• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
The BarBend Logo in white.

BarBend

The Online Home for Strength Sports

  • News
    • CrossFit
    • Strongman
    • Bodybuilding
    • Powerlifting
    • Weightlifting
    • HYROX
  • Reviews
    • Recovery
      • Best Cold Plunges
      • Best Saunas
      • Best Mini-Massage Guns
    • Supplements
      • Best Protein
        • Best Vegan Protein Powders
        • Best Whey Isolate Protein Powders
        • Best Mass Gainer
        • Best Protein Bars
      • Best Pre-Workouts
        • Best Pre-Workout for Women
        • Best Pre-Workouts for Men
        • Best Non-Stim Pre-Workouts
        • Strongest Pre-Workouts
      • Best Creatine
      • Best Electrolyte Supplements
      • Best Greens Powder
      • Best Meal Replacements
      • Best Nitric Oxide Supplements
      • Best Fat Burners
      • Individual Supplement Reviews
    • Cardio Equipment
      • Best Treadmills
      • Best Rowing Machines
      • Best Exercise Bikes
      • Best Ellipticals
      • Best Recumbent Bikes
      • Individual Cardio Equipment Reviews
    • Strength Equipment
      • Best Adjustable Dumbbells
      • Best Dumbbells
      • Best Kettlebells
      • Best Barbells
      • Best Squat Racks
      • Best Weight Benches
      • Best Resistance Bands
      • Best Leg Extension Machines
      • Individual Strength Equipment Reviews
    • Apparel
      • Best Weightlifting Shoes
      • Best Cross Training Shoes
      • Best Running Shoes
      • Best Gym Shorts
    • Fitness Tech
      • Best Running Apps
      • Best Fitness Trackers
      • Best Workout Apps
      • Best Smart Scales
    • Support Gear
      • Best Lifting Straps
      • Best Gym Bags
      • Best Lifting Gloves
      • Best Wrist Wraps
  • Nutrition
    • Diets
      • Carb Cycling
      • Vertical Diet
      • Reverse Dieting
      • Carnivore Diet
      • Ketogenic Diet
      • Intermittent Fasting
      • IIFYM Diet
    • Muscle Gain
      • How to Dirty Bulk
      • Go From Cutting to Bulking
      • Eat These Carbs
      • How to Eat for Muscle
    • Fat Loss
      • Macros for Fat Loss
      • Calorie Deficits
      • Natural Fat Burners
      • Cut 2 Pounds Weekly
    • Supplement Guides
      • Pre-Workout
      • Whey Protein
      • Mass Gainers
      • Greens Powders
      • Creatine
      • BCAAs
    • Daily Protein Needs
    • Pre- and Post-Workout Nutrition
    • Foods With Creatine
    • Bulking Tips
  • Training
    • Exercise Guides
      • Deadlift
      • Bench Press
      • Back Squat
      • Overhead Press
      • Lat Pulldown
      • Shoulder Exercises
      • Chest Exercises
      • Ab Exercises
      • Quad Exercises
      • Biceps Exercises
    • Training Guides
      • Beginner’s Guide to the Gym
      • How to Build Muscle
      • Guide to Muscle Hypertrophy
      • How to Train on a Cut
    • Workouts
      • Back Workouts
      • At-Home Workouts
      • Chest & Back Workouts
      • Full-Body Workout
      • HIIT Workouts
      • Bodybuilding Workouts
      • Farmer’s Carry Workouts
    • Programs
      • 5×5 Program
      • Bodybuilding Programs
      • Push-Up Program
      • Pull-Up Program
      • 5/3/1 Program
      • Powerbuilding Program
      • German Volume Training
      • Build Your Own Program
  • Calculators
    • Protein Intake Calculator
    • Macros Calculator
    • BMR Calculator
    • Squat Calculator
    • Calorie Calculator
  • Community Forum
Home » News » Recent Study Suggests Intermittent Fasting May Increase Mortality Risk by 91%. Should You Be Worried?

Recent Study Suggests Intermittent Fasting May Increase Mortality Risk by 91%. Should You Be Worried?

A recent report from the American Heart Association warns of the health risks associated with "time-restricted feeding." Here's what you need to know.

