The Healthy Diet and Lifestyle Study II

Description

Intermittent energy restriction (IER) may have important advantages over daily energy restriction (DER) in producing sustained weight loss and reducing cancer risk. IER is already being promoted with limited evidence, thus, additional evidence is urgently needed from rigorously conducted clinical trials. IER has been proposed to invoke a greater metabolic shift to fat metabolism than DER and preferentially reduce central obesity. The Investigators adapted the IER and the Mediterranean diet (MED) approach which have been recommended as a healthy weight-loss diet in the management of non-alcoholic fatty liver disease, for an ethnically diverse population. The effectiveness was compared to an active comparator (DASH diet) in reducing overall and visceral adiposity in a randomized trial among 60 middle-aged adults with visceral obesity. This 12-week pilot demonstrated the feasibility and safety of IER and the culturally-adapted MED \[NCT03639350\]. The six-month randomized trial will demonstrate the superiority of IER over DER in reducing fat and total fat mass, and in improving cancer-related biomarkers and gut microbiome functions. This longer trial, to confirm safety and superiority of IER over DER in reducing VAT and liver fat will expand our understanding of adherence to IER and its effect on the gut microbiome as a possible mediator of systemic inflammation. The Investigators will conduct a 24-week randomized trial of IER+MED vs. MED/DER among 260 middle-aged adults of East-Asian, Native Hawaiian and other Pacific Islanders or White ethnicity with high VAT. The primary research question is whether a diet plan combining IER and the MED dietary pattern will be superior to MED/DER in reducing abdominal MRI-measured visceral and liver fat and dual-energy X-ray absorptiometry (DXA) measured total adiposity. The Healthy Diet and Lifestyle Study II (HDLS2) will recruit 312 men and women from the general population with VAT at or above the population-median (men: ≥90 cm2; women ≥80 cm2) and randomize them to the IER+MED or MED/DER diet (156 per group). The IER+MED group will follow IER for two consecutive days (70% energy restriction) and total energy MED diet for the other five days of the week, reaching an overall 20% energy restriction. The MED/DER group will be prescribed a 20% daily energy restriction. With an expected attrition rate of \~16% (10% in Pilot), the investigators expect 130 participants per group to complete the study.

Conditions

Intra-Abdominal Fat

Study Overview

Study Details

Study overview

Intermittent energy restriction (IER) may have important advantages over daily energy restriction (DER) in producing sustained weight loss and reducing cancer risk. IER is already being promoted with limited evidence, thus, additional evidence is urgently needed from rigorously conducted clinical trials. IER has been proposed to invoke a greater metabolic shift to fat metabolism than DER and preferentially reduce central obesity. The Investigators adapted the IER and the Mediterranean diet (MED) approach which have been recommended as a healthy weight-loss diet in the management of non-alcoholic fatty liver disease, for an ethnically diverse population. The effectiveness was compared to an active comparator (DASH diet) in reducing overall and visceral adiposity in a randomized trial among 60 middle-aged adults with visceral obesity. This 12-week pilot demonstrated the feasibility and safety of IER and the culturally-adapted MED \[NCT03639350\]. The six-month randomized trial will demonstrate the superiority of IER over DER in reducing fat and total fat mass, and in improving cancer-related biomarkers and gut microbiome functions. This longer trial, to confirm safety and superiority of IER over DER in reducing VAT and liver fat will expand our understanding of adherence to IER and its effect on the gut microbiome as a possible mediator of systemic inflammation. The Investigators will conduct a 24-week randomized trial of IER+MED vs. MED/DER among 260 middle-aged adults of East-Asian, Native Hawaiian and other Pacific Islanders or White ethnicity with high VAT. The primary research question is whether a diet plan combining IER and the MED dietary pattern will be superior to MED/DER in reducing abdominal MRI-measured visceral and liver fat and dual-energy X-ray absorptiometry (DXA) measured total adiposity. The Healthy Diet and Lifestyle Study II (HDLS2) will recruit 312 men and women from the general population with VAT at or above the population-median (men: ≥90 cm2; women ≥80 cm2) and randomize them to the IER+MED or MED/DER diet (156 per group). The IER+MED group will follow IER for two consecutive days (70% energy restriction) and total energy MED diet for the other five days of the week, reaching an overall 20% energy restriction. The MED/DER group will be prescribed a 20% daily energy restriction. With an expected attrition rate of \~16% (10% in Pilot), the investigators expect 130 participants per group to complete the study.

Effects of Intermittent Energy Restriction on Intra-Abdominal Fat and the Gut Microbiome: A Randomized Trial

The Healthy Diet and Lifestyle Study II

Condition
Intra-Abdominal Fat
Intervention / Treatment

-

Contacts and Locations

Honolulu

University of Hawaii Cancer Center, Honolulu, Hawaii, United States, 96813

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

For general information about clinical research, read Learn About Studies.

Eligibility Criteria

  • * Age 35-69 years old
  • * BMI between 25-40 kg/m2
  • * Currently non-smoking
  • * No serious health issues
  • * Fully vaccinated for COVID-19
  • * Normal blood chemistry profile
  • * East Asian (Chinese, Japanese, Korean), Filipino, Native Hawaiian/other Pacific Islander or white/European ancestry
  • * Non-drinkers / low habitual drinkers, i.e., men ≤15 drinks per week, women ≤10 drinks per week
  • * Volunteers living on the island of Oahu
  • * For peri-menopausal women, the investigators will require that they had their last period at least 1 year before baseline)
  • * DXA VAT ≥90 cm2 for men and ≥80 cm2 for women
  • * Able to read, speak, and write in English
  • * Pregnancy
  • * Contraindication to MR imaging (e.g. pacemaker, claustrophobia, metal implants)
  • * Previous surgery to remove any part of the small intestine, colon or rectum (e.g.
  • * For women, taking any anti-estrogen medications (e.g tamoxifen, Nolvadex, Istubal, Valodex)
  • * For men, taking any anti-androgen medications (e.g., Eulexin (flutamide); Anandron or Nilandron (nilutamide); Casodex (bicalutamide); Proscar or Propecia (finasteride); Avodart (dutasteride); or bexlosteride, izonsteride, turosteride, episteride).
  • * Diagnosis of Type 1 diabetes or Type 2 diabetes and taking insulin for treatment
  • * Diagnosis of thyroid conditions under treatment with hormones or medications.
  • * Serious health issues such as dialysis, organ transplant, celiac disease, Crohn's disease, chronic liver disease, active case of hepatitis B or C, chronic kidney disease, or any condition that, in the opinion of the investigator, is a contraindication to participation.
  • * Previous problem with fasting blood collection
  • * Cannot exercise (walk) for up to 1hr/day
  • * Treatments in past 6 months: chemotherapy or radiation of abdomen/pelvis; corticosteroid hormones; prescription weight loss drugs; estrogen/androgen receptor blockers
  • * Substantial weight change (\>20lbs) in past 6 months
  • * Antibiotic use in past 3 months
  • * Colonoscopy, sigmoidoscopy, colon irrigation/bowel cleaning in the past 3 months
  • * MRI/CAT scan with contrast in the past 2 weeks

Ages Eligible for Study

35 Years to 69 Years

Sexes Eligible for Study

ALL

Accepts Healthy Volunteers

Yes

Collaborators and Investigators

University of Hawaii,

Loic Le Marchand, MD, PhD, PRINCIPAL_INVESTIGATOR, University of Hawaii Cancer Research Center

Study Record Dates

2026-09-30