These studies show that people who eat breakfast are more likely to be healthier, but they can not prove that the breakfast itself caused it.
Chances are that breakfast eaters have other healthy lifestyle habits that can explain this.
For example, people who eat breakfast also tend to eat a healthier diet, with more fiber and micronutrients (5, 6).
On the other hand, people who skip breakfast tend to smoke more, drink more alcohol and exercise less (7).
Perhaps these are the reasons that breakfast eaters are healthier, on average. It may not have anything to do with the breakfast itself.
In fact, higher quality studies called randomized controlled trials suggest that it doesn’t really matter whether you eat or skip breakfast.
Bottom Line: Breakfast eaters tend to be healthier and leaner than breakfast skippers. This may be due to the fact that breakfast eaters have other healthy lifestyle habits.
Eating Breakfast Does Not Boost Your Metabolism
Some people claim that eating breakfast “kick-starts” the metabolism, but this is a myth.
These people are referring to the thermic effect of food, which is the increase in calories burned that occurs after you eat.
However, what matters for metabolism is the total amount of food consumed throughout the day. It makes no difference at which times, or how often, you eat.
Studies show that there is no difference in calories burned over 24 hours between people who eat or skip breakfast (8).
Bottom Line: Whether you eat or skip breakfast has no effect on the amount of calories you burn throughout the day. This is a myth.
Skipping Breakfast Does Not Cause Weight Gain
As mentioned above, people who skip breakfast tend to weigh more than people who eat breakfast.
This may seem paradoxical, because how can not eating make you gain more weight?
Well, some claim that skipping breakfast causes you to become very hungry so that you overeat later in the day.
This seems to make sense, but isn’t supported by the evidence.
It is true that skipping breakfast causes people to be more hungry and eat more at lunch, but this is not enough to overcompensate for the breakfast that was skipped.
In fact, some studies have even shown that skipping breakfast mayreduce overall calorie intake by up to 400 calories per day (9, 10, 11).
This seems logical, because you are effectively removing an entire meal from your diet each day.
Interestingly, the eat/skip breakfast dilemma was recently tested in a high-quality randomized controlled trial.
This was a 4-month long study that compared recommendations to eat or skip breakfast in 309 overweight/obese men and women (12).
After 4 months, there was no difference in weight between groups. It simply didn’t matter whether people ate or skipped breakfast.
These results are supported by other studies on the effects of breakfast habits on weight loss. Skipping breakfast had no visible effects (5, 12, 13).
Bottom Line: Higher-quality studies show that it makes no difference whether people eat or skip breakfast. Skipping breakfast makes you eat more at lunch, but not enough to compensate for the breakfast you skipped.
Skipping Breakfast May Even Have Some Health Benefits