A LOT of health advice is hard to swallow. But it can be made more palatable if it tastes like crispy bacon and lightly poached eggs, a buttery croissant or a steaming bowl of porridge鈥 This is perhaps why the idea that breakfast is the most important meal of the day has stuck to our collective subconscious like an egg to an unoiled pan.
The health claims for breakfast are innumerable. It can boost your metabolism, leave you eating more healthily for the rest of the day, plus you鈥檒l have more energy and be less likely to put on weight, which is good news for avoiding heart disease and diabetes.
鈥淭he problem is that these benefits, although logical sounding, are largely assumptions based on observational studies and had never actually been tested,鈥 says , who studies nutrition and metabolism at the University of Bath, UK. 鈥淚 was amazed when I started looking for evidence 鈥 I thought there would be a lot,鈥 he says. What was out there, though, didn鈥檛 stand up to scrutiny. So he decided to find out for himself.
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The concept of a healthy breakfast was probably first introduced at the turn of the last century by John Harvey Kellogg to promote his new breakfast cereal (see 鈥The original 鈥榟ealth food鈥鈥). Despite these dubious beginnings, a body of research has since been published to support the idea. Studies show, for instance, that both and children who skip breakfast could end up at increased risk of type 2 diabetes. Other work found that eating breakfast cereals leads to a healthy BMI in adolescent girls and that teens who skip the meal are . So surely eating breakfast amounts to a simple and important public health message?
Not quite. There is one big problem 鈥 these and similar findings are based on observational studies, in which investigators watch people going about their normal life, without control groups. This means that other elements of the person鈥檚 lifestyle 鈥 such as regular exercise or getting a good night鈥檚 sleep 鈥 could truly be driving the health effects. So are people healthy because they eat breakfast, or do they eat breakfast because they are healthy?
鈥淧eople who eat breakfast burn off the extra calories without even trying鈥
It鈥檚 not a trivial matter. Given that so many countries are in the midst of an obesity epidemic, Betts thinks questioning the value of breakfast should ensure advice dished out by doctors is based on solid evidence. 鈥淎s soon as doctors find out that an overweight patient skips breakfast they鈥檒l often tell them to make sure they eat it every day,鈥 he says. 鈥淏ut should we not know more about the effects? We try not to give other health advice without evidence, so why are we more lax with breakfast?鈥
To separate the (Shredded) wheat from the chaff and determine what, if any, causal effect breakfast can have on health, Betts and his team decided to conduct a randomised trial. One group ate breakfast, while the other fasted and drank just water until lunch. Those who ate breakfast had to chow down on a whopping 700 calories or more before 11 am. The team then recorded a range of measurements throughout the day 鈥 either by monitoring participants in the lab or by having them keep their own records.
[youtube]https://www.youtube.com/watch?v=B6ud-iCGkbU[/youtube]
First, they looked at daily total consumption. Does breakfast really make people less likely to overeat at lunch or dive into the biscuit tin?
Contrary to accepted wisdom, skipping breakfast had little effect 鈥 those who fasted all morning ate more at lunch, but not enough to make up the 700 calorie deficit, which meant that up eating a fair bit more over the day (see 鈥淏reakfast binge鈥). And eating breakfast didn鈥檛 give people a much-touted metabolic boost either.
Bigger burn
The results also quash the idea that if you skip breakfast you鈥檒l 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 鈥淗unger hormone鈥). 鈥淭hat might partly explain why those who fasted didn鈥檛 overeat that much,鈥 Betts says. 鈥淏ut 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.鈥
Despite some gentle cajoling, Betts refuses to coin the 鈥淎ugustus Gloop鈥 effect, in which the more somebody is used to eating, the more they might want to eat later in the day. There鈥檚 not yet enough evidence, he says. He is more confident about the team鈥檚 finding that skipping breakfast did not affect fat levels or weight gain, which is . This all suggests that a doctor鈥檚 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 . 鈥淥ur work and others鈥 certainly show an association between not eating breakfast and an increased risk of later disease such as type 2 diabetes,鈥 says at St George鈥檚, University of London, who led the research.
鈥淪kipping breakfast does not affect fat levels or weight gain鈥
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 鈥 an effect that we didn鈥檛 know about before. Betts鈥檚 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 鈥渘on-exercise activity thermogenesis鈥, 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 鈥淏igger breakfast burn鈥). Those who fasted just moved around less without thinking about it.
