Skip to main content
  • U.S. Department of Health & Human Services
National Institutes of Health (NIH) - Turning Discovery into Health
  • Virtual Tour
  • En Español

Site Menu

  • Home
  • Health Information
    • Health Care Providers & Facilities
    • Health Info Lines
    • HealthCare.gov
    • Science Education Resources
    • NIH Clinical Research Trials and You
    • Talking to Your Doctor

    More »

    Quick Links

    • MedlinePlus Health Info
    • NIH News in Health
    • Wellness Toolkits
  • Grants & Funding
    • Grants Home Page
    • Find Funding
    • Due Dates
    • How to Apply
    • About Grants
    • Policy & Compliance
    • Grants News/Blog
    • Contracts
    • Loan Repayment

    More »

    Quick Links

    • RePORT
    • eRA Commons
    • NIH Common Fund
  • News & Events
    • News Releases
    • Digital Media Kits
    • Media Resources
    • Media Contacts
    • Images and B-roll
    • Events
    • Social Media

    More »

    Quick Links

    • NIH News in Health
    • NIH Research Matters
    • NIH Record
  • Research & Training
    • Medical Research Initiatives
    • Science Highlights
    • Science Education
    • Research in NIH Labs & Clinics
    • Training Opportunities
    • Library Resources
    • Research Resources
    • Clinical Research Resources
    • Safety, Regulation and Guidance

    More »

    Quick Links

    • PubMed
    • Stem Cell Information
    • OppNet
    • NIDB
    • NIH Blueprint for Neuroscience Research
  • Institutes at NIH
    • List of Institutes and Centers
    • NIH Office of the Director
    • Directors of NIH Institutes and Centers
    • NIH Institute and Center Contact Information

    More »

    Quick Links

    • NCI
    • NEI
    • NHLBI
    • NHGRI
    • NIA
    • NIAAA
    • NIAID
    • NIAMS
    • NIBIB
    • NICHD
    • NIDCD
    • NIDCR
    • NIDDK
    • NIDA
    • NIEHS
    • NIGMS
    • NIMH
    • NIMHD
    • NINDS
    • NINR
    • NLM
    • CC
    • CIT
    • CSR
    • FIC
    • NCATS
    • NCCIH
  • About NIH
    • Who We Are
    • What We Do
    • Jobs at NIH
    • Visitor Information
    • Frequently Asked Questions
    • Contact Us

    More »

    Quick Links

    • The NIH Director
    • Take the Virtual Tour
    • NIH…Turning Discovery Into Health®
    • Impact of NIH Research
    • Science, Health, and Public Trust

You are here

Home » News & Events » News Releases

News Releases

News Release

Thursday, August 13, 2015

NIH study finds cutting dietary fat reduces body fat more than cutting carbs

Image of a scale A scale shows pasta/carbs weighed against butter/fat. Dr. Kevin Hall, NIDDK

In a recent study, restricting dietary fat led to body fat loss at a rate 68 percent higher than cutting the same number of carbohydrate calories when adults with obesity ate strictly controlled diets.  Carb restriction lowered production of the fat-regulating hormone insulin and increased fat burning as expected, whereas fat restriction had no observed changes in insulin production or fat burning. The research was conducted at the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. Results were published August 13 in Cell Metabolism.

“Compared to the reduced-fat diet, the reduced-carb diet was particularly effective at lowering insulin secretion and increasing fat burning, resulting in significant body fat loss,” said Kevin Hall, Ph.D., NIDDK senior investigator and lead study author. “But interestingly, study participants lost even more body fat during the fat-restricted diet, as it resulted in a greater imbalance between the fat eaten and fat burned. These findings counter the theory that body fat loss necessarily requires decreasing insulin, thereby increasing the release of stored fat from fat tissue and increasing the amount of fat burned by the body.”

The researchers studied 19 non-diabetic men and women with obesity in the Metabolic Clinical Research Unit at the NIH Clinical Center in Bethesda, Maryland. Participants stayed in the unit 24 hours per day for two extended visits, eating the same food and doing the same activities. For the first five days of each visit they ate a baseline balanced diet. Then for six days, they were fed diets containing 30 percent fewer calories, achieved by cutting either only total carbs or total fat from the baseline diet, while eating the same amount of protein. They switched diets during the second visit.

The researchers had previously simulated the study with a math model of human metabolism, whose body fat predictions matched the data later collected in the study. When simulating what might happen over longer periods, the model predicted relatively small differences in body fat loss with widely varying ratios of carbs to fat. Those results suggest the body may eventually minimize differences in body fat loss when diets have the same number of calories. More research is needed to assess the physiological effects of fat and carb reduction in the long term.

“This NIH study provides invaluable evidence on how different types of calories affect metabolism and body composition,” said NIDDK Director Griffin P. Rodgers, M.D.  “The more we learn about the complicated topic of weight loss, the better we can find ways to help people manage their health.”

More than two-thirds of American adults are overweight or obese. Maintaining a healthy weight can help prevent complications related to overweight and obesity such as heart disease, type 2 diabetes and certain types of cancer, some of the leading causes of preventable death.

“Our data tell us that when it comes to body fat loss, not all diet calories are exactly equal,” Hall said. “But the real world is more complicated than a research lab, and if you have obesity and want to lose weight, it may be more important to consider which type of diet you’ll be most likely to stick to over time.”

The NIDDK, a component of the NIH, conducts and supports research on diabetes and other endocrine and metabolic diseases; digestive diseases, nutrition and obesity; and kidney, urologic and hematologic diseases. Spanning the full spectrum of medicine and afflicting people of all ages and ethnic groups, these diseases encompass some of the most common, severe and disabling conditions affecting Americans. For more information about the NIDDK and its programs, visit http://www.niddk.nih.gov.

About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.

NIH…Turning Discovery Into Health®

###

Institute/Center

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Contact

Krysten Carrera
301-496-3583

Multimedia

Carbs vs Fat in the Diet – Kevin Hall, NIH

Carbs vs Fat in the Diet – Kevin Hall, NIH

Connect with Us

  • Subscribe to news releases
  • RSS Feed

Connect with Us

  • Contact Us
  • X
  • Facebook
  • Instagram
  • YouTube
  • Flickr
  • More Social Media from NIH

Footer

  • NIH Home
  • Virtual Tour
  • En Español
  • Visitor Information
  • Frequently Asked Questions
  • Privacy Policy
  • Disclaimers
  • Accessibility
  • NIH Website Archives
  • Nondiscrimination Notice
  • Freedom of Information Act
  • No Fear Act
  • HHS Vulnerability Disclosure
  • Office of Inspector General
  • USA.gov

NIH…Turning Discovery Into Health®

National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892

U.S. Department of Health and Human Services

Back to Top