Written by Jake Dickson, NASM-CPT, USAW-L2
Last updated on November 20th, 2024

For about a decade now, the practice of intermittent fasting — a type of time-restricted feeding that typically entails fasting for around 16 hours of every 24-hour day — has been a popular method for bodybuilders, strength athletes, or anyone seeking to lose body fat. The allure is simple enough; past science has found that “IF” may have compelling weight management and general health benefits. (1)(2)

But the tide might be turning for intermittent fasting. On Mar. 18, 2024, the American Heart Association (AHA) highlighted an in-review study with a shocking headline: That time-restricted feeding may increase your risk of cardiovascular mortality by as much as 91%. You may have seen this news on outlets like WebMD and USA Today. 

A bodybuilder drinking meal replacement shake.
Credit: Egora_Shmanko / Shutterstock

[Related: Best Fat Burners]

But what exactly did the study say, do its claims hold water, and what are the associated health risks for intermittent fasting, if any? Here’s what you need to know.

Editor’s Note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. When starting a new training regimen and/or diet, it is always a good idea to consult with a trusted medical professional. We are not a medical resource. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. They are not substitutes for consulting a qualified medical professional.

What the Study Says

The research in question was presented at a Mar. 18-21 AHA conference and was helmed by Dr. Victor Wenze Zhong. (3) Here’s a more detailed look at the claims made by Dr. Zhong and colleagues: 

Findings

This research report was created based off of longitudinal, observational data of 20,078 adults. Please note that the full research text is not available as of the time of this article’s publication. The authors compared information on dietary patterns from 2003 to 2018 against data on U.S. deaths from 2003 to 2019. Their primary findings include:

  • Those who adhered to time-restricted eating, consuming all their calories within an eight-hour window, had a 91% higher risk of death due to cardiovascular disease.
  • The authors indicated that a similar increase exists for people living with heart disease or certain cancers.
  • For people currently living with cardiovascular disease, a “feeding window” of eight-10 hours per day was associated with a 66% higher risk of death from either heart disease or stroke.
  • Time-restricted feeding did not reduce overall risk of death.
  • A feeding window at or above 16 hours per day was associated with lower cancer mortality for cancer patients. 

Editor’s Note: The two sources of data utilized by Zhong et al. were the National Health and Nutrition Examination Surveys (NHANES) and the CDC’s National Death Index database. 

Limitations

Before you go revamping your entire meal prep plan, know that there are plenty of limitations to the arguments presented by Dr. Zhong and the AHA. While scientific data is always valuable to have, there are some limitations to this study that you should be aware of.

First and foremost, per the AHA itself, “…[limitations] included reliance on self-reported dietary information.” This means that the information obtained from this research came from subjects (over the age of 20) responding to surveys and not from participants in controlled settings or from a more stringently selected population. Moreover…

  • The full research text has yet to be published or peer-reviewed in an academic journal. 
  • This is observational, longitudinal (measured over time) data, which doesn’t present an especially strong causative relationship.
  • Subjects were “tracked” for a median period of eight years, reporting only on their dietary behaviors.
  • Their data displayed a significant risk of cardiovascular mortality, but their data showed no significant negative impact on all-cause mortality from fasting. 
https://www.youtube.com/watch?v=z2fFOSPJe3U

[Related: The Ultimate Guide to Pre-Workout Supplements]

This presentation from the AHA has drawn criticism from a number of different sources. Speaking to WebMD, Dr. Christopher Gardner, a professor of medicine at Stanford University, regarded the conclusions as “premature and misleading.”

Notably, leading author Dr. Zhong also remarked to WebMD about the limitations of his team’s work. “[Multi-year controlled dietary trials are] challenging if not impossible to conduct,” he said, indicating that the absence of evidence on long-term intermittent fasting behaviors means that people should be “extremely cautious.”

