Unlocking the Benefits of Intermittent Fasting for Heart Health and Weight Management

Intermittent fasting, also known as time-restricted eating, is a popular method that some people use to manage their weight.

This approach involves limiting the hours in which a person can eat, usually to an eight-hour window within a 24-hour period. During the remaining 16 hours, only clear liquids are consumed. Some variations of intermittent fasting include fasting for two or three days within a week or month.

How well does intermittent fasting work?

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In 2024, instead of focusing on dieting, consider trying time restriction for better health.

Previous studies have highlighted the benefits of time restriction. A review from December 2019 looked at both human and animal research and found that limiting calorie intake to a shorter period of the day can lead to improved longevity, lower blood pressure, and weight loss. However, it's worth noting that most of these studies were conducted on mice, and the human studies were relatively short, lasting only a few months.

New research published in April 2022 looked at 139 Chinese adults with varying degrees of weight issues. The study, which lasted a year, did not find any advantage to using a different method over calorie counting for losing weight or improving heart health.

Experts were quick to question and criticize recent research findings that proposed a link between eating within an eight-hour window or less and a 91% higher risk of dying from cardiovascular disease when compared to eating over a 12- to 16-hour period.

The preliminary research abstract, which has not yet undergone peer review or been published, was unveiled on Monday at a conference held by the American Heart Association in Chicago.

Empty plate with knife and fork on table

Empty plate with knife and fork on table

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Did you know that people who have stopped dieting have some interesting insights to share? According to a study conducted by senior study author Victor Wenze Zhong, a professor at the Shanghai Jiao Tong University School of Medicine in China, it was found that individuals who followed an 8-hour, time-restricted eating schedule were actually more likely to die from cardiovascular disease.

Zhong stated in a statement that our study's results suggest a need for dietary recommendations to be tailored to each person's health and the most current scientific research. It is important to note that the new findings are still in the early stages.

A recent study examined the eating habits of 20,000 individuals over a 24-hour period during their first year in a long-term health analysis of American adults. Researchers then reviewed death records in the following years.

The findings suggested a potential connection between limiting eating to an eight-hour window and an increased risk of death from cardiovascular disease. However, the study was unable to definitively conclude that this specific eating pattern directly caused the deaths, according to the authors.

Many experts have raised concerns about the latest research findings. Kevin McConway, a professor emeritus of applied statistics at The Open University in the United Kingdom, who was not part of the study, mentioned that the information provided in the conference abstract is insufficient to support the study's claims.

"The researchers grouped individuals into various dietary patterns based on their reported food intake over just two days, spanning an average study period of 8 years," stated McConway. "Attempting to connect these patterns to a prolonged time-restricted eating plan appears to be extrapolating beyond the available data."

Mixed salty snacks. Flat lay table scene on a rustic wood background.

Mixed salty snacks. Flat lay table scene on a rustic wood background.

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The abstract does not mention whether the individuals who were practicing time-restricted eating had jobs with unconventional hours, such as truck drivers, night shift workers, and healthcare professionals, according to Tom Sanders, a nutrition and dietetics professor emeritus at King’s College London who was not part of the research.

Sanders highlighted the significance of this information, noting that there is evidence linking these types of work schedules to a higher risk of developing type 2 diabetes and cardiovascular disease (CVD).

There is also no information in the abstract about tobacco and alcohol use, physical activity, or poverty level among those who said they practiced intermittent fasting, all of which are risk factors for heart disease, said Duane Mellor, a registered dietitian and senior teaching fellow at Aston Medical School in Birmingham, United Kingdom. Mellor was not involved in the study.

“We need to be very careful not to generate concerning headlines and stories based on such limited information,” Mellor said in a statement. “It is perhaps what you eat and your overall lifestyle that is more important than if you ate all your food in less than 8 hours on two days in the last decade.”

Eating only during a certain period of the day is the basis of time-restricted eating.

Eating only during a certain period of the day is the basis of time-restricted eating.

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Is intermittent fasting good for you?

In the world of science, research can sometimes lead to contradictory findings. This often happens because the quality of the study varies, and not all studies measure the same thing in the same manner.

When it comes to fasting, experts point out that studies show a wide range of results. Some research focuses on fasting for two or more days a week, while others look at fasting between 8 a.m. and 4 p.m., or from noon to 8 p.m., among other time frames.

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In a conversation with CNN's Chief Medical Correspondent Dr. Sanjay Gupta, nutrition researcher Christopher Gardner expressed his opinion that the data on intermittent fasting is not very convincing. He mentioned that studying and publishing clean results on this topic is a challenging task.

Gardner, a research professor of medicine at the Stanford Prevention Research Center, also highlighted the lack of emphasis on quality in intermittent fasting practices. He expressed concern that some individuals may misuse the concept of a fasting window by indulging in unhealthy food choices, such as a pint of ice cream or cookies, believing that the timing is the most important factor.

How to lose weight

What and how much you eat is more important than anything else, experts say.

Alice Lichtenstein, director and senior scientist at Tufts University’s Cardiovascular Nutrition Laboratory, emphasized that the key to weight loss and improving health markers like body fat, blood pressure, and glucose levels is to reduce calorie intake. She mentioned in an interview with CNN that it doesn't matter when you eat, as long as overall calorie intake is reduced.

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Moreover, a study conducted in September 2020, which is considered the gold standard of research, looked at 116 participants. The study found that there was no significant difference in weight loss between those who restricted their eating from 8 p.m. to noon the next day and those who did not.

A January observational study of 547 people also did not show any significant difference between restricting eating times and weight loss. CNN’s Madeline Holcombe, Scottie Andrew and Grace Walker helped with this report.

Editor's P/S:

The article delves into the topic of intermittent fasting, exploring its potential benefits and limitations. While some studies suggest that time-restricted eating can lead to improved longevity, lower blood pressure, and weight loss, other research raises concerns about its link to increased cardiovascular disease risk. The article emphasizes the need for more high-quality studies to determine the long-term effects of intermittent fasting.

Ultimately, the article concludes that the key to weight loss and improved health lies in reducing overall calorie intake rather than focusing solely on eating within a specific time frame. It highlights the importance of making healthy food choices and engaging in regular physical activity for sustainable weight management., including regular exercise and adequate sleep.