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Efeitos da ordem da dieta de dietas com baixo teor de gordura versus dietas com baixo teor de carboidratos na mudança de gordura corporal

Background:

In a previous study, participants were lived at the NIH and randomly received either a low-fat or a low-carbohydrate diet for 2 weeks and then switched to the other diet for 2 more weeks. Participants who received the low-carbohydrate diet first lost more body fat at the end of the study than those who received the low-fat diet first. Researchers want to see if they can repeat that result in a longer weight loss study when participants live at home.

Objective:

To test the effects of diet order in people receiving either a low-fat or low-carbohydrate diet first for 4 weeks and then immediately switched to the other diet for another 4 weeks.

Eligibility:

Adults aged 19 to 50 years with a body mass index of 25 or more.

Design:

Participants will complete the study at their homes, but there will be 3 required visits to the NIH. Participants will drink a special type of water 2 weeks before the baseline NIH visit and collect urine samples at home to measure how many calories they burn. Before the diets begin, participants will visit the NIH for baseline testing when they will have a metabolism test while relaxing in a bed with a plastic hood over their head to collect the air they breathe out. They will have scans to measure their bone density and how much muscle and body fat they have. They will give stool, blood, and urine samples.

Participants will be asked to eat a specific diet for 4 weeks followed by a different diet for 4 weeks. All meals will be delivered to the participants' homes. They will eat only the foods delivered.

Participants will weigh themselves daily. They will wear a monitor to track their physical activity and a sensor to measure their glucose levels. They will prick their finger each morning to test a drop of blood for ketones. Participants will meet virtually as a group with the study team weekly. Participants will have two more NIH visits towards the end of each diet period....

Visão geral do estudo

Status

Recrutamento

Descrição detalhada

Study Description:

This is an 8-week crossover outpatient feeding trial of a low carbohydrate versus a low-fat diet, each provided for 4 weeks in random order with no washout period, in adult volunteers with overweight or obesity.

Objectives:

Primary Objectives: To determine the effect of diet order on the mean total fat mass change in subjects randomized to receive either a low carbohydrate followed by a low fat diet or the reverse order, with each diet lasting for 4 weeks.

Secondary Objectives: To determine the effect of diet order on the mean rate of body weight change in subjects randomized to receive either a low carbohydrate followed by a low fat diet or the reverse order, with each diet lasting for 4 weeks and the rate of weight change is measured during the last 2 weeks of each diet. To determine the effect of diet order on mean total body weight change in subjects randomized to receive either a low carbohydrate followed by a low fat diet or the reverse order, with each diet lasting for 4 weeks.

Endpoints:

Primary Endpoint: Mean total fat mass change measured by dual energy X-ray absorptiometry at baseline and week 8.

Secondary Endpoints: Mean rate of weight change by linear mixed modeling of daily weight measurements. Mean total body weight change measured between baseline and week 8.

Tipo de estudo

Intervencional

Inscrição (Estimado)

42

Estágio

  • Não aplicável

Contactos e Locais

Esta seção fornece os detalhes de contato para aqueles que conduzem o estudo e informações sobre onde este estudo está sendo realizado.

Contato de estudo

  • Nome: Nan Zhai, C.R.N.P.
  • Número de telefone: (301) 827-3324
  • E-mail: nan.zhai@nih.gov

Estude backup de contato

Locais de estudo

    • Maryland
      • Bethesda, Maryland, Estados Unidos, 20892
        • Recrutamento
        • National Institutes of Health Clinical Center
        • Contato:

Critérios de participação

Os pesquisadores procuram pessoas que se encaixem em uma determinada descrição, chamada de critérios de elegibilidade. Alguns exemplos desses critérios são a condição geral de saúde de uma pessoa ou tratamentos anteriores.

Critérios de elegibilidade

Idades elegíveis para estudo

18 anos a 50 anos (Adulto)

Aceita Voluntários Saudáveis

Não

Gêneros Elegíveis para o Estudo

Tudo

Descrição

  • INCLUSION CRITERIA:

In order to be eligible to participate in this study, an individual must meet all of the following criteria:

  1. Stated willingness to comply with all study procedures and availability for the duration of the study
  2. Adults aged 18-50 years
  3. Weight stable (< +/- 5% over past 6 months) as determined by volunteer report
  4. Body mass index (BMI) >= 25 kg/m^2
  5. Agreement to adhere to Lifestyle Considerations throughout the study duration

EXCLUSION CRITERIA:

  1. Subjects with cardiac pacemakers or other implants that may be affected by or affect the DXA measurements
  2. Inadequate access to equipment required for the study (e.g., too little refrigerator storage space or a microwave oven that is too small) as determined by discretion of PI and/or study team
  3. Evidence of diseases or conditions that may influence appetite (e.g., cancer, diabetes, alterations of smell or taste post COVID-19), diseases or conditions that affect the immune system, or other conditions at the discretion of the PI and/or study team
  4. Taking prescription medications or other drugs that may influence metabolism (including but not limited to diet/weight-loss medication, some psychiatric medications, or other medications at the discretion of the PI and/or study team)
  5. People unlikely to adhere to a relatively consistent daily and weekly routine and avoid travel during their participation in the study. For example, people with occupations such as pilots, flight attendants, or frequently travel for work or pleasure.
  6. People unlikely to abstain from off study food or supplements that may impact metabolism or appetite at the discretion of the study team
  7. Positive pregnancy test or lactating as determined by volunteer report (women only)
  8. Inability or unwillingness to use birth control between screening and completion of the study (women only)
  9. Symptoms or signs of perimenopause or menopause by volunteer report (women only)
  10. Regular vigorous exercise >150 min per week as determined by volunteer report
  11. Alcohol consumption > 3 drinks per day as determined by volunteer report
  12. Regular use of tobacco (smoking, chewing, or vaping), nicotine replacement therapy, or illicit drugs over past 6 months as determined by volunteer report. Subjects may also be excluded based on a urine drug test.
  13. Psychological conditions as determined by DSM-5 Self-rated Level 1 Cross-cutting Symptom Measure such as (but not limited to) eating disorders, depression, bipolar disorders, that would be incompatible with safe and successful participation in this study, as determined by investigators
  14. Volunteers with strict dietary concerns (e.g. vegetarian or kosher diet, food allergies) or a reported dislike of a significant fraction of the study foods
  15. Volunteers unwilling or unable to give informed consent
  16. Non-English speakers due to unavailability of required questionnaires in other languages
  17. Resting Energy Expenditure test result within 10% of the 2500 calorie requirement at rest

