You may have grown up constantly hearing that breakfast is the most important meal of the day. It was claimed to kick-start your metabolism and reduce over-eating later in the day, ultimately helping maintain a healthy weight. Recent research, however, has raised doubts over the veracity of this commonly held belief, and a new meta-analysis has concluded there is no good evidence to suggest eating breakfast promotes weight loss or improves metabolic rates later in the day.

The meta-study gathered data from 13 separate randomized control trials, all conducted to compare the effects of eating breakfast and skipping breakfast in adults. The results were pretty clear with the breakfast groups eating, on average, 260 calories more per day than those that skipped breakfast. Those that skipped breakfast also weighed an average of one pound (0.44 kg) less than their breakfast eating counterparts.

Of the studies included in the review that examined metabolic rates and hormone levels associated with appetite regulation, the data revealed no significant difference between breakfast consumers and breakfast skippers. Two studies examining changes in diet-induced thermogenesis, the metabolic process in which your body converts calories to heat, also found virtually no differences between the two groups.

All of this evidence adds up to a reasonably confident conclusion that breakfast consumption does not promote weight loss or play a major role in altering energy expenditure across the day. In fact, the researchers suggest that eating breakfast may, in some cases, have the opposite effect and hinder weight loss plans.

"Although eating breakfast regularly could have other important effects, such as improved concentration and attentiveness levels in childhood, caution is needed when recommending breakfast for weight loss in adults, as it could have the opposite effect," the researchers conclude in the published article.

But why then has such as strong anecdotal history built up around the idea of breakfast being so beneficial and important? Almost every major governmental health body around the world recommends breakfast as important and advises people to avoid skipping it.

Tim Spector, from King's College London, examines this very question in an opinion piece published in coordination with the new research. Spector suggests the idea that breakfast is important may stem from the classic causation/correlation problem that haunts the vast majority of observational research. While epidemiological studies may often show that, in general populations, people who skip breakfast tend to be more overweight and eat more later in the day, this does not mean skipping breakfast actively causes those subsequent effects.

"People who skipped breakfast were more likely on average to be poorer, less educated, less healthy, and to have a generally poorer diet," Spector writes. "Overweight people were more likely to try and diet, and after a binge were more likely to feel guilty and skip a meal."

Some research is affirming that large caloric intakes late in the evening can be unhealthy. So, certainly, skipping breakfast and having a big dinner late at night is not an ideal strategy, but it is becoming increasingly clear that breakfast, in and of itself, is not as important as we previously suspected. Spector does note that every individual's biological make up is different, so there is no "one size fits all" piece of advice regarding breakfast.

"Around a third of people in developed countries regularly skip breakfast, whereas many others (including myself) enjoy it," Spector writes. "This does not mean that all overweight people would benefit from skipping breakfast. Some people are programmed to prefer eating food earlier in the day and others later, which might suit our unique personal metabolism."

The new study was published in the journal BMJ.

Source: The BMJ via SciMex