -0.05 ± 0.11; P = 0.61), total fat mass (-0.30 ± 0.16 compared with -0.12 ± 0.15 kg; P = 0.40), percentage of body fat (-0.15% ± 0.17% compared with -0.15% ± 0.16%; P = 0.99), or BMD (-0.006 ± 0.002 compared with -0.003 ± 0.002 g/cm(2); P = 0.49) over 12 mo between women taking GTE (n = 61) and those taking a placebo (n = 60). Interactions were observed between treatment and time for gynoid percentage of fat (%fat) and tissue %fat. Gynoid %fat increased from baseline to month 12 in the placebo group as baseline BMI increased and decreased over time as baseline BMI increased in the GTE group (P-interaction = 0.02). Tissue %fat increased from baseline to month 12 in the placebo group as baseline BMI increased. In the GTE group, tissue %fat decreased during the intervention as baseline BMI increased (P-interaction = 0.04). No changes were seen in circulating leptin, ghrelin, adiponectin, or insulin concentrations. COMT genotype did not modify the effect of GTE on any variable. CONCLUSIONS: Decaffeinated GTE was not associated with overall reductions in adiposity or improvements in BMD in overweight/obese postmenopausal women. However, GTE may be beneficial for reduction in tissue and gynoid %fat in individuals with higher BMI. This clinical trial was registered at www.clinicaltrials.gov as NCT00917735.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Composição Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Camellia sinensis/química , Suplementos Nutricionais , Obesidade/metabolismo , Extratos Vegetais/farmacologia , Tecido Adiposo/metabolismo , Adiposidade/efeitos dos fármacos , Índice de Massa Corporal , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Cafeína/farmacologia , Camellia sinensis/genética , Catequina/análogos & derivados , Catequina/farmacologia , Catecol O-Metiltransferase/genética , Método Duplo-Cego , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Obesidade/tratamento farmacológico , Sobrepeso , Pós-Menopausa , Chá/química
5.
J Nutr ; 146(1): 38-45, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26581683

RESUMO

BACKGROUND: Green tea consumption has been associated with favorable changes in body weight and obesity-related hormones, although it is not known whether these changes result from green tea polyphenols or caffeine. OBJECTIVE: We examined the impact of decaffeinated green tea extract (GTE) containing 843 mg of (-)-epigallocatechin-3-gallate on anthropometric variables, obesity-associated hormones, and glucose homeostasis. METHODS: The Minnesota Green Tea Trial was a 12-mo randomized, double-blind, placebo-controlled clinical trial of 937 healthy postmenopausal women assigned to either decaffeinated GTE (1315 mg total catechins/d) or a placebo, stratified by catechol-O-methyltransferase (COMT) genotype. This study was conducted in a subset of 237 overweight and obese participants [body mass index (BMI) ≥25 kg/m(2)]. RESULTS: No changes in energy intake, body weight, BMI, or waist circumference (WC) were observed over 12 mo in women taking GTE (n = 117) or placebo (n = 120). No differences were seen in circulating leptin, ghrelin, adiponectin, or glucose concentrations at month 12. Participants randomly assigned to GTE with baseline insulin ≥10 µIU/mL (n = 23) had a decrease in fasting serum insulin from baseline to month 12 (-1.43 ± 0.59 µIU/mL), whereas those randomly assigned to placebo with baseline insulin ≥10 µIU/mL (n = 19) had an increase in insulin over 12 mo (0.55 ± 0.64 µIU/mL, P < 0.01). Participants with the homozygous high-activity (G/G) form of COMT had significantly lower adiponectin (5.97 ± 0.50 compared with 7.58 ± 0.53 µg/mL, P = 0.03) and greater insulin concentrations (7.63 ± 0.53 compared with 6.18 ± 0.36 µIU/mL, P = 0.02) at month 12 compared with those with the low-activity (A/A) genotype, regardless of treatment group. CONCLUSIONS: Decaffeinated GTE was not associated with reductions in body weight, BMI, or WC and did not alter energy intake or mean hormone concentrations in healthy postmenopausal women over 12 mo. GTE decreased fasting insulin concentrations in those with elevated baseline fasting concentrations. The high-activity form of the COMT enzyme may be associated with elevations in insulin and a reduction in adiponectin concentrations over time. This trial was registered at http://www.clinicaltrials.gov as NCT00917735.


