EARLY ACCESS
Busted

Breakfast Is The Most Important Meal of the Day

Nutrition | December 14, 2025 | 2 sources

THE CLAIM

"Skipping breakfast will slow your metabolism and cause weight gain."

[EVIDENCE SUMMARY]

This popular belief originated from marketing campaigns by cereal companies in the early 1900s. Modern research shows that breakfast is not inherently more important than other meals. Intermittent fasting studies demonstrate that skipping breakfast does not harm metabolism. What matters is total daily nutrition quality and quantity, not mandatory morning eating.

The Origin of This Myth

The phrase 'breakfast is the most important meal of the day' was coined by James Caleb Jackson and John Harvey Kellogg in the late 19th century to promote their newly invented breakfast cereals. This was a marketing slogan, not a scientific conclusion.

What Science Actually Says

A 2019 systematic review in the BMJ analyzed 13 randomized controlled trials and found no evidence that eating breakfast helps weight loss or that skipping breakfast leads to weight gain. In fact, breakfast eaters consumed about 260 more calories per day on average.

Research Insight

Studies on intermittent fasting show that meal timing is flexible, and many people thrive without traditional breakfast.

  • Total daily calories matter more than breakfast specifically
  • Some people naturally prefer not eating in the morning
  • Intermittent fasting (skipping breakfast) can be healthy
  • Individual preferences and lifestyle should guide meal timing

[KEY TAKEAWAYS]

  • Breakfast importance was largely created by cereal marketing
  • Research does not support mandatory breakfast eating
  • Listen to your body and eat when you are genuinely hungry
  • Focus on overall diet quality rather than specific meal timing

[SOURCES] (2)

1

Effect of breakfast on weight and energy intake: systematic review

Sievert K, et al.

BMJ 2019 High credibility
View source →
2

Belief beyond the evidence: using the proposed effect of breakfast on obesity to show 2 practices that distort scientific evidence

Brown AW, et al.

American Journal of Clinical Nutrition 2013 High credibility
View source →

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