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 related to “time-restricted feeding.” Here’s what it’s worthwhile to know.

For a couple of decade now, the practice of intermittent fasting — a style of time-restricted feeding that typically entails fasting for around 16 hours of each 24-hour day — has been a preferred method for bodybuilders, strength athletes, or anyone in search of to lose body fat. The allure is easy enough; past science has found that “IF” could have compelling weight management and general health advantages. (1)(2)

But the tide is perhaps 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 could have seen this news on outlets like WebMD and .

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

Editor’s Note: BarBend

What the Study Says

The research in query was presented at a Mar. 18-21 AHA conference and was helmed by Dr. Victor Wenze Zhong. (3) Here’s a more detailed take a 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 just not available as of the time of this text’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 inside an eight-hour window, had a 91% higher risk of death on account of heart problems.
• The authors indicated that a similar increase exists for people living with heart disease or certain cancers.
• For people currently living with heart problems, a “feeding window” of eight-10 hours per day was related to 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 related to lower cancer mortality for cancer patients.

The two sources of knowledge 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  of limitations to the arguments presented by Dr. Zhong and the AHA. While scientific data is at all times priceless to have, there are some limitations to this study that you have to be aware of.

First and foremost, per the AHA itself, “…[limitations] included reliance on self-reported dietary information.” This implies that the knowledge obtained from this research got here from subjects (over the age of 20) responding to surveys and never from participants in controlled settings or from a more stringently chosen population. Moreover…

• The full research text has yet to be published or peer-reviewed in an educational journal.
• This is observational, longitudinal (measured over time) datawhich 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 big risk of cardiovascular mortality, but their data showed no significant negative impact on all-cause mortality from fasting.

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

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

What You Should Do

So, what do you have to do with this information in the event you’re an IF devotee? Is it time to hold up the lifting belt and get back into breakfast? Not necessarily. While the headline related to 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.

Intermittent fasting is an accessible, often-effective approach to weight management, nevertheless 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 multiple effective style of food plan on the market.

Other Types of Diets To Try

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

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

More Research Content

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 motion 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.)