Assuntos
Adiponectina/sangue , Catecol O-Metiltransferase/genética , Insulina/sangue , Obesidade/sangue , Sobrepeso/sangue , Chá/química , Administração Oral , Idoso , Glicemia/metabolismo , Índice de Massa Corporal , Peso Corporal , Cafeína/administração & dosagem , Cafeína/análise , Catequina/administração & dosagem , Catequina/análogos & derivados , Método Duplo-Cego , Ingestão de Energia , Jejum , Feminino , Genótipo , Grelina/sangue , Humanos , Leptina/sangue , Pessoa de Meia-Idade , Atividade Motora , Avaliação Nutricional , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem , Pós-Menopausa , Circunferência da Cintura
6.
Ecol Food Nutr ; 55(1): 87-109, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26654593

RESUMO

Nutritional and body weight recommendations for cardiovascular diseases are well established, yet there are no equivalent guidelines for peripheral arterial disease (PAD). This cross-sectional study measured the prevalence of cardiovascular-related nutritional and body composition risk factors in sixty PAD patients and their association with PAD severity. A diet that exceeds daily recommended intake of fat and that falls short of recommended intakes of fiber, folate, and vitamin D was associated with increased leg pain and walking difficulty. Increased body fat and waist circumference were associated with diminished walking ability and poorer psychosocial quality of life. Future prospective investigations are merited to inform both PAD clinical care and disease management guidelines.


Assuntos
Composição Corporal , Dieta , Estado Nutricional , Dor , Doença Arterial Periférica , Qualidade de Vida , Índice de Gravidade de Doença , Tecido Adiposo , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Estudos Transversais , Comportamento Alimentar , Feminino , Humanos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Doença Arterial Periférica/complicações , Doença Arterial Periférica/psicologia , Qualidade de Vida/psicologia , Fatores de Risco , Vitaminas/administração & dosagem , Vitaminas/metabolismo , Circunferência da Cintura , Caminhada
7.
Breast Cancer Res Treat ; 154(2): 309-18, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26510851

RESUMO

UNLABELLED: Medical and surgical interventions for elevated breast cancer risk (e.g., BRCA1/2 mutation, family history) focus on reducing estrogen exposure. Women at elevated risk may be interested in less aggressive approaches to risk reduction. For example, exercise might reduce estrogen, yet has fewer serious side effects and less negative impact than surgery or hormonal medications. Randomized controlled trial. Increased risk defined by risk prediction models or BRCA mutation status. Eligibility: Age 18-50, eumenorrheic, non-smokers, and body mass index (BMI) between 21 and 50 kg/m(2). 139 were randomized. Treadmill exercise: 150 or 300 min/week, five menstrual cycles. Control group maintained exercise <75 min/week. PRIMARY OUTCOME: Area under curve (AUC) for urinary estrogen. Secondary measures: urinary progesterone, quantitative digitized breast dynamic contrast-enhanced magnetic resonance imaging background parenchymal enhancement. Mean age 34 years, mean BMI 26.8 kg/m(2). A linear dose-response relationship was observed such that every 100 min of exercise is associated with 3.6 % lower follicular phase estrogen AUC (linear trend test, p = 0.03). No changes in luteal phase estrogen or progesterone levels. There was also a dose-response effect noted: for every 100 min of exercise, there was a 9.7 % decrease in background parenchymal enhancement as measured by imaging (linear trend test, p = 0.009). Linear dose-response effect observed to reduce follicular phase estrogen exposure measured via urine and hormone sensitive breast tissue as measured by imaging. Future research should explore maintenance of effects and extent to which findings are repeatable in lower risk women. Given the high benefit to risk ratio, clinicians can inform young women at increased risk that exercise may blunt estrogen exposure while considering whether to try other preventive therapies.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/urina , Estrogênios/urina , Exercício Físico , Adulto , Biomarcadores , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Pré-Menopausa , Progesterona/urina , Medição de Risco , Fatores de Risco
8.
Cancer Causes Control ; 26(10): 1405-19, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26206423

