3 Intermittent Fasting Outperforms Traditional Dieting for Weight Loss

We all know the traditional approach to dieting — restricting calories to lose weight. It’s a method that’s stood the test of time. But what if there’s a more effective way? New research from the University of Colorado Anschutz Medical Campus suggests that a specific intermittent fasting regimen, known as 4:3 intermittent fasting (IMF), might actually be more effective than traditional calorie restriction for weight loss.

In this study, researchers compared two groups of participants over the course of 12 months to determine which weight loss method yielded the best results. The participants, aged 18 to 60, had a BMI between 27 and 46, meaning they were considered overweight or obese by the Centers for Disease Control and Prevention (CDC).

The first group followed the traditional daily caloric restriction (DCR) approach, while the second group adhered to the 4:3 intermittent fasting method. In the 4:3 regimen, participants ate freely on four days a week and practiced intense calorie restriction on the remaining three days.

After a year, the intermittent fasting group reported an average body weight loss of 7.6%, compared to 5% in the daily calorie-restricted group. The study, published in the journal Annals of Internal Medicine, concluded that 4:3 intermittent fasting resulted in a “modestly greater weight loss” for those with overweight or obesity.

Understanding the Difference: IMF vs. Time-Restricted Eating (TRE)

So, what exactly is 4:3 intermittent fasting? In an interview with Fox News Digital, study co-authors Danielle Ostendorf and Victoria Catenacci explained the distinction between IMF and another popular dieting strategy, time-restricted eating (TRE).

“IMF involves cycling between complete or near-complete (over 75%) energy restriction on ‘fast’ days and energy intake on non-fast days,” they said. “On the other hand, TRE involves limiting the daily window of food intake to 8 to 10 hours on most days of the week—examples include 16/8 or 14/10 protocols.”

The participants in the 4:3 IMF group were required to consume about 80% fewer calories on fast days compared to their usual energy requirements. For women, this meant consuming roughly 400 to 600 calories, while men had a target of 500 to 700 calories.

How It Works: The 4:3 IMF Plan in Action

On the three fasting days each week, participants consumed just 400 to 600 calories for women and 500 to 700 calories for men. The fast days were spread out, and couldn’t all be consecutive. On the four non-fast days, participants were encouraged to eat freely, but healthy food choices were strongly recommended.

According to Ostendorf, “This study shows that 4:3 intermittent fasting is a highly effective and safe weight loss strategy and can be considered as a viable option among other evidence-based approaches.”

Why Intermittent Fasting Works: Flexibility Meets Effectiveness

What makes 4:3 IMF stand out from traditional calorie-restricted diets? The key lies in the balance of rigidity and flexibility. The fast days are tough but manageable, and the non-fast days allow participants to enjoy their favorite foods without the constant pressure of calorie counting.

Ostendorf, reflecting on the results, said, “We were somewhat surprised to see that our data didn’t align with other studies on intermittent fasting versus calorie restriction. But after seeing the results, we believe that three days of fasting is the sweet spot—it’s not too rigid but still very effective.”

How to Get Started with 4:3 IMF: A Beginner’s Guide

If you’re curious about trying the 4:3 intermittent fasting method, Ostendorf recommends starting slowly. “Try one fasting day at first—consuming about 500 calories—and then gradually add more fasting days as your body adapts,” she advises.

It’s important to note that participants in the study were provided with behavioral support from a registered dietitian. While this guidance was valuable, Ostendorf acknowledged that not everyone has access to a dietitian. She suggests seeking support from trusted resources or health professionals if possible.

For those considering intermittent fasting, it’s also crucial to stay hydrated on fast days with non-caloric beverages like black coffee, sparkling water, or herbal teas. Ostendorf also encouraged the use of water-based drinks to curb hunger during fasting periods.

What’s Next for Intermittent Fasting Research?

While the 4:3 IMF method has shown promising results, researchers note that more research is needed to evaluate its safety and efficacy across different populations. The study’s authors are especially interested in exploring the effects of intermittent fasting on people with specific health conditions such as diabetes, cardiovascular disease, and pregnancy.

They also hope to conduct a long-term follow-up study to identify which individuals are most likely to benefit from intermittent fasting. This would allow for more personalized recommendations in the future.

3 Intermittent Fasting Might Be the Right Diet for You

4:3 intermittent fasting resulted in modestly greater weight loss (7.6%) compared to traditional daily caloric restriction (5%) in adults with obesity or overweight.
The method involves eating freely on four days and fasting with intense calorie restriction on three non-consecutive days.
While the study showed 4:3 IMF’s effectiveness, it’s important to consult with a healthcare professional before starting any new diet plan, especially if you have underlying health conditions.
Starting slow and gradually increasing fasting days can help your body adjust to the 4:3 IMF method.

FAQs: Everything You Need to Know About 4:3 Intermittent Fasting

What is 4:3 intermittent fasting? 4:3 intermittent fasting involves eating freely on four days of the week and fasting with intense calorie restriction on three non-consecutive days. This method has shown to be more effective for weight loss than traditional daily caloric restriction.
How many calories should I eat on fast days? On fast days, women should consume approximately 400-600 calories, and men should aim for 500-700 calories. The goal is to consume around 80% fewer calories than your normal intake.
Can I eat anything on non-fast days? Yes, you can eat freely on non-fast days, but it’s recommended to make healthy food choices to maximize the benefits of intermittent fasting.
What are the benefits of 4:3 intermittent fasting? The key benefits include modestly greater weight loss, flexibility in your diet, and an overall safe and effective approach to losing weight compared to traditional calorie restriction.
Should I consult a doctor before starting intermittent fasting? Yes, it’s always best to consult with a healthcare provider before starting any diet plan, especially if you have underlying health conditions or concerns.
Is 4:3 intermittent fasting suitable for everyone? While promising, intermittent fasting may not be suitable for certain groups, including pregnant women, children, older adults, and individuals with chronic health conditions. Always seek professional advice before starting.