For as long as I can remember, I’ve been schooled on the importance of eating a substantial breakfast. But millions of people routinely skip breakfast and it doesn’t seem to hurt them. In fact, we’re now hearing that periods of fasting are beneficial. So why is breakfast supposed to be such a great thing? —Rob Lewis
Funny you should mention this just now, Rob. We’re fast approaching the culmination of a five-year cycle wherein the Departments of Agriculture and Health and Human Services draw on the current scientific literature and come up with recommendations about how people should be eating. Last time around, in 2010, the Dietary Guidelines for Americans suggested that skipping breakfast could lead to obesity, leaning on evidence like a 2007 study in which men who ate a morning meal were found less likely to gain weight. (If you’re thinking there’s a lot more to good health than skinniness: don’t worry, we’ll get there.) “Eat a nutrient-dense breakfast,” goes this terse recommendation, noting that breakfast-skipping has been “associated with” weight gain.
Hang on, you say—“associated with”? That’s even slipperier than “correlated with,” right? Buddy, you’re not alone. A 2013 paper on the “proposed effect of breakfast on obesity,” or PEBO, undertook a meta-analysis of the available research. The paper’s title is “Belief Beyond the Evidence,” if that gives you any idea of where and how strongly its authors stand on the subject; they write, “The observational literature on the PEBO has gratuitously established the association, but not the causal relation, between skipping breakfast and obesity.” They also spend a little time tracking the PEBO on its journey from the academy to the popular consciousness, finding it parroted everywhere from respected sources like the Mayo Clinic to, um, less-respected sources like Dr. Oz. Their objections are several, but revolve (as suggested in the above quote) around the observational nature of the work they analyze—observational studies being, as their name indicates, far less rigorous than those based on that scientific gold standard, the randomized controlled trial.
Helpfully, a couple teams of researchers have pitched in with RCTs over the last several years. One such study, conducted at a New York hospital, divided obese patients into three groups; over four weeks, one got high-fiber oatmeal for breakfast, one got no-fiber Frosted Flakes, and a control cohort skipped breakfast altogether. Turned out that the no-breakfast crew lost a little weight compared to the other two. A study published in 2014 in the American Journal of Clinical Nutrition arrived at a similar conclusion.
(How this will affect the 2015 Dietary Guidelines is impossible to know, but the advisory-committee report that comes out ahead of the guidelines, which was published in February, keeps mum on the association between breakfast-skipping and obesity. “I just don’t think it surfaced as a priority question,” the committee chair told the Washington Post. The report notes only that breakfast tends to have a “higher overall dietary quality” compared with other meals because of the greater nutrient density of breakfast foods. Presumably they’re not eating Frosted Flakes.)
Those New York researchers did find higher cholesterol levels in the breakfast-skippers, which suggests to me that “Does it or doesn’t it make you fat?” is perhaps not the apposite question here, though in recent years it’s one that’s preoccupied nutritionists and, as those federal guidelines indicate, policymakers. There’s plenty of other health benefits breakfast has to recommend to it: regular consumption of the meal has been linked to lower risks of heart disease and type 2 diabetes, for instance.
Of course, in my tender youth, it wasn’t like my mother was telling me to eat a good breakfast so I’d have better cholesterol in middle age. Rather, kids get some hazy bromide about “feeding your brain.” So what about that? Well, a 2013 lit review in Frontiers in Human Neuroscience found that the available information “may indicate that children who eat breakfast are more able to concentrate, pay attention and are more alert at school.” On the other hand, it also noted that much of the research (again) lacked “scientific rigor”: beyond the subjective nature of evaluating kids’ classroom behavior, you’ve got major confounding factors like socioeconomic status, which tends to correlate independently with both academic performance and breakfast-eating.
But what if, as you suggest, we rebrand breakfast-skipping as fasting, in accordance with new diet trends? Eh—the jury’s still out. The case has been made that skipping breakfast—i.e., de facto fasting, assuming you haven’t eaten all night—increases the stress on your body such that it can result in insulin sensitivity, then diabetes, then high blood pressure, etc. The case has also been made (via work with mice, at least) that skipping a meal increases stress on the body such that cells build important defenses, and the skippers end up leaner and healthier. Maybe by 2020 the feds will have something to offer this discussion; maybe by 2025 it’ll even be right. —Cecil Adams