RESUMO

PURPOSE: The Minnesota Green Tea Trial (MGTT) was a randomized, placebo-controlled, double-blinded trial investigating the effect of daily green tea extract consumption for 12 months on biomarkers of breast cancer risk. METHODS: Participants were healthy postmenopausal women at high risk of breast cancer due to dense breast tissue with differing catechol-O-methyltransferase (COMT) genotypes. The intervention was a green tea catechin extract containing 843.0 ± 44.0 mg/day epigallocatechin gallate or placebo capsules for 1 year. Annual digital screening mammograms were obtained at baseline and month 12, and fasting blood and 24-h urine samples were provided at baseline and at months 6 and 12. Primary endpoints included changes in percent mammographic density, circulating endogenous sex hormones, and insulin-like growth factor axis proteins; secondary endpoints were changes in urinary estrogens and estrogen metabolites and circulating F2-isoprostanes, a biomarker of oxidative stress. RESULTS: The MGTT screened more than 100,000 mammograms and randomized 1,075 participants based on treatment (green tea extract vs. placebo), stratified by COMT genotype activity (high COMT vs. low/intermediate COMT genotype activity). A total of 937 women successfully completed the study and 138 dropped out (overall dropout rate = 12.8 %). CONCLUSIONS: In this paper we report the rationale, design, recruitment, participant characteristics, and methods for biomarker and statistical analyses.


Assuntos
Biomarcadores/metabolismo , Neoplasias da Mama/prevenção & controle , Mama/anatomia & histologia , Mamografia , Chá , Antioxidantes/administração & dosagem , Catequina/administração & dosagem , Catequina/análogos & derivados , Catecol O-Metiltransferase/genética , Método Duplo-Cego , Estrogênios/urina , F2-Isoprostanos/sangue , Feminino , Genótipo , Hormônios Esteroides Gonadais/sangue , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Pessoa de Meia-Idade , Minnesota , Estresse Oxidativo , Fatores de Risco
9.
J Diet Suppl ; 20(6): 850-869, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36178169

RESUMO

The predominant catechin in green tea, epigallocatechin gallate (EGCG), may be hepatotoxic in high doses. Our objective was to investigate the influence of catechol-O-methyltransferase (COMT) and uridine 5'-diphospho-glucuronosyltransferase 1A4 (UGT1A4) genotypes on changes in liver injury biomarkers in response to long-term, high-dose green tea extract (GTE) supplementation among postmenopausal women. A secondary analysis was conducted using data from the Minnesota Green Tea Trial (N = 1,075), in which participants were randomized to consume high-dose GTE (843 mg/day EGCG) or placebo capsules for 12 months. Analysis of covariance adjusting for potential confounders was performed to examine changes in aspartate aminotransferase (AST), alanine aminotransferase (ALT), AST: ALT ratio, and alkaline phosphatase from baseline to months 3, 6, 9, and 12 across COMT and UGT1A4 genotypes. Mean age and BMI within the GTE group (n = 400) were 59.8 yrs and 25.1 kg/m2, respectively, and 98% of subjects were white. From baseline to month 3, mean AST: ALT ratio change was +1.0% in the COMT (rs4680) A/G genotype versus -4.8% in the A/A genotype (p = 0.03). From baseline to months 6 and 9, respectively, mean ALT change was +78.1% and +82.1% in the UGT1A4 (rs6755571) A/C genotype versus +28.0% and +30.1% in the C/C genotype (p < 0.001 and p = 0.004, respectively). The UGT1A4 (rs6755571) A/C genotype may be an important risk factor for clinically-relevant serum transaminase elevations with 6-9 months of high-dose GTE supplementation among postmenopausal women. Understanding the genetic underpinnings of GTE-related hepatotoxicity may allow for a genetically-informed paradigm for therapeutic use of GTE.


