Is breakfast the most important meal of the day? A recent meta-analysis suggests that this might be one of the myths in nutrition. The article published in the British Medical Journal (BMJ) argues that the studies used to indicate that breakfast is the most important meal of the day may be biased. The case for breakfast was built on the fact that the idea that spreading out meals throughout the day and eating little and often (grazing rather than gorging) to avoid “stress” on the body from having to digest large meals. Studies also showed that obese and diabetic people skipped meals more often than thin people. From this it was deducted that thus having breakfast was essential for maintaining a healthy body weight.
Before I discuss the study and the evidence, it is important to pause and put the study into context. The study in the BMJ was about breakfast and weight change and/or energy intake; or in other words breakfast and maintaining a healthy weight. There are of course many other reasons why people eat breakfast. Weight loss is not the only reason for having a breakfast in the morning. For example, an athlete might eat breakfast for performance or continued recovery from the training the day before. The article in the BMJ is a summary of studies about preventing weight gain or effects on energy intake later in the day, not about performance, recovery or any other aspect. Without any doubt this context will be forgotten in many views that will be published in the aftermath of this publication in BMJ and will finds its way to the general population through popular magazines, social media and other channels. The message will be “breakfast is not important” or perhaps “it is better to skip breakfast”… My answer to the question to the question “Is breakfast the most important meal of the day?” is still “It depends”. It depends on the goal of the breakfast. For a cyclist, who has an important one-day bike race, breakfast may indeed be the most important meal of the day. It is the only meal where he or she can stock up on carbohydrate and benefit during the race. Starting the race without the breakfast would have consequences for performance. The meals after the race are too late to affect performance even though they are of course important for recovery.
If the goal is weight loss, the review in BMJ shows that having a breakfast is not essential. It may even be better to have no breakfast. Studies have shown that if breakfast is skipped, this may mean that intake is somewhat compensated later in the day and physical activity may be reduced later in the day but not enough to make up the lower energy intake at breakfast.
The BMJ study
Of 13 included trials, seven examined the effect of eating breakfast on weight change, and 10 examined the effect on energy intake. Meta-analysis of the results found a small difference in weight favouring participants who skipped breakfast (mean difference 0.44 kg, 95% confidence interval 0.07 to 0.82). The authors also note that there is quite a bit of inconsistency across trial results. Participants who had a breakfast had a higher total daily energy intake than those assigned to skip breakfast (mean difference 260 kcal/day). The authors also state that all of the included trials had only short term follow-ups (a few weeks for weight changes and a couple of weeks for energy intake) and that the quality of the included studies was mostly low. The authors thus state that the findings should be interpreted with caution. So the authors are careful kin their conclusions and discuss limitations, but these will not be picked up and discussed by the media outlets that will now report that “breakfast is not important”…
What is a little puzzling to me is the conclusion of the BMJ study: The authors conclude: this study suggests that the addition of breakfast might not be a good strategy for weight loss, regardless of established breakfast habit. This suggests that people are having breakfast with the purpose of losing weight. Personally, I am not aware of anyone who eats breakfast with the goal to lose weight. I know of people who skip breakfast to lose weight… and maybe those people are indeed doing something that might work for them. I am also aware of the advice to not skip breakfast for weight loss. But this is not the same as eating breakfast to lose weight, but maybe these are semantics. My opinion: Whether breakfast is the most important meal of the day depends on the goal. In many cases there is little or no evidence to suggest that there is a problem with skipping breakfast, but especially for athletes and when performance is important, breakfast is a very important meal. On certain days when training low is in the athlete’s training plan, training without a breakfast may be appropriate. It depends.
BMJ 2019; 364 doi: https://doi.org/10.1136/bmj.l42 (Published 30 January 2019)