Shattering The Myth of The Most Important Meal of The Day

Bigger burn

The results also quash the idea that if you skip breakfast you’ll be ravenous later on. In the lab the team took blood samples to measure ghrelin, a hunger hormone, and found something unexpected. Levels of the hormone were much the same at lunchtime, irrespective of whether breakfast was on the menu (see “Hunger hormone”). “That might partly explain why those who fasted didn’t overeat that much,” Betts says. “But the bit that was surprising was that after lunch, ghrelin levels dropped in those who had fasted but stayed high in those who had had breakfast.”

Despite some gentle cajoling, Betts refuses to coin the “Augustus Gloop” effect, in which the more somebody is used to eating, the more they might want to eat later in the day. There’s not yet enough evidence, he says. He is more confident about the team’s finding that skipping breakfast did not affect fat levels or weight gain, which is corroborated by a much larger 2014 randomised trial. This all suggests that a doctor’s advice to start the day with breakfast might be misguided.

So does breakfast have any benefits at all?

It turned out that the breakfast eaters had better control over glucose levels in the afternoon, an advantage that Betts wants to probe further, especially since we know that this is what goes wrong in people with type 2 diabetes.

Other work backs up this idea. One study showed that children who ate breakfast every day, especially high-fibre cereal, were at lower risk of developing type 2 diabetes later on in life. “Our work and others’ certainly show an association between not eating breakfast and an increased risk of later disease such as type 2 diabetes,” says Peter Whincup at St George’s, University of London, who led the research.

Even so, Whincup warns against over-interpreting data from these kinds of studies because they are observational and come with the usual caveats. Plus his research was based on asking children to remember what they had eaten, which is prone to errors.

Perhaps the biggest boon of breakfast is that those who indulge, while tending to eat more during the day, manage to burn off those calories later on — an effect that we didn’t know about before. Betts’s team used heart rate monitors and accelerometers to measure movement, giving them the edge over past studies based on questionnaires alone. These would have missed lower-intensity activities such as unconscious movement or fidgeting, otherwise known as “non-exercise activity thermogenesis”, or NEAT. And even light activity can make a big difference. Calorie expenditure from low-intensity activities was significantly higher in breakfast eaters than in the fasters. They also burned on average several hundred more calories during the morning than their fasting counterparts (see “Bigger breakfast burn”). Those who fasted just moved around less without thinking about it.

“It makes sense from an evolutionary perspective,” Betts says. “Our bodies are strongly evolved to defend against weight loss, so if you’ve eaten fewer calories your body might compensate by doing less.”

This adds another level of sophistication to our breakfast decision-making. We should chew over the idea every morning rather than unthinkingly reaching for the porridge — there might indeed be good reason to skip it, especially if you’re stuck in a plane or conference all day without much chance to move.

Breakfast brain boost

But even if breakfast’s reputation as the most important meal of the day is no longer secure, we shouldn’t lay down our knives and forks just yet. “We’ll need to find out about different types of breakfast foods: perhaps those rich in fats, carbohydrates or protein,” says Betts. “And we didn’t include caffeine in our tests, but maybe it could encourage greater physical activity even if you skip breakfast?”

There is also the question of whether missing breakfast takes a mental toll (watch our video above). Betts didn’t measure mood or cognition, the effects most often mentioned — or moaned about — by colleagues who haven’t eaten breakfast.

That question is hard to answer. Children who miss breakfast do not perform as well at school as those who eat it regularly, but that could be because the provision of breakfast is a marker of socioeconomic circumstance or stability at home.

In the absence of fake food, there’s no placebo for the first meal of the day, which makes fair studies tricky. “If somebody turns up to a study and doesn’t receive breakfast they might feel annoyed and expect to have a slump in energy,” says Peter Rogers, at the University of Bristol, UK. “There’s actually a suggestion that eating too much for breakfast could adversely affect you and make you sluggish — think about how you feel after Christmas lunch.”

So next time someone preaches about the benefits of breakfast, you’re perfectly entitled to shrug and walk away. “Most of us could do with eating less,” Rogers says. “Given that it’s probably the easiest meal to skip, maybe skipping breakfast occasionally could be that opportunity.”