Plano de estudo

Esta seção fornece detalhes do plano de estudo, incluindo como o estudo é projetado e o que o estudo está medindo.

Como o estudo é projetado?

Detalhes do projeto

  • Finalidade Principal: Ciência básica
  • Alocação: Randomizado
  • Modelo Intervencional: Atribuição cruzada
  • Mascaramento: Solteiro

Armas e Intervenções

Grupo de Participantes / Braço
Intervenção / Tratamento
Experimental: low-carbohydrate diet then low-fat diet

A low-carbohydrate followed by low-fat diet, each lasting for 4 weeks in adults with overweight or obesity

Consisting of 15 percent protein, 75 percent fat, and 10 percent carbohydrate

Consisting of 15 percent protein, 10 percent fat, and 75 percent carbohydrate

Experimental: low-fat diet then low-carbohydrate diet

A low-fat followed by low-carbohydrate diet, each lasting for 4 weeks in adults with overweight or obesity

Consisting of 15 percent protein, 75 percent fat, and 10 percent carbohydrate

Consisting of 15 percent protein, 10 percent fat, and 75 percent carbohydrate

O que o estudo está medindo?

Medidas de resultados primários

Medida de resultado
Descrição da medida
Prazo
Change in total fat mass
Prazo: 8 weeks

Change in total fat mass (kg) as measured by dual energy X-ray absorptiometry (DXA) from baseline to week 8

8 weeks

Medidas de resultados secundários

Medida de resultado
Descrição da medida
Prazo
Rate of body weight change from baseline to week 8
Prazo: 8 weeks

Rate of body weight change (kg/d) from baseline to week 8

8 weeks
Rate of body weight change during low-carbohydrate diet
Prazo: Last 2 weeks of low-carbohydrate diet period

Rate of body weight change (kg/d) during the last two weeks of the low-carbohydrate diet

Last 2 weeks of low-carbohydrate diet period
Rate of body weight change during low-fat diet
Prazo: Last 2 weeks of low-fat diet period

Rate of body weight change (kg/d) during the last two weeks of the low-fat diet

Last 2 weeks of low-fat diet period

Colaboradores e Investigadores

É aqui que você encontrará pessoas e organizações envolvidas com este estudo.

Investigadores

  • Investigador principal: Valerie L Darcey, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Publicações e links úteis

A pessoa responsável por inserir informações sobre o estudo fornece voluntariamente essas publicações. Estes podem ser sobre qualquer coisa relacionada ao estudo.

Datas de registro do estudo

Essas datas acompanham o progresso do registro do estudo e os envios de resumo dos resultados para ClinicalTrials.gov. Os registros do estudo e os resultados relatados são revisados ​​pela National Library of Medicine (NLM) para garantir que atendam aos padrões específicos de controle de qualidade antes de serem publicados no site público.

Datas Principais do Estudo

Início do estudo (Real)

28 de agosto de 2024

Conclusão Primária (Estimado)

30 de novembro de 2029

Conclusão do estudo (Estimado)

30 de novembro de 2029

Datas de inscrição no estudo

Enviado pela primeira vez

21 de março de 2024

Enviado pela primeira vez que atendeu aos critérios de CQ

21 de março de 2024

Primeira postagem (Real)

22 de março de 2024

Atualizações de registro de estudo

Última Atualização Postada (Real)

2 de novembro de 2026

Última atualização enviada que atendeu aos critérios de controle de qualidade

30 de outubro de 2026

Última verificação

29 de outubro de 2026

Mais Informações

Termos relacionados a este estudo

Plano para dados de participantes individuais (IPD)

Planeja compartilhar dados de participantes individuais (IPD)?

SIM

Descrição do plano IPD

Body fat and body weight data

Prazo de Compartilhamento de IPD

Upon publication in peer reviewed journal

Critérios de acesso de compartilhamento IPD

Open, general access

Tipo de informação de suporte de compartilhamento de IPD

  • PROTOCOLO DE ESTUDO
  • ANALYTIC_CODE

Informações sobre medicamentos e dispositivos, documentos de estudo

Estuda um medicamento regulamentado pela FDA dos EUA

Não

Estuda um produto de dispositivo regulamentado pela FDA dos EUA

Não

Essas informações foram obtidas diretamente do site clinicaltrials.gov sem nenhuma alteração. Se você tiver alguma solicitação para alterar, remover ou atualizar os detalhes do seu estudo, entre em contato com register@clinicaltrials.gov. Assim que uma alteração for implementada em clinicaltrials.gov, ela também será atualizada automaticamente em nosso site .

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