The positive benefits of breakfast in weight loss has been the long-held beliefs and widespread medical recommendations of many. Despite this we have reasons to think that breakfast does not appear to have an important role in weight loss after all, with a new meta-analysis showing no evidence that eating breakfast reduces daily caloric intake and weight gain is no worse among those who skip the meal.
“While breakfast has been advocated as the most important meal of the day in the media since 1917, there is a paucity of evidence to support breakfast consumption as a strategy to achieve weight loss, including in adults with overweight or obesity,” the authors conclude.
“This systematic review of randomized controlled trials examining weight change in adults consuming or skipping breakfast found no evidence to support the notion that breakfast consumption promotes weight loss or that skipping breakfast leads to weight gain,” they add.
In their meta-analysis, Katherine Sievert and colleagues with the School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia, evaluated data from 13 randomized controlled trials, including seven that examined the effect of eating breakfast in weight loss (n = 486) and 10 that examined the effect on energy intake (n = 930).
Although there was some inconsistency between studies, overall there was a very small difference in weight favoring participants who skipped breakfast (mean difference, 0.44 kg).
Meanwhile, studies in which participants were assigned to eat breakfast showed they had a higher total daily energy intake than those allocated to skip breakfast (mean difference, 259.79 kcal/day), contrary to theories that not consuming breakfast leads to over-compensation later in the day.
“There was no evidence that skipping breakfast was associated with an increased total daily caloric intake,” say Sievert and colleagues.
In an accompanying editorial, Tim Spector, MD, professor of genetic epidemiology at King‘s College, London, UK, notes that the “disadvantages of skipping breakfast have now been debunked by several randomized trials,” which are examined in the current meta-analysis.
The conclusions were the same as in recent, largely ignored qualitative reviews, he adds, “namely, that no evidence supports the claim that skipping breakfast makes you gain weight or adversely reduces your resting metabolic rate.”
Importantly, the overall data underscore that metabolism may simply be more of an individualized concept than has previously been realized, and a “one size fits all” approach may be futile, he says.
Benefits of Breakfast in Weight Loss: Low Quality Studies Included, Interpret Findings With Caution
In their article, Sievert and colleagues explain that much of the previous research linking consumption of breakfast with healthy weight is based on observational studies, but those studies may have important caveats in terms of participants’ lifestyle.
“There are data to suggest that these findings on regular breakfast consumption in observational studies are reflective of a wider healthy lifestyle, in that individuals who are more health conscious and of higher socioeconomic status are more likely to eat breakfast as part of making healthy food choices,” they explain.
The studies in the current analysis nevertheless had a variety of caveats of their own, including the fact that many either had a high or unclear risk of bias and follow-up periods were generally short, with a mean of 7 weeks for weight and 2 weeks for energy intake.
“As the quality of the included studies was mostly low, the findings should be interpreted with caution,” the authors underscore.
Furthermore, with the analysis focusing on issues of weight management, conclusions cannot be made about the numerous other asserted health benefits of breakfast.
“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.”
Could the Gut Microbiome Play a Role?
In his editorial, Spector goes on to explain that evidence is increasingly pointing to the potential benefits of fasting intervals in weight loss.
And there may be a connection between the gut microbiome and timing as well as type of meals, he added. “The community of 100 trillion gut microbes have a circadian rhythm and vary in composition and function in fasting and fed states,” he explains.
“Although this is a young discipline, some data suggest that microbial communities could benefit from short periods of fasting.”
He concludes: “While waiting for guidelines to change, no harm can be done in trying out your own personal experiments in skipping breakfast.”