For people trying to lose weight, forgoing the first meal of the day is often treated as a mortal sin. “Skipping breakfast to lose weight makes you fatter – and far more likely to raid the vending machine,” the Daily Mail wrote last year. More reputable sources, such as the Mayo Clinic, echo that sentiment: “If you skip breakfast — whether you’re trying to save time or cut calories — you may want to reconsider, especially if you’re trying to control your weight,” the Mayo Clinic warns.
According to the New York Times, however, these well-intended bits of advice are largely based upon small studies that showed a correlation between breakfast and weight gain or loss, but do not prove that breakfast causes that shift.
In a new paper published in the American Journal of Clinical Nutrition titled “Belief Beyond the Evidence,” researchers use the breakfast weight loss example to illustrate that researchers, too, are prone to biases and human error. After performing a cumulative meta-analysis on around 50 breakfast and weight-related articles, the researchers blatantly concluded: “The belief in the proposed effect of breakfast on obesity exceeds the strength of scientific evidence. The scientific record is distorted by research lacking probative value and biased research reporting. Research lacking probative value is a suboptimal use of collective scientific resources.”
In other words, much as those researchers want to believe that breakfast helps people lose weight or keep it off, the evidence is far from conclusive. “In the real world, when people form an opinion, they tend to seek out evidence that supports it and discard anything that contradicts it, a phenomenon academics refer to as confirmation bias,” the Times writes. Scientific authors are no exception, and in this case they “were almost exclusively biased in favor of the idea that eating breakfast protects against weight gain.”
On the other hand, few studies that have had the proper long-term design, sample size and controls in place to actually make a determination about breakfast and its affect on weight have largely found that “missing breakfast has either little or no effect on weight gain, or that people who eat breakfast end up consuming more daily calories than those who skip it,” the Times concludes.
So yes, breakfast may have a reputation as being most important meal of the day, but whether that sausage and cheese-laden breakfast sandwich will make you skinny is an entirely different cup of coffee.
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