鈥淚t makes sense from an evolutionary perspective,鈥 Betts says. 鈥淥ur bodies are strongly evolved to defend against weight loss, so if you鈥檝e eaten fewer calories your body might compensate by doing less.鈥
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 鈥 there might indeed be good reason to skip it, especially if you鈥檙e stuck in a plane or conference all day without much chance to move.
Breakfast brain boost
But even if breakfast鈥檚 reputation as the most important meal of the day is no longer secure, we shouldn鈥檛 lay down our knives and forks just yet. 鈥淲e鈥檒l need to find out about different types of breakfast foods: perhaps those rich in fats, carbohydrates or protein,鈥 says Betts. 鈥淎nd we didn鈥檛 include caffeine in our tests, but maybe it could encourage greater physical activity even if you skip breakfast?鈥
There is also the question of whether missing breakfast takes a mental toll (watch our video above). Betts didn鈥檛 measure mood or cognition, the effects most often mentioned 鈥 or moaned about 鈥 by colleagues who haven鈥檛 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鈥檚 no placebo for the first meal of the day, which makes fair studies tricky. 鈥淚f somebody turns up to a study and doesn鈥檛 receive breakfast they might feel annoyed and expect to have a slump in energy,鈥 says , at the University of Bristol, UK. 鈥淭here鈥檚 actually a suggestion that eating too much for breakfast could adversely affect you and make you sluggish 鈥 think about how you feel after Christmas lunch.鈥
So next time someone preaches about the benefits of breakfast, you鈥檙e perfectly entitled to shrug and walk away. 鈥淢ost of us could do with eating less,鈥 Rogers says. 鈥淕iven that it鈥檚 probably the easiest meal to skip, maybe skipping breakfast occasionally could be that opportunity.鈥
The original 鈥榟ealth food鈥
Breakfast wasn鈥檛 always about a healthy start, you鈥檇 just 鈥渂reak the fast鈥 and replenish energy supplies after a long night鈥檚 sleep. 鈥淗istorically, if you had a hard day ahead of you doing manual labour on the farm, it made sense to refuel with a good breakfast. The idea of health didn鈥檛 really come into it,鈥 says , professor of nutrition and behaviour at the University of Leeds, UK.
Then came the industrial revolution. Our days became less physical and the need for refuelling less obvious. 鈥淚t was around the turn of the last century when Dr Kellogg popped up with his cereal, which really revolutionised the idea of breakfast as being healthy,鈥 says , a social anthropologist at University College London.
Legend has it that John Harvey Kellogg, a Seventh-Day Adventist, invented his cornflakes because he thought that eating pure, wholesome food would stop people masturbating. That apart, as a doctor he also believed that the common health concerns of the day 鈥 digestion and regularity 鈥 could be improved by consuming the fibre in his cornflakes, says O鈥機onnor. 鈥淜ellogg managed to take these free-floating health anxieties and embody them in a product,鈥 she says.
Both the product and the concept were received very well. 鈥淧eople hadn鈥檛 really had health food marketed to them before,鈥 says O鈥機onnor. For women who鈥檇 traditionally cooked a large breakfast for their family it was a godsend 鈥 the fact that it was healthier for their families took the guilt away from buying breakfast in a box. 鈥淚t was such a successful marketing vehicle that others piggy-backed on to it.鈥
Other staples of our breakfast routine, including orange juice and coffee, followed. The popularity of bacon for breakfast was allegedly the brainchild of Edward Bernays, the self-styled grandfather of public relations. In the 1920s, he was commissioned by the US pork industry to boost bacon sales. Bernays surveyed medical doctors and asked them one question: is a hearty breakfast preferable? The resounding answer was yes, presumably, says Dye, as a relic of the ideas of breakfast and refuelling from bygone agricultural days. Bernays used this fact in marketing campaigns and the popularity of bacon and eggs went through the roof.
鈥淟et鈥檚 not trash the benefits of breakfast all together,鈥 says O鈥機onnor, 鈥渂ut it鈥檚 safe to say that the idea that it is healthy in its own right was laid on a plate for us by marketing companies. And, by and large, we鈥檝e gobbled it up.鈥
This article appeared in print under the headline 鈥淭he great breakfast myth鈥
