Denne side blev automatisk oversat, og nøjagtigheden af ​​oversættelsen er ikke garanteret. Der henvises til engelsk version for en kildetekst.

Glycemic Index and Brain Function

1. februar 2012 opdateret af: David Alsop, Beth Israel Deaconess Medical Center

The Effects of Dietary Glycemic Index on Brain Function

The investigators propose examine the effects of the dietary factor glycemic index (GI) on brain areas that control food intake and hunger. This knowledge could help design dietary approaches that decrease hunger, and thus promote new weight loss strategies.

Studieoversigt

Status

Afsluttet

Betingelser

Intervention / Behandling

Detaljeret beskrivelse

Most individuals have great difficulty following reduced calorie diets because they experience increased hunger. This process is regulated by specific brain areas. Though many psychological and environmental factors are involved, physiological effects of diet may have a significant impact. The postprandial rise in blood glucose, quantified by the glycemic index (GI), is of particular interest. High GI meals elicit hormonal events that limit availability of metabolic fuels, causing hunger and overeating, especially in people with high insulin secretion.

Our aim is to examine how postprandial changes after high versus low GI meals affect hunger and brain function in areas of intake control. Specifically, we speculate that obese individuals will demonstrate functional changes in brain areas of intake control and increased hunger after a high versus low GI meal.

We will recruit obese, young adults and quantify their insulin secretion during a 2-hour oral glucose tolerance test. A brief practice MRI session will serve to familiarize the subjects with the scanning process. During the two test sessions, standardized test meals with high versus low GI will be given in a randomized, blinded cross-over design. Serial blood levels of hormones, metabolic fuels, and metabolites will be correlated with perceived hunger, and a perfusion MRI scan will be performed to assess brain activation during the late postprandial phase, at the nadir of blood sugar and insulin levels (4 hours postprandial).

This work will inform an integrated physiological model relating peripheral postprandial changes to brain function and hunger. In addition, findings may provide evidence of a novel diet-phenotype, in which baseline clinical characteristics can be used to predict which weight loss diet will work best for a specific individual. Metabolite profiling might shed light on the mechanisms linking diet composition to brain function, and provide feasible clinical markers of the identified phenotype to facilitate translation into practice.

Undersøgelsestype

Interventionel

Tilmelding (Faktiske)

12

Fase

  • Ikke anvendelig

Kontakter og lokationer

Dette afsnit indeholder kontaktoplysninger for dem, der udfører undersøgelsen, og oplysninger om, hvor denne undersøgelse udføres.

Studiesteder

  • Forenede Stater
    • Massachusetts
      • Boston, Massachusetts, Forenede Stater, 02215
        • Beth Israel Deaconess Medical Center
      • Boston, Massachusetts, Forenede Stater, 02115
        • Children's Hospital Boston
      • Boston, Massachusetts, Forenede Stater, 02215
        • Brigham and Women's Hospital

Deltagelseskriterier

Forskere leder efter personer, der passer til en bestemt beskrivelse, kaldet berettigelseskriterier. Nogle eksempler på disse kriterier er en persons generelle helbredstilstand eller tidligere behandlinger.

Berettigelseskriterier

Aldre berettiget til at studere

18 år til 35 år (Voksen)

Tager imod sunde frivillige

Ja

Køn, der er berettiget til at studere

Han

Beskrivelse

Inclusion criteria

  1. Males age 18 to 35 years
  2. BMI less than or equal to 25 for age and gender

Exclusion criteria

  1. weight > 300 lbs
  2. largest body circumference > 144cm
  3. body shape incompatible with MRI scanner or equipment
  4. MRI exclusion criteria
  5. large fluctuations in body weight (5% over preceding 6 months, 2.5% during the study)
  6. known medical problems that may affect metabolism or hormones
  7. diabetes mellitus (fasting plasma glucose ≥126 mg/dL)
  8. other abnormal laboratory screening tests
  9. taking any medications or dietary supplements that might affect body weight, appetite, or energy expenditure
  10. smoking or illicit substance abuse
  11. high levels of physical activity (>30 minutes per day, > 4days per week)
  12. currently following a weight loss diet
  13. allergies or intolerance to eggs, vanilla extract, equal, canola oil, milk, cornstarch, corn syrup

Studieplan

Dette afsnit indeholder detaljer om studieplanen, herunder hvordan undersøgelsen er designet, og hvad undersøgelsen måler.

Hvordan er undersøgelsen tilrettelagt?