Assuntos
Catequina , Doença Hepática Induzida por Substâncias e Drogas , Extratos Vegetais , Feminino , Humanos , Antioxidantes , Catecol O-Metiltransferase/genética , Doença Hepática Induzida por Substâncias e Drogas/genética , Suplementos Nutricionais , Genótipo , Glucuronosiltransferase/genética , Extratos Vegetais/toxicidade , Chá/toxicidade
10.
J Nutr Sci ; 12: e100, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37771506

RESUMO

Research suggests that adiponectin, leptin, and genetic polymorphisms such as catechol-O-methyltransferase (COMT) genotype may play an integral role in blood pressure status and thereby cardiovascular health. This is an area especially important for women who are post-menopause; however, the current literature investigating these associations is limited. This study was a cross-sectional secondary analysis of baseline data (N 237) from the Minnesota Green Tea Trial (MGTT). The current study explored the relationships between plasma adiponectin, leptin, and COMT genotype on blood pressure measures. Plasma adiponectin and leptin were obtained after an overnight fast of at least 10 h and were measured by the radioimmunoassay method. The relationships were analysed using multiple linear regression after adjusting for potential confounders. Effect modifications by age, body mass index (BMI) category, blood pressure category, antihypertensive medication use, and COMT genotype were also investigated. The majority of participants were non-Hispanic (97⋅9 %) and Caucasian (94⋅9 %). Mean (sd) age and BMI were 60⋅7 (5⋅0) years and 28⋅2 (2⋅9) kg/m2, respectively. After adjustment for confounding variables, neither plasma adiponectin, plasma leptin nor COMT genotype was associated with systolic or diastolic blood pressure measures. The results of stratified analyses also did not reveal any significant interactions or associations. Based on the findings of this study, which utilised more rigorous statistical methods than previous research, neither adiponectin, leptin nor COMT genotype play a role in blood pressure measures in women who are post-menopause.

11.
Nutr Res ; 113: 29-38, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37011435

RESUMO

Green tea extract (GTE) is a potential mitigator of oxidative stress, and F2-isoprostanes are a reliable biomarker of oxidative stress. Genetic polymorphisms in the catechol-o-methyltransferase (COMT) gene may modify tea catechin metabolism, prolonging exposure. We hypothesized that GTE supplementation would decrease plasma F2-isoprostanes concentrations compared with placebo and that participants with the COMT genotype polymorphisms would experience a more significant expression of this outcome. This study was a secondary analysis of the Minnesota Green Tea Trial, a randomized placebo-controlled, double-blinded trial investigating the effects of GTE in women who were generally healthy and postmenopausal. The treatment group consumed 843 mg of epigallocatechin gallate daily for 12 months versus placebo. Participants in this study had a mean age of 60 years, were predominantly White, and most had a healthy body mass index. GTE supplementation did not significantly change plasma F2-isoprostanes concentrations compared with placebo after 12 months (P for overall treatment = .07). There were no significant interactions between treatment and age, or body mass index, physical activity, smoking history, and alcohol intake. COMT genotype did not modify the effect of GTE supplementation on F2-isoprostanes concentrations in the treatment group (P = .85). Among participants in the Minnesota Green Tea Trial, consuming GTE supplements daily for 1 year did not result in a significant decrease in plasma F2-isoprostanes concentrations. Likewise, the COMT genotype did not modify the effect of GTE supplementation on F2-isoprostanes concentrations.


Assuntos
Catequina , F2-Isoprostanos , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Catecol O-Metiltransferase/genética , Isoprostanos , Antioxidantes , Chá , Suplementos Nutricionais , Extratos Vegetais/uso terapêutico , Catequina/farmacologia
12.
Nutr Cancer ; 63(6): 930-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21745038

RESUMO

Substantial evidence relates increased sex hormone concentrations with increased breast cancer risk. Varying omega-3 (n-3) fatty acid (FA) intake may lead to alterations in eicosanoid balance and changes in circulating sex hormones that reduce risk. To clarify effects of dietary fat and n-3 FA intake on breast cancer risk markers, circulating sex hormones and urinary eicosanoids were measured in response to controlled feeding of diets designed to increase plasma concentrations of n-3 FA. A controlled cross-over feeding trial in postmenopausal women was conducted using 3 diets: high fat (HF; 40% energy from fat), low fat (LF; 20% energy from fat), and low fat plus n-3 FA (LFn3; 20% of energy from fat plus 3% of energy from n-3 FA) in 8-wk feeding periods. Plasma phospholipid fatty acid n-3 increased with the LFn3 relative to HF and LF (P < 0.0001). Plasma estradiol increased by 51% with HF (P = 0.03). Urinary prostaglandin E metabolite increased with HF relative to LF (P = 0.02) and urinary 11-dehydro-thromboxane B(2) increased with HF (P = 0.01). These results do not support a role of n-3 FA in the reduction of sex hormone levels.


