- Time-restricted eating, which restricts eating to specific hours of the day, did not impact weight among overweight adults with prediabetes or diabetes.
- Adults in the 12-week study ate the same healthy, pre-prepared foods, however, one group ate the bulk of their calories before 1 p.m. each day, versus the other group that ate 50% of their calories after 5 p.m.
Embargoed until 4 a.m. CT/5 a.m. ET, Monday, Nov. 9, 2020
DALLAS, Nov. 9, 2020 — Restricting meals to early in the day did not affect weight among overweight adults with prediabetes or diabetes, according to preliminary research to be presented at the American Heart Association’s Scientific Sessions 2020. The meeting will be held virtually, Friday, November 13 - Tuesday, November 17, 2020, and is a premier global exchange of the latest scientific advancements, research and evidence-based clinical practice updates in cardiovascular science for health care worldwide.
“We have wondered for a long time if when one eats during the day affects the way the body uses and stores energy,” said study author Nisa M. Maruthur, M.D., M.H.S., associate professor of medicine, epidemiology and nursing at Johns Hopkins University in Baltimore. “Most prior studies have not controlled the number of calories, so it wasn’t clear if people who ate earlier just ate fewer calories. In this study, the only thing we changed was the time of day of eating.”
Maruthur and colleagues followed 41 overweight adults in a 12-week study. Most participants (90%) were Black women with prediabetes or diabetes, and average age of 59 years. Twenty-one of the adults followed a time-restricted eating pattern, limiting eating to specific hours of the day and ate 80% of their calories before 1 p.m. The remaining 20 participants ate at usual times during a 12-hour window, consuming half of their daily calories after 5 p.m. for the entire 12 weeks. All participants consumed the same pre-prepared, healthy meals provided for the study. Weight and blood pressure were measured at the beginning of the study; then at 4 weeks, 8 weeks and 12 weeks.
The analysis found that people in both groups lost weight and had decreased blood pressure regardless of when they ate.
“We thought that the time-restricted group would lose more weight,” Maruthur said. “Yet that didn’t happen. We did not see any difference in weight loss for those who ate most of their calories earlier versus later in the day. We did not see any effects on blood pressure either.”
The researchers are now collecting more detailed information on blood pressure recorded over 24 hours, and they will be compiling this information with the results of a study on the effects of time-restricted feeding on blood sugar, insulin and other hormones.
“Together, these findings will help us to more fully understand the effects of time-restricted eating on cardiometabolic health,” Maruthur said. Co-authors are Scott Pilla, M.D., M.H.S.; May T.T. Maw, M.B.B.S.M., M.P.H.; Daisy Duan, M.D.; Di Zhao, Ph.D.; Eliseo Guallar, M.D., Dr. P.H.; Ruth Alma Turkson Ocran, Ph.D.; Karen White, M.S.; Beiwen Wu, M.S.P.H.; Jeanne Charleston, R.N.; Lawrence J. Appel, M.D., M.P.H.; and Jeanne M. Clark, M.D., M.P.H. Author disclosures are in the abstract. The study was funded by a grant from the American Heart Association.
- Multimedia, including a video perspective interview with Alexis C. Wood, Ph.D., chair of the writing group for the American Heart Association Scientific Statement: Caregiver Influences on Eating Behaviors in Young Children (May 2020), may be downloaded from the right column of the release link https://newsroom.heart.org/news/calories-by-the-clock?preview=b6fd89ef6b6c8a9bf6d448a9bf3ab580
- American Heart Association Nutrition Basics
- For more news at AHA Scientific Sessions 2020, follow us on Twitter @HeartNews #AHA20.
Statements and conclusions of studies that are presented at the American Heart Association’s scientific meetings are solely those of the study authors and do not necessarily reflect the Association’s policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. The Association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific Association programs and events. The Association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and biotech companies, device manufacturers and health insurance providers are available here, and the Association’s overall financial information is available here.
About the American Heart Association
The American Heart Association is a leading force for a world of longer, healthier lives. With nearly a century of lifesaving work, the Dallas-based association is dedicated to ensuring equitable health for all. We are a trustworthy source empowering people to improve their heart health, brain health and well-being. We collaborate with numerous organizations and millions of volunteers to fund innovative research, advocate for stronger public health policies, and share lifesaving resources and information. Connect with us on heart.org, Facebook, Twitter or by calling 1-800-AHA-USA1.
For Media Inquiries and AHA Expert Perspective:
AHA News Media in Dallas: 214-706-1173; firstname.lastname@example.org
Maggie Francis: 214-706-1382; Maggie.Francis@heart.org
For Public Inquiries: 1-800-AHA-USA1 (242-8721)