Design detaljer

  • Primært formål: Behandling
  • Tildeling: Randomiseret
  • Interventionel model: Crossover opgave
  • Maskning: Firedobbelt

Våben og indgreb

Deltagergruppe / Arm
Intervention / Behandling
Aktiv komparator: Low GI
Andet: Low GI
Subjects will be instructed to consume a liquid test meal with a low GI over 5 minutes after baseline laboratory evaluations. The low and high GI meal contain similar amounts of milk, oil, dried egg whites, equal, and vanilla extract. The low GI meal corn-starch as a carbohydrate. Both meals have similar macronutrient composition (60% carbohydrate, 15% protein, 25% fat), micronutrient profiles, physical properties, palatability and sweetness. The high vs. low GI meals have a predicted difference in GI of 90 vs. 40, and consistent with this prediction, a pilot study in obese young adults found a 2.2-fold difference in glycemic response (p<0.001). The test meals will provide 25% of individual daily energy requirements.
Eksperimentel: High GI
Andet: High GI
Subjects will be instructed to consume a liquid test meal with a high GI over 5 minutes after baseline laboratory evaluations. The low and high GI meal contain similar amounts of milk, oil, dried egg whites, equal, and vanilla extract. The high GI meal contains corn-syrup as a carbohydrate. Both meals have similar macronutrient composition (60% carbohydrate, 15% protein, 25% fat), micronutrient profiles, physical properties, palatability and sweetness. The high vs. low GI meals have a predicted difference in GI of 90 vs. 40, and consistent with this prediction, a pilot study in obese young adults found a 2.2-fold difference in glycemic response (p<0.001). The test meals will provide 25% of individual daily energy requirements.

Hvad måler undersøgelsen?

Primære resultatmål

Resultatmål
Tidsramme
Blood Flow in Brain Areas of Intake Control.
Tidsramme: 4 hours postprandial
4 hours postprandial

Sekundære resultatmål

Resultatmål
Foranstaltningsbeskrivelse
Tidsramme
Subjective Hunger Rating
Tidsramme: Every 30 minutes for 5 hours.
Every 30 minutes for 5 hours.
Blood Glucose Level
Tidsramme: Every 30 minutes for 5 hours.
Every 30 minutes for 5 hours.
Blood Insulin Level
Tidsramme: Every 30 minutes for 5 hours
Every 30 minutes for 5 hours
Blood Glucagon Level
Tidsramme: Every 30 minutes for 5 hours.
Every 30 minutes for 5 hours.
Blood Growth Hormone Level
Tidsramme: Every 30 minutes for 5 hours.
Every 30 minutes for 5 hours.
Blood Epinephrine Level
Tidsramme: Every 30 minutes for 5 hours.
Every 30 minutes for 5 hours.
Blood Fatty Acids Level
Tidsramme: Every 30 minutes for 5 hours.
measuring metabolite profiles
Every 30 minutes for 5 hours.

Samarbejdspartnere og efterforskere

Det er her, du vil finde personer og organisationer, der er involveret i denne undersøgelse.

Sponsor

Beth Israel Deaconess Medical Center

Samarbejdspartnere

Boston Children's Hospital
Brigham and Women's Hospital

Efterforskere

  • Studieleder: Belinda S Lennerz, MD, PhD, Boston Children's Hospital
  • Ledende efterforsker: David Alsop, PhD, Beth Israel Deaconess Medical Center

Publikationer og nyttige links

Den person, der er ansvarlig for at indtaste oplysninger om undersøgelsen, leverer frivilligt disse publikationer. Disse kan handle om alt relateret til undersøgelsen.

Generelle publikationer

Datoer for undersøgelser

Disse datoer sporer fremskridtene for indsendelser af undersøgelsesrekord og resumeresultater til ClinicalTrials.gov. Studieregistreringer og rapporterede resultater gennemgås af National Library of Medicine (NLM) for at sikre, at de opfylder specifikke kvalitetskontrolstandarder, før de offentliggøres på den offentlige hjemmeside.

Studer store datoer

Studiestart

1. februar 2010

Primær færdiggørelse (Faktiske)

1. juni 2011

Studieafslutning (Faktiske)

1. september 2011

Datoer for studieregistrering

Først indsendt

5. februar 2010

Først indsendt, der opfyldte QC-kriterier

5. februar 2010

Først opslået (Skøn)

8. februar 2010

Opdateringer af undersøgelsesjournaler

Sidste opdatering sendt (Skøn)

2. februar 2012

Sidste opdatering indsendt, der opfyldte kvalitetskontrolkriterier

1. februar 2012

Sidst verificeret

1. februar 2012

Mere information

Begreber relateret til denne undersøgelse

Nøgleord

Andre undersøgelses-id-numre

  • RA-003

Disse oplysninger blev hentet direkte fra webstedet clinicaltrials.gov uden ændringer. Hvis du har nogen anmodninger om at ændre, fjerne eller opdatere dine undersøgelsesoplysninger, bedes du kontakte register@clinicaltrials.gov. Så snart en ændring er implementeret på clinicaltrials.gov, vil denne også blive opdateret automatisk på vores hjemmeside .

Kliniske forsøg med Low GI

Søg i lignende forsøg

Sponsorer og samarbejdspartnere

Medicinske tilstande

Narkotikainterventioner

CROs by country

CROs in Kuwait

Betingelser

Sjældne sygdomme

Narkotikainterventioner

Kosttilskud

Sponsor / samarbejdspartnere

Placeringer

3
Abonner