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Comparison of Weight Loss Induced by Intermittent Fasting Versus Daily Caloric Restriction in Individuals with Obesity: A 1-Year Randomized Trial

Award Number: R01DK111622
ORGANIZATION: NATIONAL INSTITUTE OF DIABETES & DIGESTIVE & KIDNEY DISEASES
OPDIV: NIH
AWARD CLASS: DISCRETIONARY
AWARD ACTIVITY TYPE: SCIENTIFIC/HEALTH RESEARCH (INCLUDES SURVEYS)
PERIOD OF PERFORMANCE START DATE: 09/15/2017
PERIOD OF PERFORMANCE END DATE: 06/30/2024

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Comparison of Weight Loss Induced by Intermittent Fasting Versus Daily Caloric Restriction in Individuals with Obesity: A 1-Year Randomized Trial - Project Summary/Abstract Restricting daily calorie intake is the primary dietary strategy currently used to treat obesity. However, this approach is not effective for all individuals. Further, adherence to daily caloric restriction (DCR) typically decreases over time and many individuals who lose weight with this strategy will regain. Thus, novel dietary interventions are needed to provide a broader range of treatment options. The objective of this proposal is to determine if intermittent fasting (IMF) is an effective dietary strategy for treatment of obesity. IMF is an alternative method of reducing energy intake (EI) which has gained lay popularity in recent years as a strategy for weight loss. Short-term studies suggest IMF produces 3-8% weight loss in individuals with overweight and obesity. However, few studies have compared IMF to DCR and no studies have evaluated whether IMF is an effective long-term (≥1 year) weight loss strategy. Data from an 8-week pilot study comparing IMF to DCR suggests IMF is safe, tolerable, and produces similar short-term weight loss. After 6 months of unsupervised follow-up, changes in body composition tended to be more favorable with IMF and almost twice as many IMF participants maintained a ≥5 kg weight loss. Thus, IMF may be a more effective dietary strategy for sustaining weight loss than DCR. However, longer-term data are needed and little is known about adherence to IMF or the impact of IMF on energy expenditure (EE). Short-term studies suggest adherence to IMF may be superior to DCR, however, energy intake (EI) was based on self-report which may have significant limitations. Pilot data suggests resting energy expenditure (REE) was preserved during IMF-induced weight loss, which could decrease risk for weight regain. However, the impact of IMF on other components of EE including physical activity (PA) is largely unexamined. The study design is a pragmatic 1-year randomized trial to compare weight loss generated by IMF vs DCR. The targeted weekly energy deficit will be equivalent: DCR will be prescribed a 30% daily energy restriction and IMF will be prescribed a modified fast (75% energy restriction) on 3 non-consecutive days per week. The hypothesis is that a weight loss program based on IMF as the primary dietary strategy will result in greater weight loss at 1 year compared to a program based on traditional DCR. Aim 1 will compare weight loss and changes in body composition and metabolic parameters induced by IMF and DCR at 1 year. Aim 2 will evaluate the impact of IMF (compared to DCR) on EI and dietary adherence. Aim 3 will evaluate the impact of IMF (compared to DCR) on components of EE and patterns of PA. Aim 4 will explore predictors of weight loss within both IMF and DCR. The approach is innovative as the targeted energy deficit will be matched between groups and EI will be assessed objectively (using doubly-labeled water) to provide an accurate comparison of adherence. In addition, both intervention groups will receive guidelines-based behavioral support to compare IMF to the current standard of care (DCR) in a more robust fashion. This study is significant as it could identify an effective alternative dietary strategy to help more people achieve and sustain weight loss. !


