The idea of breakfast being the most important meal of the day could have been cooked up by a food manufacturer-but regardless of its origins, many studies are used to support this claim. The caveat, however, is that examining the long-term health outcomes in individuals who eat breakfast or skip it is a difficult task.
Instead, researchers have studied mostly the immediate effects of eating breakfast compared to skipping-what happens to your blood glucose? Are you more physically active when you eat breakfast? What other foods do you consume during the day if you eat breakfast or skip it?
Those finding are then used to infer what might happen over a lifetime of breakfast behavior. For example, if breakfast eaters are found to be more physically active, then we conclude (perhaps wrongly) that breakfast helps promote physical activity. But a recent study in Finland examined this question from a slightly different angle.
They categorized 1,854 adults by their chronotype. Your chronotype identifies you as a morning person-those who are earlier to bed and earlier to rise-or an evening person. They found that evening people tended to eat less in the morning compared to their morning peers, and more in the evening.
They especially ate more sugar, fat, and saturated fat at night, but interestingly they also consumed more sugar in the morning. They didn't study these individuals over a long period of time, and morning people had a slightly lower BMI compared to the evening people (27.1 vs 27.6) at the time of the study, so it's hard to say what the long-term effects are since they did not measure those.
Nevertheless, this study lends continued support that eating breakfast is at least associated with healthier characteristics like eating more fruit and being more active each day. However, the authors did use a novel approach to studying this concept by looking at it using an individual's chronotype.
This approach underscores the complexity of obesity and emphasizes that we need more studies that examine this problem from new and creative angles. Obesity is not an issue of "eat less, move more," and studies like this continue to unpack its complexity.