Assuntos
Gorduras na Dieta/administração & dosagem , Eicosanoides/urina , Ácidos Graxos Ômega-3/administração & dosagem , Hormônios Esteroides Gonadais/sangue , Pós-Menopausa , Idoso , Peso Corporal , Neoplasias da Mama , Estudos Cross-Over , Dieta , Ingestão de Energia , Feminino , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Fosfolipídeos/sangue , Fatores de Risco , Inquéritos e Questionários
13.
Nutr Cancer ; 63(5): 743-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21711174

RESUMO

Insulin-like growth factor 1 (IGF-1) is an anabolic hormone important for growth and development. However, high-circulating serum concentrations in adults are associated with increased risk of postmenopausal breast cancer. Nutritional status and specific foods influence serum IGF-1 concentrations. Breast cancer incidence is typically low in Asian countries where soy is commonly consumed. Paradoxically, soy supplement trials in American women have reported significant increases in IGF-1. Seaweed also is consumed regularly in Asian countries where breast cancer risk is low. We investigated the possibility that seaweed could modify soy-associated increases in IGF-1 in American women. Thirty healthy postmenopausal women (mean age 58 yr) participated in this 14-wk double-blinded, randomized, placebo-controlled crossover clinical trial. Participants consumed 5 g/day placebo or seaweed (Alaria esculenta) in capsules for 7 wk. During the 7th wk, a high-soy protein isolate powder was added (2 mg/kg body weight aglycone equivalent isoflavones). Overnight fasting blood samples were collected after each intervention period. Soy significantly increased serum IGF-1 concentrations compared to the placebo (21.2 nmol/L for soy vs. 16.9 nmol/L for placebo; P = 0.0001). The combination of seaweed and soy significantly reduced this increase by about 40% (21.2 nmol/L for soy alone vs. 19.4 nmol/L; P = 0.01). Concurrent seaweed and soy consumption may be important in modifying the effect of soy on IGF-1 serum concentrations.


Assuntos
Suplementos Nutricionais , Glycine max/química , Fator de Crescimento Insulin-Like I/análise , Phaeophyceae/química , Pós-Menopausa/sangue , Alga Marinha/química , Idoso , Biomarcadores/sangue , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/prevenção & controle , Cápsulas , Estudos Cross-Over , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Risco , Sementes/química
14.
Nutr Cancer ; 63(3): 376-80, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21462084

RESUMO

Higher levels of insulin and insulin-like growth factor 1 (IGF-1) increase cancer risk by stimulating cell proliferation and increasing survival of DNA-damaged cells through antiapoptotic mechanisms. Laboratory studies suggest that flaxseed added to the diet may lower circulating levels of insulin and IGF-1, but there is limited information on the effects of dietary flaxseed on these biomarkers of cancer risk in humans. The aim of this study was to determine the effect of flaxseed supplementation in postmenopausal women on serum levels of insulin-like growth factor 1 (IGF-1), insulin-like growth factor binding protein 3 (IGF-BP3), and C-peptide, a marker of insulin production. Forty-eight postmenopausal women participated in this 12-wk baseline to postintervention study. Participants were asked to consume 7.5 g per day of ground flaxseed for 6 wk and 15 g per day for an additional 6 wk. No significant changes were observed in blood levels of IGF-1, IGF-BP3, or C-peptide over the study intervention. Flaxseed supplementation did not impact circulating levels of IGF-1, IGF-BP3, or C-peptide. Longer duration of intake may be necessary to observe changes in these biomarkers of cancer risk.


Assuntos
Peptídeo C/sangue , Dieta , Linho , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Análise de Variância , Biomarcadores/sangue , Índice de Massa Corporal , Peptídeo C/metabolismo , Feminino , Seguimentos , Humanos , Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Pós-Menopausa/metabolismo , Fatores de Risco , Inquéritos e Questionários
15.
Qual Health Res ; 21(9): 1191-204, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21508251

RESUMO

In this article, we explore an area little researched within the literature on body dissatisfaction: the content and functions of body talk. We interviewed 60 diverse, college-educated women aged 18 to 30 in the urban United States about how social contacts talked about their bodies. Half the women, and by their reports, half their contacts (N = 295) endorsed some ideal body, most often the thin model. The other half favored a "healthy," "average" range in body size, shape, and/or appearance. Excepting family members, contacts gave mostly positive comments about women's bodies or appearance, or made no comments. Many critiqued their own bodies, however, as did nearly half the women participants. We suggest that these women exempted others, but not themselves, from critical body surveillance, rendering contestation of the ideal theoretical. We also suggest that the parallel airing of self-criticism repeatedly circulated through speech, if not through practice, the imperative to regulate one's own gendered body toward unattainable normativity.


