NCT03689608

Daily vs Intermittent Restriction of Energy: Controlled Trial to Reduce Diabetes Risk (DIRECT)

Completed NA Last updated 11 January 2022

What this trial tests

NA trial testing Intermittent Fasting (IF) in Individuals at Risk of Developing Diabetes in 209 participants. Completed in 30 November 2021.

Timeline

26 September 2018

Primary endpoint
30 November 2020

30 November 2021

Quick facts

Lead sponsor	University of Adelaide
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	none
Primary purpose	basic science
Enrollment	209
Start date	26 September 2018
Primary completion	30 November 2020
Estimated completion	30 November 2021
Sites	1 location across Australia

Drugs / interventions tested

• Intermittent Fasting (IF)
• Daily Restriction (DR)
• standard care (SC)

Conditions studied

• Individuals at Risk of Developing Diabetes — all drugs for Individuals at Risk of Developing Diabetes →

Sponsor

University of Adelaide

Who can join

Adults 35 to 75, any sex, with Individuals at Risk of Developing Diabetes. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

In this randomized controlled trial, the investigators will compare the long term effectiveness of intermittent fasting (IF) versus an energy matched moderate calorie restriction (CR) over 18 months, and relative to a non-active intervention standard control (SC) in individuals who are at increased risk of developing type 2 diabetes. All participants will be required to attend the blood tests following a 12-hour overnight fast for the "A" visit at Month 0, 2, 6 (active) and 18 (follow up).

Fast424hGlucose: A subset of 100 participants enrolled in either IF or CR group in the parent study will be fitted with a continuous glucose monitor (CGM) to measure 24-hour glycaemic profile at month 0 and month 6.

Fast4Switch: Additional bloods will be collected after a "B" visit at month 6 to compare the fed to fasted switch. The B samples will be collected after a 12-hour overnight fast (CR, SC) or 20-hour fast (IF) to assess the metabolic switch to fasting in metabolites and hormones.

Fast4Stress: Additional subcutaneous adipose tissue, urine and saliva samples will be collected in \~32 men in IF and CR groups at month 0 and 6 at A and B visits to examine changes in stress response and resistance markers.

Experience2Fast: In-depth, semi-structured interviews will be carried out at month-8 follow-up visit in a subset of completers from IF or CR groups to explore the experience of intervention diets and understand contributing factors towards change and maintenance of dietary behaviours.

Fast4Flux: Additional blood samples will be collected in \~100 individuals in SC, IF and CR groups at month 0, month 2 and month 6 at A visit to measure autophagic flux in peripheral blood mononuclear cells following treatment of whole blood.

Publications & conference data

5 peer-reviewed publications reference this trial (live from Europe PMC):

1. Intermittent fasting plus early time-restricted eating versus calorie restriction and standard care in adults at risk of type 2 diabetes: a randomized controlled trial.
   Teong XT, Liu K, Vincent AD, Bensalem J, et al · · 2023 · cited 87× · PMID 37024596 · DOI 10.1038/s41591-023-02287-7
2. Intermittent fasting for the prevention of cardiovascular disease.
   Allaf M, Elghazaly H, Mohamed OG, Fareen MFK, et al · · 2021 · cited 66× · PMID 33512717 · DOI 10.1002/14651858.cd013496.pub2
3. The Effect of Intermittent Fasting on Appetite: A Systematic Review and Meta-Analysis.
   Elsworth RL, Monge A, Perry R, Hinton EC, et al · · 2023 · cited 17× · PMID 37299567 · DOI 10.3390/nu15112604
4. Basal autophagic flux measured in blood correlates positively with age in adults at increased risk of type 2 diabetes.
   Bensalem J, Teong XT, Hattersley KJ, Hein LK, et al · · 2023 · cited 16× · PMID 37498479 · DOI 10.1007/s11357-023-00884-5
5. Exploring the impact of intermittent fasting plus time-restricted eating versus calorie restriction on eating behavior, mood, sleep, quality of life in adults with obesity.
   Teong XT, Liu K, Vincent AD, Liu B, et al · · 2026 · PMID 42208206 · DOI 10.1016/j.clnu.2026.106686