Is Breakfast Still the Most Important Meal of the Day?

Few pieces of dietary wisdom are repeated as often as the claim that breakfast is the most important meal of the day. It promises energy, focus and a faster metabolism, and warns that skipping the morning meal will leave you sluggish and prone to weight gain. Yet a growing body of research suggests the picture is far more nuanced — and that whether breakfast deserves its crown depends a great deal on the individual.

Where the slogan came from

The phrase owes much of its staying power to the 1960s American nutritionist Adelle Davis, who advised people to “eat breakfast like a king, lunch like a prince, and dinner like a pauper.” The idea took hold and never really let go. It has also been reinforced over the decades by food marketing, particularly from cereal makers with an obvious interest in seeing the morning meal elevated above the rest.

Today, surveys suggest that somewhere between 15% and 25% of adults regularly skip breakfast, even as many of them still consider it the meal they “should” be eating. That gap between belief and behaviour is a good reason to ask what the evidence actually shows.

What the research actually shows

Much of the case for breakfast rests on observational studies — research that tracks large groups over time and looks for patterns. These studies have linked regular breakfast eating with a lower risk of obesity, heart disease and certain other conditions. But observational data can show correlation, not cause. People who eat breakfast every day also tend to smoke less, exercise more and eat better overall, which makes it hard to isolate breakfast itself as the reason for their better health.

A 2021 study in Cancer Causes & Control found that people who skipped breakfast had a higher risk of death from any cause, including cancer. Yet the same paper cautioned that habitual breakfast-eaters may simply be more health-conscious in general — meaning the breakfast may be a marker of a healthy lifestyle rather than its cause. Randomised controlled trials, which are better at proving cause and effect, have produced far more mixed results on whether eating or skipping breakfast meaningfully changes body weight.

The case for eating breakfast

None of this means the “eat breakfast” advice is worthless. A balanced morning meal is a genuine opportunity to load up on nutrients many people struggle to fit in later — fibre, protein, calcium and key vitamins. Breakfast can also sharpen alertness, focus and mood in the hours that follow.

The evidence is strongest for children. Studies consistently show that kids who eat in the morning concentrate better and perform better at school — it is, as one dietitian put it, easier to focus when your stomach isn’t growling. For growing bodies and developing brains, a reliable morning meal carries real weight.

The case for skipping — and intermittent fasting

On the other side sits intermittent fasting, an eating pattern popularised over the past decade in which people confine eating to a set window — often around eight hours — and fast for the remaining 12 to 16, frequently pushing the first meal well past sunrise. A number of studies have associated this approach with weight loss and improvements in cardiometabolic health, which sits awkwardly with the notion that breakfast is indispensable.

The practical takeaway from this research is simple: if you don’t wake up hungry, there is little strong evidence that forcing down breakfast will benefit you. Delaying your first meal is a legitimate choice for many people.

The bottom line

Most nutrition experts now resist crowning any single meal as the most important. What matters far more is the overall quality of your diet and whether your nutrient needs are met across the day, whenever you happen to eat. If breakfast helps you eat well and feel good, keep it. If you’d rather wait, there’s little reason to feel guilty — provided the rest of your meals do the nutritional work.

Breakfast, in other words, may not be the most important meal of the day. But for many people it is still a useful one — and that, rather than the slogan, is the part worth holding on to.

A note on fasting: intermittent fasting is not recommended for everyone — including people with type 1 diabetes, those who are pregnant or breastfeeding, anyone with a history of disordered eating, and those who are underweight. This article is general information, not medical advice; check with a healthcare professional about what suits you.