Assuntos
Transtornos Dismórficos Corporais/psicologia , Imagem Corporal , Cultura , Relações Interpessoais , Satisfação Pessoal , Autoimagem , Adaptação Psicológica , Adolescente , Adulto , Índice de Massa Corporal , Feminino , Humanos , Entrevista Psicológica , Grupo Associado , Psicometria , Pesquisa Qualitativa , Fatores Sexuais , Inquéritos e Questionários , Adulto Jovem
16.
Nutrients ; 13(6)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204023

RESUMO

The purpose of this cross-sectional study was to examine the relationship between diet and anthropometric measures in postmenopausal women. Data collected from 937 women enrolled in the Minnesota Green Tea Trial (NTC00917735) were used for this analysis. Dietary intake and health-related data were collected via questionnaires. Body weight, height, and waist circumference (WC) were measured by the study staff. The mean age of participants was 59.8 years and mean WC was 83 cm. Approximately 30% of the participants had WC greater than 88 cm. Healthy Eating Index-2015 score was 72.6 and the Dietary Inflammatory Index score was 0. Intakes of whole grains, dairy, protein, sodium, and saturated fat did not meet the dietary guidelines. Only 12.5% consumed the recommended daily amount of calcium (mean intake = 765 mg/day). When calcium supplements were considered, only 35.2% of the participants had adequate intakes, even though 68.9% reported taking a calcium supplement. We found that age and number of medications taken were significantly associated with waist circumference (p = 0.005). Women who reported taking two or more medications had greater WC (85 cm) compared to women who reported not taking any medications (82.2 cm), p = 0.002. Our findings suggest that achieving adequate calcium and vitamin D intake may be challenging to postmenopausal women.


Assuntos
Antropometria , Dieta Saudável/estatística & dados numéricos , Fidelidade a Diretrizes/estatística & dados numéricos , Pós-Menopausa , População Branca/estatística & dados numéricos , Idoso , Cálcio da Dieta/análise , Estudos Transversais , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Política Nutricional , Ensaios Clínicos Controlados Aleatórios como Assunto , Vitamina D/análise , Circunferência da Cintura
17.
J Menopausal Med ; 27(2): 79-86, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34463071

RESUMO

OBJECTIVES: The purpose of this cross-sectional study was to examine whether single nucleotide polymorphisms (SNPs) in enzymes that metabolize sex steroid hormones were associated with the blood levels of these hormones in postmenopausal women and if the use of menopausal hormone therapy (MHT) could modify this association. METHODS: Baseline data were collected from 932 postmenopausal women enrolled in the Minnesota Green Tea Trial. Participants filled out a questionnaire about their demographics, lifestyle factors, and medical and reproductive history. Free, bioavailable, and total serum levels of reproductive hormones were measured through liquid chromatography/tandem mass spectrometry. For genotyping of UGT1A1 (rs10928303), UGT1A4 (rs10929301, rs11673726), UGT1A6 (rs1105879, rs2070959, rs6759892), UGT1A8 (rs10167119), UGT2B7 (rs7439366), and SULT1A1 (rs9282861, rs1968752), mass spectrometry based on multiplex methods and TaqMan assays were performed. Adjusted linear models were fit to assess the associations between SNPs and blood hormones using age, body mass index (BMI), and MHT as covariates. RESULTS: The mean age was 59.8 years, and the mean BMI was 25.1 kg/m². Past or recent use of MHT was reported by 41.2% of the participants. SNPs in SULT1A1 (rs1968752 and rs9282861) and UGT1A4 (rs11673726) genes were significantly associated with estrone levels, whereas SNPs in UGT1A6 (rs6759892) and UGT1A8 (rs10167119) genes were significantly associated with bioavailable estradiol levels. CONCLUSIONS: There was no evidence that MHT use modified the association between SNPs and sex-steroid hormone levels; however, further studies are needed to establish the potential clinical significance of UGT1A4 (rs11673726), UGT1A6 (rs6759892), and UGT1A8 (rs10167119) SNPs and the modulation of hormone levels in postmenopausal women.

