How long should you fast for weight loss?

July 15, 2020

Two daily fasting diets, also known as time-restricted feeding diets, are effective for weight loss, according to a new study published by researchers from the
The study reported results from a clinical trial that compared a 4-hour time-restricted feeding diet and a 6-hour time-restricted feeding diet to a control group.

"This is the first human clinical trial to compare the effects of two popular forms of time-restricted feeding on body weight and cardiometabolic risk factors," said Krista Varady, professor of nutrition at the UIC College of Applied Health Sciences and corresponding author of the story.

Participants in the 4-hour time-restricted feeding diet group were asked to eat only between the hours of 1 p.m. and 5 p.m. Participants in the 6-hour time-restricted feeding diet group were asked to eat only between the hours of 1 p.m. and 7 p.m.

In both the study groups, patients were allowed to eat whatever they wanted during the 4-hour or 6-hour eating period. During the fasting hours, participants were directed to only drink water or calorie-free beverages. In the control group, participants were directed to maintain their weight and not change their diet or physical activity levels.

The participants were followed for 10 weeks as weight, insulin resistance, oxidative stress, blood pressure, LDL cholesterol, HDL cholesterol, triglycerides and inflammatory markers were tracked.

The study, published in Cell Metabolism, found that participants in both daily fasting groups reduced calorie intake by about 550 calories each day simply by adhering to the schedule and lost about 3% of their body weight. The researchers also found that insulin resistance and oxidative stress levels were reduced among participants in the study groups when compared with the control group. There was no effect on blood pressure, LDL cholesterol, HDL cholesterol or triglycerides.

There also was no significant difference in weight loss or cardiometabolic risk factors between the 4-hour and 6-hour diet groups.

"The findings of this study are promising and reinforce what we've seen in other studies -- fasting diets are a viable option for people who want to lose weight, especially for people who do not want to count calories or find other diets to be fatiguing," Varady said. "It's also telling that there was no added weight loss benefit for people who sustained a longer fast -- until we have further studies that directly compare the two diets or seek to study the optimal time for fasting, these results suggest that the 6-hour fast might make sense for most people who want to pursue a daily fasting diet."
-end-
Varady and her colleagues also reported that there were no major adverse health events reported by study participants during the study and that the mild adverse events -- such as dizziness or headaches -- were limited to the beginning of the trial.

Co-authors on the study are UIC's Sofia Cienfuegos, Kelsey Gabel, Faiza Kalam, Mark Ezpeleta, Eric Wiseman, Vasiliki Pavlou, Shuhao Lin and Manoela Lima Oliveira. The study was supported by the National Institutes of Health (R01DK119783).

University of Illinois at Chicago

Related Weight Loss Articles from Brightsurf:

Weight loss shouldn't be the goal of PE
For adults, the goal of exercise is often to shed some pounds, but new research from the University of Georgia suggests the objective should be different for kids.

How long should you fast for weight loss?
Two daily fasting diets, also known as time-restricted feeding diets, are effective for weight loss, according to a new study.

Green tea may help with weight loss efforts
In an analysis published in Phytotherapy Research of randomized controlled trials, individuals who consumed green tea experienced a significant decline in body weight and body mass index.

Changing weight-loss strategies, attempts
The proportion of adults who tried to lose weight in the previous year increased from 1999 to 2016 but the findings of this observational study suggest the results may have been unsatisfactory.

Quality of life changes after weight loss
Obesity increases a number of adverse health consequences including reduced health-related quality of life.

Weight loss medicines underutilized by veterans
Despite the availability of new weight management medications and several clinical guidelines recommending their use as part of a comprehensive treatment plan for obesity, a new study has found that their use is extremely low (about one percent) among eligible Veterans.

Is the most effective weight-loss strategy really that hard?
Dietary self-monitoring is the best predictor of weight-loss success. But the practice is viewed as so unpleasant and time-consuming, many would-be weight-losers won't adopt it.

Study: Faster weight loss no better than slow weight loss for health benefits
Losing weight slowly or quickly won't tip the scale in your favor when it comes to overall health, according to new research.

Mindfulness training may help support weight loss
Mindfulness training may improve the effectiveness of intensive weight management programs, according to a small study published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism.

Does weight loss before surgery provide benefits?
For obese and overweight patients, it is common for various surgical procedures to be deferred until they have lost weight through diet and exercise.

Read More: Weight Loss News and Weight Loss Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.