Don’t expect skipping breakfast or the 16:8 intermittent fasting method to help you control your weight; instead, pick a meal timing you can stick to long-term

There’s no monetary cost. What you save is the mental energy you’d otherwise spend worrying about meal timing.

Let’s first address the claim that skipping breakfast causes people to eat more later in the day. One meta-analysis combined data from 13 randomized trials. Participants assigned to eat breakfast consumed 259.79 kcal more per day on average than those who skipped it (95% CI 78.87–440.71). Their body weight was also 0.44 kg higher (95% CI 0.07–0.82). However, people who skipped breakfast did not make up for those missing calories at subsequent meals. All these trials had very short follow-up periods: an average of 7 weeks for weight tracking, and just 2 weeks for measuring calorie intake. Next, we look at 16:8 intermittent fasting, which restricts eating to a specific window each day. One trial involved 116 overweight adults over 12 weeks. The group limited their eating to 12 p.m. to 8 p.m. showed no significant weight difference compared to those eating three regular meals daily: a difference of −0.26 kg (95% CI −1.30 to 0.78). Another trial conducted in Guangzhou followed 139 obese patients for 12 months. Those who combined time-restricted eating with calorie restriction lost 1.8 kg more on average than those only controlling calorie intake (95% CI −4.0 to 0.4), a difference that also failed to reach statistical significance. Finally, we examine whether long-term breakfast skipping is harmful. A pooled analysis of 2.38 million people found more cardiovascular disease among breakfast skippers: odds ratio OR 1.17 (95% CI 1.09–1.26). Deaths from cardiovascular disease were also more common: odds ratio OR 1.49 (95% CI 1.20–1.84). These findings come from observational studies that did not assign participants to breakfast or non-breakfast groups. One original study with 17–23 years of follow-up reported an all-cause mortality hazard ratio (HR) of 1.19 for breakfast skippers (95% CI 0.99–1.42), a figure that crosses 1 but is not statistically significant.

Sievert K, Hussain SM, Page MJ, 等 (2019). Effect of breakfast on weight and energy intake: systematic review and meta-analysis of randomised controlled trials. BMJ. https://doi.org/10.1136/bmj.l42；Lowe DA, Wu N, Rohdin-Bibby L, 等 (2020). Effects of Time-Restricted Eating on Weight Loss and Other Metabolic Parameters in Women and Men With Overweight and Obesity. JAMA Internal Medicine. https://doi.org/10.1001/jamainternmed.2020.4153；Liu D, Huang Y, Huang C, 等 (2022). Calorie Restriction with or without Time-Restricted Eating in Weight Loss. New England Journal of Medicine. https://doi.org/10.1056/NEJMoa2114833；Zhang H, Zhang S, Liu Y, 等 (2025). The association between skipping breakfast and cardiovascular disease: a meta analysis. Frontiers in Cardiovascular Medicine. https://doi.org/10.3389/fcvm.2025.1565806；Rong S, Snetselaar LG, Xu G, 等 (2019). Association of Skipping Breakfast With Cardiovascular and All-Cause Mortality. Journal of the American College of Cardiology. https://doi.org/10.1016/j.jacc.2019.01.065；Fernandes-Alves D, Teixeira GP, Guimarães KC, Crispim CA (2026). Systematic Review and Meta-analysis of Randomized Clinical Trials Comparing Time-Restricted Eating With and Without Caloric Restriction for Weight Loss. Nutrition Reviews. https://doi.org/10.1093/nutrit/nuaf053；Sun T, Zhang L, Lu Y, 等 (2024). Non-linear relationship between the first meal time of the day and gallstone incidence in American adults. Frontiers in Nutrition. https://doi.org/10.3389/fnut.2024.1521707；Liu T, Wang Y, Wang X, 等 (2023). Habitually Skipping Breakfast Is Associated with the Risk of Gastrointestinal Cancers: Evidence from the Kailuan Cohort Study. Journal of General Internal Medicine. https://doi.org/10.1007/s11606-023-08094-7；National Institute of Diabetes and Digestive and Kidney Diseases (2022). Symptoms & Causes of Peptic Ulcers (Stomach or Duodenal Ulcers)（「The most common causes of peptic ulcers are Helicobacter pylori (H. pylori) infection and nonsteroidal anti-inflammatory drugs (NSAIDs).」）. https://www.niddk.nih.gov/health-information/digestive-diseases/peptic-ulcers-stomach-ulcers/symptoms-causes

Controversy. Those two cardiovascular odds ratios comes from record-only, non-randomized studies. Breakfast skippers are already more likely to smoke, drink, sit long, and earn less; those factors cannot be cleaned up fully. So how much of the association is caused by breakfast itself is unclear. The all-cause-death result already crosses 1. 16:8 is also disputed. One pool of 30 trials and 1341 people, with both arms eating the same amount, found time-restricted eating lost 1.46 kg more (−2.65 to −0.26). The cost was 0.41 kg more lean mass lost. But most of those trials were short; the longest, strictest twelve-month trial said no difference. Long fasting also links to the gallbladder. In a cross-sectional survey of 6547 people, each hour later the first meal of the day was associated with an odds ratio OR 1.05 for detected gallstones (1.02–1.08). For a first meal between 9:00 and 14:00 versus earlier, the odds ratio was OR 1.49 (1.24–1.77). The mechanism is that the longer bile sits in the gallbladder, the more easily stones form. But this is a same-time survey; gallbladder problems may have changed meal habits first. China’s Kailuan cohort followed 5.6 years and recorded 369 digestive-tract cancers. Breakfast skippers had 2.32 times the colorectal-cancer risk (1.34–4.01) and 5.43 times gallbladder and extrahepatic bile-duct cancer (1.34–21.93). The latter’s credible range reaches 21.93 — too few events; treat as a lead only. Altogether, for weight control, meal timing’s effect is small; don’t spend mental effort on it. Whether long-term total breakfast skipping is good: existing evidence is all association, not proof of cause, but the direction leans unfavorable. To be safe, eat normally; just don’t expect it to help you lose weight. An NIDDK public page states the most common causes of stomach ulcers are Helicobacter pylori and painkillers such as aspirin and ibuprofen; fasting is not among the rarer causes listed. What to check: Section 1, Item 23 (test for H. pylori; if positive, eradicate). Gallstones found on check-up that never hurt: Item 20 in this section. To control weight, what has evidence is what and how much you eat — Section 2, Item 27 (5 servings of fruit and vegetables a day), Item 28 (less ultra-processed food), and Item 32 (keep BMI 20–25). People with diabetes, on glucose-lowering drugs, or pregnant are exceptions; missing a meal may mean low blood sugar — follow medical advice. Extreme fasting and purging are separate — Section 28, Item 1 (don’t use extreme dieting, fasting, or purging to control weight).