What You Should Do

So, what should you do with this information if you’re an IF devotee? Is it time to hang up the lifting belt and get back into breakfast? Not necessarily. While the headline associated with this report is more shocking than most scientific claims, Dr. Zhong’s work has faced some backlash from the scientific community. More importantly, the purported risks have yet to be substantiated by more credible research methods.

https://www.youtube.com/watch?v=s_jfevHRpqQ

[Related: The Best Protein Powders for Women]

Intermittent fasting is an accessible, often-effective method of weight management, but it’s hardly a one-size-fits-all dietary approach. If you enjoy practicing IF (or any of its cousins), you shouldn’t let this single data set dissuade you. That said, there’s more than one effective type of diet out there. 

Other Types of Diets To Try

There’s no magic behind intermittent fasting; setting distinct “start eating” and “stop eating” times can help people control their caloric intake, which is a method for effecting weight change. But if intermittent fasting isn’t your jam, you may consider trying another dietary protocol with methods that better align with your habits and goals:

  • Warrior Diet
  • Flexible Dieting
  • Mediterranean Diet
  • Keto Diet
  • Carnivore Diet

Note that “specialty” diets, including but not limited to the ones mentioned above, are not necessarily designed to replicate the benefits of intermittent fasting. Not all dietary protocols are suitable for all individuals. The eating behavior that you select should be sustainable, fulfilling, aligned with your health goals, and, most importantly, supported by scientific evidence. 

More Research Content

  • Research Suggests That Today’s Children Are Weaker Than Previous Generations
  • Study: Standing Calf Raises Build More Than 2x as Much Muscle as Seated
  • This Study Suggests That Even 100 Grams of Protein Per Meal Isn’t “Wasted”

References

  1. Halberg, N., Henriksen, M., Söderhamn, N., Stallknecht, B., Ploug, T., Schjerling, P., & Dela, F. (2005). Effect of intermittent fasting and refeeding on insulin action in healthy men. Journal of applied physiology (Bethesda, Md. : 1985), 99(6), 2128–2136. 
  2. Tinsley, G. M., Forsse, J. S., Butler, N. K., Paoli, A., Bane, A. A., La Bounty, P. M., Morgan, G. B., & Grandjean, P. W. (2017). Time-restricted feeding in young men performing resistance training: A randomized controlled trial. European journal of sport science, 17(2), 200–207. 
  3. 8-hour time-restricted eating linked to a 91% higher risk of cardiovascular death. American Heart Association. (n.d.)

Featured Image: grandbrothers / Shutterstock

About Jake Dickson, NASM-CPT, USAW-L2

Jake is a graduate of the University of North Carolina at Wilmington with a B.S. in Exercise Science. He began his career as a weightlifting coach before transitioning into sports media to pursue his interest in journalism.

View All Articles

Primary Sidebar

Latest Reviews

Featured image for the Ironmaster Super Bench Pro V2 Review

Ironmaster Super Bench Pro V2 Review (2025): Our Expert’s New Favorite FID Bench

Titan T3 Power Rack Review

Titan T3 Power Rack Review (2025): An Expert-Approved Rig Beckoning to Budget-Minded Athletes

Our tester works out at the beach in preparation for the Rogue Resistance Bands Review

Rogue Resistance Bands Review (2025): Tested by a Certified Personal Trainer

Barbend tester Jake Herod works out on a Force USA Trainer

Force USA G3 Review (2025): Our Experts Tested This Compact All-In-One Rack for Small Home Gyms

BarBend

BarBend is an independent website. The views expressed on this site may come from individual contributors and do not necessarily reflect the view of BarBend or any other organization. BarBend is the Official Media Partner of USA Weightlifting.

  • About Us
  • Advertise With Us
  • Contact Us
  • Facebook
  • Instagram
  • Twitter
  • YouTube
  • Pinterest

Sections

  • CrossFit
  • Strongman
  • Bodybuilding
  • Powerlifting
  • Weightlifting
  • Reviews
  • Nutrition
  • Training

More

  • BarBend Newsletter
  • BarBend Podcast
  • The Ripped Report
  • 1RM Calculator
  • BMR Calculator
  • Macros Calculator
  • Protein Calculator
  • Squat Calculator

Policies

  • Accessibility
  • Advice Disclaimer
  • Cookies Policy
  • Disclaimers
  • Disclosures
  • Editorial Policy
  • Privacy Policy
  • Terms of Use

Copyright © 2025 · BarBend Inc · Sitemap