18.
Curr Dev Nutr ; 5(Suppl 4): 5-12, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34222763

RESUMO

This compilation includes the stories of 5 Native American and First Nation elders, in which they share their wisdom, experience, and opinions on Indigenous food systems and health. Each of these elders participated in the Fourth Annual Conference on Native American Nutrition, held in September 2019 at Mystic Lake Center on land of the Shakopee Mdewakanton Sioux Community in Prior Lake, Minnesota.

19.
Reprod Toxicol ; 100: 60-67, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33383165

RESUMO

Concerns that the phytoestrogens (isoflavones) in soy may feminize men continue to be raised. Several studies and case-reports describing feminizing effects including lowering testosterone levels and raising estrogen levels in men have been published. For this reason, the clinical data were meta-analyzed to determine whether soy or isoflavone intake affects total testosterone (TT), free testosterone (FT), estradiol (E2), estrone (E1), and sex hormone binding globulin (SHBG). PubMed and CAB Abstracts databases were searched between 2010 and April 2020, with use of controlled vocabulary specific to the databases. Peer-reviewed studies published in English were selected if (1) adult men consumed soyfoods, soy protein, or isoflavone extracts (from soy or red clover) and [2] circulating TT, FT, SHBG, E2 or E1 was assessed. Data were extracted by two independent reviewers. With one exception, studies included in a 2010 meta-analysis were included in the current analysis. A total of 41 studies were included in the analyses. TT and FT levels were measured in 1753 and 752 men, respectively; E2 and E1 levels were measured in 1000 and 239 men, respectively and SHBG was measured in 967 men. Regardless of the statistical model, no significant effects of soy protein or isoflavone intake on any of the outcomes measured were found. Sub-analysis of the data according to isoflavone dose and study duration also showed no effect. This updated and expanded meta-analysis indicates that regardless of dose and study duration, neither soy protein nor isoflavone exposure affects TT, FT, E2 or E1 levels in men.


Assuntos
Estrogênios/sangue , Isoflavonas/administração & dosagem , Fitoestrógenos/administração & dosagem , Proteínas de Soja/administração & dosagem , Testosterona/sangue , Adolescente , Adulto , Idoso , Dieta , Suplementos Nutricionais , Feminização/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Nutr Cancer ; 62(2): 175-80, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20099191

RESUMO

Flaxseed is a rich source of dietary lignans. It has been hypothesized that lignans may decrease breast cancer risk through modulation of endogenous hormone levels. The aim of this study was to determine the effect of flaxseed supplementation on urinary levels of estrogen metabolites that may be involved in the development of breast cancer. Forty-three postmenopausal women participated in this 12-wk preintervention-postintervention study. Participants consumed 7.5 g/day of ground flaxseed for 6 wk, followed by 15 g/day for an additional 6 wk. The mean urinary level of 16alpha -hydroxyestrone (16alpha -OHE1) was higher at the end of 12 wk compared to baseline (change of 1.32 ug/day, P = 0.02). There was no significant change in 2-OHE1 excretion. The mean urinary level of the 2-OHE1/16alpha -OHE1 ratio was lower at the end of 12 wk compared to baseline (change of -1.1, P = 0.02). Mean urinary excretion of 2-methoxyestradiol was also lower at 12 wk than at baseline (P = 0.03). Based on the current paradigm of the effects of estrogen metabolism on breast cancer risk, the regimen of dietary flaxseed intake used in this study did not appear to favorably alter breast cancer risk through shifts in estrogen metabolism pathways in postmenopausal women.


Assuntos
Dieta , Estrogênios/urina , Linho , Pós-Menopausa/urina , 2-Metoxiestradiol , Índice de Massa Corporal , Ingestão de Energia , Estradiol/análogos & derivados , Estradiol/urina , Feminino , Humanos , Hidroxiestronas/urina , Pessoa de Meia-Idade
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