Skipping meals is a common weight-loss tactic, from skipping breakfast to full intermittent fasting. Two large reviews of randomised trials give a clearer picture than headlines do.
Skipping breakfast
A 2020 meta-analysis in Obesity pooled seven randomised trials (425 adults, average length 8.6 weeks). Compared with eating breakfast, skipping it reduced body weight by about 0.54 kg. Percent body fat did not differ significantly. In three trials that reported LDL cholesterol, breakfast skippers had higher LDL by about 9 mg/dL. The authors concluded that breakfast skipping may have a modest effect on weight loss and may raise LDL in the short term, and that more studies are needed.
Intermittent fasting
A 2025 network meta-analysis in the BMJ covered 99 randomised trials with 6,582 adults. All intermittent fasting and continuous energy restriction strategies reduced body weight compared with eating freely. Compared with continuous energy restriction, alternate-day fasting was the only fasting strategy that showed an additional benefit, about 1.29 kg more weight loss, mostly in shorter trials. Overall, the authors found intermittent fasting had similar benefits to continuous energy restriction for weight loss and cardiometabolic risk factors.
The takeaway
- Eating fewer calories is what drives weight loss. How you schedule meals is a matter of what you can stick to.
- Skipping breakfast is not harmful for everyone, but it may raise LDL in the short term.
- People with diabetes, a history of disordered eating, or who are pregnant should talk to a doctor before fasting.
Frequently asked questions
Will skipping breakfast help me lose weight?
In seven randomised trials, skipping breakfast reduced body weight by about 0.54 kg on average, a modest effect.
Is intermittent fasting better than regular dieting?
The 2025 BMJ review found similar benefits to continuous energy restriction overall, with alternate-day fasting showing a small extra benefit in shorter trials.
Does skipping breakfast affect cholesterol?
In three trials, LDL cholesterol was higher in breakfast skippers by about 9 mg/dL in the short term.
References
- Bonnet JP et al. (2020). Breakfast Skipping, Body Composition, and Cardiometabolic Risk: A Systematic Review and Meta-Analysis of Randomized Trials. Obesity (Silver Spring). PubMed 32304359
- Semnani-Azad Z et al. (2025). Intermittent fasting strategies and their effects on body weight and other cardiometabolic risk factors: systematic review and network meta-analysis of randomised clinical trials. BMJ. PubMed 40533200
General information, not medical advice. Talk to your doctor before changing your diet or exercise routine. Last updated 27 October 2026.
