Is Intermittent Fasting More Effective for Weight-Loss Than Other Diets?

Check out this answer from Consensus:

Intermittent fasting is as effective as continuous calorie or energy restriction for weight loss and improving metabolic health. While IF may offer slight advantages in specific contexts, such as reducing waist circumference and improving insulin resistance, the overall effectiveness of IF and CER is comparable. The choice between IF and other dietary approaches should consider individual preferences, adherence potential, and lifestyle factors.

Intermittent fasting (IF) has gained popularity as a weight-loss strategy, often compared to continuous calorie restriction (CCR) or continuous energy restriction (CER). This synthesis examines whether IF is more effective for weight loss than other dietary approaches based on recent research findings.

Key Insights

• Weight Loss Effectiveness:
  • IF may lead to slightly more significant weight loss compared to CCR, although the difference is modest1 3 5.
  • Several studies found no significant difference in weight loss between IF and CER, suggesting that both methods are equally effective for weight reduction2 4 7 9.
• Body Composition:
  • IF and CER both result in similar reductions in fat mass and lean mass, indicating comparable effects on body composition4 9.
  • IF may be more effective in reducing waist circumference compared to non-intervention diets, but not significantly different from CER4 9.
• Glycemic Control and Metabolic Health:
  • IF and CER show similar improvements in glycemic control, fasting insulin, and lipid profiles in patients with type 2 diabetes and metabolic syndrome3 5 8.
  • IF may offer additional benefits in improving insulin resistance and blood lipid conditions compared to non-intervention diets4 10.
• Adherence and Long-term Efficacy:
  • Adherence to IF can be challenging, with significant dropout rates observed in long-term studies6.
  • Both IF and CER require sustained adherence for long-term effectiveness, and the choice of diet may depend on individual preferences and lifestyle compatibility6 9.

Is intermittent fasting more effective for weight-loss than other diets?

Ivor Ebenezer has answered Unlikely

An expert from University of Portsmouth in Neuroscience

Intermittent fasting (IF) normally refers to moderate or more prolonged periods of fasting interspersed by periods of eating and drinking. Most popular forms of IF include restricting food consumption to 500 or 600 calories for two or three days of the week, or fasting for one or two days a week. There are many other variations of IF. The results of numerous studies have indicated that intermittent fasting is no more effective for weight loss compared with other diets. Thus, for example, an analysis of clinical studies that compared the effects of IF with those of daily dietary restriction (where individuals restricted energy intake between 15 and 60 percent each day) on weight loss in obese subjects indicated that there was no significant differences between the two dieting paradigms at 3 and 12 weeks (Varady, K.A. 2011. Obesity Reviews, 12(7), e593-601). Interestingly, while most diets reduce weight with loss of both fat and lean (muscle) mass, it was found that intermittent fasting seems to have very little effect on lean mass. However, these data should be viewed with caution until further studies are carried out to confirm them. If these finding can be replicated, then retention of muscle mass would be a distinct advantage of IF over other diets.

 In summary, while intermittent fasting appears to be no more effective for weight loss compared with other diets, it should be noted that there may be differences in the way people respond to specific diets. Thus, some diets may be more effective in some individuals and others more effective in others.

Is intermittent fasting more effective for weight-loss than other diets?

Krista Varady has answered Unlikely

An expert from University of Illinois at Chicago in Fasting, Kinesiology

Many recent studies show that intermittent fasting produces the same amount of weight loss as daily calorie restriction diets. The main benefit of intermittent fasting is that individuals do not have to diet everyday to lose weight. They can diet every other day and still lose the same amount of weight as someone who was restricting calories daily.

Is intermittent fasting more effective for weight-loss than other diets?

Sharayah Carter has answered Unlikely

An expert from University of South Australia in Nutrition, Dietetics

Intermittent fasting (IF) is an alternative weight loss strategy becoming increasingly popular as it offers a reduced burden of dietary restriction by using severe energy restriction on some days of the week with unrestricted eating on others. The majority of the evidence suggests that IF is equally as effective for weight loss as a standard daily energy restriction (DER) (1-6). And so, for people who do not wish to restrict their intake on a daily basis, IF may be a suitable alternative weight loss method that is as effective but not superior to DER.

1.   Rynders, CA., et al. Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy Restriction for Weight Loss. Nutrients. 2019;11(10). 
2.   Harvie, M, Howell, A. Potential benefits and harms of intermittent energy restriction and intermittent fasting amongst obese, overweight and normal weight subjects – A narrative review of human and animal evidence. Behavi Sci. 2017;7(4):1-22.
3.   Headland, M., et al. Weight-Loss Outcomes: A Systematic Review and Meta-Analysis of Intermittent Energy Restriction Trials Lasting a Minimum of 6 Months. Nutrients. 2016;8(6):354.
4.     Davis, CS., et al. Intermittent energy restriction and weight loss: a systematic review. Eur J Clin Nutr. 2016;70(3):292-299.
5.   Seimon RV., et al. Do intermittent diets provide physiological benefits over continuous diets for weight loss? A systematic review of clinical trials. Mol Cell Endocrinol. 2015;418:153-172.

Is intermittent fasting more effective for weight-loss than other diets?

Rebecca Reynolds has answered Extremely Unlikely

An expert from UNSW Sydney in Psychology

There not one way to lose weight that will work for everyone, especially not in the long-term. Sorry, but there’s no universal magic bullet.

It’s important that each individual does what works best for him or her. And that is unlikely to be intermittent fasting for life – most people couldn’t commit to that.

Is intermittent fasting more effective for weight-loss than other diets?

Leanne Harris has answered Unlikely

An expert from University of Glasgow in Obesity

One issue when discussing intermittent fasting regimens is that currently there is no universally accepted definition. Intermittent energy restriction is the umbrella term which includes intermittent fasting. Intermittent fasting typically involves alternating a period of energy restriction (energy intake approximately 500–600 kcal), with a period of unrestricted or minimally restricted energy intake. Although this can include intakes of up to 800 kcal on fast days. There are a vast number of regimens published in the literature that claim to follow an intermittent fasting approach. The most commonly investigated include the 5:2 diet and alternative day fasting.

The current evidence on the effectiveness for intermittent fasting demonstrates that intermittent fasting is as effective as dieting every day for short term weight loss.

There isn’t a one-size-fits all approach to weight loss. The best weight loss approach is one that an individual can stick to as this will have the best results for them. There is a need for further research studies with longer follow-ups, to evaluate the long-term sustainability, adherence to, and safety of intermittent fasting weight management programmes.

Cioffi, I., Evangelista, A., Ponzo, V., Ciccone, G., Soldati, L., Santarpia, L., … & Bo, S. (2018). Intermittent versus continuous energy restriction on weight loss and cardiometabolic outcomes: a systematic review and meta-analysis of randomized controlled trials. Journal of translational medicine, 16(1), 371-386. (doi: 10.1186/s12967-018-1748-4)

Harris, L. et al. (2018) Intermittent fasting interventions for the treatment of overweight and obesity in adults aged 18 years and over: a systematic review and meta-analysis. JBI Database of Systematic Reviews and Implementation Reports, 16(2), 507-547. (doi:10.11124/JBISRIR-2016-003248)

Is intermittent fasting more effective for weight-loss than other diets?

Michelle Harvie has answered Unlikely

An expert from Manchester University Hospital Foundation NHS Trust in Breast Cancer, Fasting, Dietetics

Most trials show the same weight loss as other diets. But Intermittent fasting IS A GOOD VIABLE ALTERNATIVE FOR MANY PEOPLE