There's a great article on the science of breakfast in New York Magazine this week that takes a thorough tour of the claims made about a regular morning meal (i.e., that it stokes your metabolism, cuts the risk of obesity and diabetes, and helps concentration). I wrote about this topic earlier this year, too.
The author didn't find convincing evidence that the very act of eating breakfast is necessary for every adult (for kids, it's another story—you won't find many people arguing they don't need to start the day with at least something in their stomachs). NYU nutrition professor and author Marion Nestle, who is not a breakfast eater, is quoted in the story. In an interview earlier this year, she explained more fully why she thinks people shouldn't feel compelled to eat in the morning if they aren't hungry. As to what we're supposed to choose if we do eat breakfast, the piece comes down on the side of unprocessed foods like oatmeal, whole grains, low-fat dairy, and the occasional egg.
A key point in the article is that research on diet and lifestyle is very tough to do, an issue I wrote about last summer. As NYM's Amanda Fortini puts it:
The real problem, from a researcher's point of view, is that breakfast consumption is a habit that tends to occur along with a constellation of other healthy behaviors—like exercising, not smoking, and maintaining a healthy diet—that may confound or influence the effect of breakfast on obesity. (Unhealthy behaviors, too, tend to stick together: Fewer than 5 percent of smokers eat breakfast daily.) In at least one study, when confounding variables were accounted for, the relationship between breakfast and body-mass index was not significant. The eating of breakfast was only an ancillary factor, one salubrious practice among several that contributed to slimness. Breakfasting and forgoing the gym will probably do little to reduce or control one's weight. In the Pediatrics study, for example, it seemed surprising that the breakfast eaters often had a higher daily caloric intake and yet also a lower BMI than their breakfast-skipping peers, but when I asked [breakfast researcher Mark A.] Pereira what explained this finding—had eating a morning meal somehow increased the subjects' metabolism?—he emphasized that the eaters were exercisers as well.
Keep that in mind when you're reading about studies and attempting to apply the findings to your own life; in many cases (except the obvious, like smoking), it's not so much one factor that's making a person healthier, but an entire lifestyle.