Issue Date FY	Funding FY	Legal Entity Name	Legal Entity Address	Legal Entity City	Legal Entity State	Legal Entity Zip Code	Legal Entity COUNTY	Legal Entity COUNTRY	Assistance Listing	Award Code	Budget Year	Action Date	Action Type	Action Amount

Issue Date FY: 2025 ( Subtotal = -$4,368 )
2025	2021	THE REGENTS OF THE UNIV. OF COLORADO	13001 E 17TH PL STE F428	AURORA	CO	80045	ADAMS	USA	Diabetes, Digestive, and Kidney Diseases Extramural Research	000	5	1/3/2025	NON-COMPETING CONTINUATION	-$4,368
														Subtotal = -$4,368

Issue Date FY: 2023 ( Subtotal = $0 )
2023	2021	REGENTS OF THE UNIVERSITY OF COLORADO, THE	13001 E 17TH PLACE F428	AURORA	CO	80045	ADAMS	USA	Diabetes, Digestive, and Kidney Diseases Extramural Research	000	5	4/7/2023	NON-COMPETING CONTINUATION	$0
														Subtotal = $0

Issue Date FY: 2021 ( Subtotal = $643,662 )
2021	2021	REGENTS OF THE UNIVERSITY OF COLORADO, THE	13001 E 17TH PLACE F428	AURORA	CO	80045	ADAMS	USA	Diabetes, Digestive, and Kidney Diseases Extramural Research	000	5	6/28/2021	NON-COMPETING CONTINUATION	$643,662
														Subtotal = $643,662

Issue Date FY: 2020 ( Subtotal = $658,037 )
2020	2020	REGENTS OF THE UNIVERSITY OF COLORADO, THE	13001 E 17TH PLACE F428	AURORA	CO	80045	ADAMS	USA	Diabetes, Digestive, and Kidney Diseases Extramural Research	000	4	6/9/2020	NON-COMPETING CONTINUATION	$658,037
														Subtotal = $658,037

Issue Date FY: 2019 ( Subtotal = $1,152,860 )
2019	2019	REGENTS OF THE UNIVERSITY OF COLORADO, THE	13001 E 17TH PLACE F428	AURORA	CO	80045	ADAMS	USA	Diabetes, Digestive, and Kidney Diseases Extramural Research	000	3	7/22/2019	NON-COMPETING CONTINUATION	$1,152,860
														Subtotal = $1,152,860

Issue Date FY: 2018 ( Subtotal = $1,190,633 )
2018	2018	REGENTS OF THE UNIVERSITY OF COLORADO, THE	13001 E 17TH PLACE F428	AURORA	CO	80045	ADAMS	USA	Diabetes, Digestive, and Kidney Diseases Extramural Research	000	2	7/17/2018	NON-COMPETING CONTINUATION	$683,663
2018	2018	REGENTS OF THE UNIVERSITY OF COLORADO, THE	13001 E 17TH PLACE F428	AURORA	CO	80045	ADAMS	USA	Trans-NIH Research Support	001	2	8/3/2018	SUPPLEMENT FOR EXPANSION	$506,970
														Subtotal = $1,190,633

Issue Date FY: 2017 ( Subtotal = $709,678 )
2017	2017	REGENTS OF THE UNIVERSITY OF COLORADO, THE	13001 E 17TH PLACE F428	AURORA	CO	80045	ADAMS	USA	Diabetes, Digestive, and Kidney Diseases Extramural Research	000	1	9/2/2017	NEW	$709,678
														Subtotal = $709,678

Grand Total All Awards = $4,350,502

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Comparison of Weight Loss Induced by Intermittent Fasting Versus Daily Caloric Restriction in Individuals with Obesity: A 1-Year Randomized Trial

Award Number: R01DK111622

ORGANIZATION: NATIONAL INSTITUTE OF DIABETES & DIGESTIVE & KIDNEY DISEASES

OPDIV: NIH

AWARD CLASS: DISCRETIONARY

AWARD ACTIVITY TYPE: SCIENTIFIC/HEALTH RESEARCH (INCLUDES SURVEYS)

PERIOD OF PERFORMANCE START DATE: 09/15/2017

PERIOD OF PERFORMANCE END DATE: 06/30/2024

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