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The Story of Breakfast, Part 2

ByTerence Kealey, MD, Ph.D.February 7, 2020

One great problem with breakfast is that it drives up our intake of calories. The myth is that breakfast is filling, so we’ll eat less at lunchtime. But this myth (the so-called satiety myth, after satis, the Latin for “enough”) has been exposed repeatedly. Careful experiments show that a light breakfast of, say, 350 calories, will leave unchanged the amount people eat at lunchtime; while a heavy breakfast of, say, 625 calories, will reduce lunchtime consumption by only about 150 calories. Breakfast piles on the calories.

And breakfast not only fails to induce satiety; it can even do the opposite and stimulate hunger. Breakfast induces peaks in blood glucose levels, which are followed by troughs, and those troughs will often generate additional hunger. Thus does breakfast pile on even more calories.

Another great problem is that people who eat breakfast tend to be slim. Yup, you read that right. People who eat breakfast tend to be slim, which has been the mainstay of the cereal, bacon, and egg companies, who shout it from the rooftops: People who eat breakfast tend to be slim. Therefore we should eat breakfast. It’s obvious, isn’t it? But …

  • People who eat breakfast tend to smoke less than breakfast skippers.
  • People who eat breakfast tend to exercise more than breakfast skippers.
  • People who eat breakfast tend to eat less, overall, than breakfast skippers.
  • People who eat breakfast tend to eat less fast food than breakfast skippers.
  • People who eat breakfast tend to have received more years in education than have breakfast skippers.
  • People who eat breakfast tend to watch less television than breakfast skippers.
  • People who eat breakfast tend to eat less meat than breakfast skippers.
  • People who eat breakfast tend to drink fewer sugary drinks than breakfast skippers.
  • People who eat breakfast tend to drink less alcohol than breakfast skippers.
  • People who eat breakfast tend to have more friends than breakfast skippers.
  • People who eat breakfast tend to eat more fiber than breakfast skippers.

So if the cereal, bacon, and food companies are to be believed, breakfast will reduce people’s smoking, it will cause them to exercise more, it will cause them to eat and drink less, it will encourage them to extend their education, it will wean them off television and meat and fast food and sugary drinks but onto fiber; and it will widen their circle of friends. A miracle meal! Quick, pour out those corn flakes and waffles and syrup and muffins and eggs and bacon! They’re good for you! They’ll raise your social class!

Social class? Well, of course, what we’re seeing is only an association. The more privileged socioeconomic groups tend to eat breakfast because they tend to lead ordered lives, and they tend to do what they’re told, so they tend to eat breakfast — in moderation — but they also tend to eat their other meals in moderation, and they tend to eschew fast food and cigarettes and alcohol and television and excessive meat and sugary drinks, but they will tend to exercise and eat fiber and go to school and maintain their social networks. Less privileged social groups, however, tend to lead less ordered lives, and they tend not to like being told what to do and they’ll tend to do the opposite of all of the above.

What is particularly devilish about the cascade of scientific papers that fills the journals chronicling the so-called benefits of breakfast is that the authors are always very careful to write they’re chronicling only an association between breakfast-eating and slimness or exam-passing or high income or whichever desirable attribute is the focus of any particular paper, yet they are also very careful to imply — by the way they write their papers — that they’re chronicling cause and effect. And even though these papers are almost invariably funded by the cereal, egg, or bacon companies, the accompanying articles in the newspapers will overlook any reference to association and will invariably present the data as cause and effect. Breakfast is good for you. Period.

I suspect the journalists, who will have been briefed by the companies’ PR departments, will know no better (though, for science and nutrition journalists, they’re generally amazingly uncritical of the way nutrition science is often funded and presented; it’s almost as if they believe scientific papers are always honest), but I am much more skeptical about the company-funded scientists themselves. I suspect many of them know exactly what they’re doing. Certainly, I can’t now read a scientific paper on breakfast without asking myself how the lying bastards are lying to me.

So, where does that leave breakfast today? The conclusions are fairly simple. If you are one of those lucky people who is not hungry in the morning, then don’t eat breakfast! One of the greatest of nutritional crime scenes is the sight of people who are not hungry forcing themselves to eat breakfast out of a misplaced sense of dietary duty. Don’t! Equally, if your children don’t want to eat breakfast, let them be (as long as they can get a mid-morning snack if they need one.)

On the other hand, if you like breakfast — and if you’re fit and slim and active — then feel free to eat what you like in the mornings. The fit and slim and active are the biochemically privileged members of society, for their bodies will consume those matutinal calories and glucose molecules without much difficulty (they’d still do better to go low-carb, though).

Everyone else, though, should adopt the simple rule of not a calorie before noon. Overweight and obesity are the great plagues of today, and time-restricted eating (i.e., eating only lunch and dinner within an eight-hour window) is the easiest way of achieving and maintaining low weight.

What, though, if you simply have to eat in the morning? Well, if you absolutely must, then do so — but don’t consume any carbohydrates! A breakfast of eggs, followed by berries (strawberries, blackberries, and blueberries are surprisingly low in sugar) and cream will be safe (but not yogurt — there’s sugar in yogurt).

And for diabetics? For Type 1s, the rule of no carbohydrates before noon is essential, for only after noon, after the cortisol peak has exhausted itself, will their bodies respond maximally to insulin. And the less insulin they need, the healthier they are likely to be. A warning, though: Type 1s should not skip breakfast or adopt low-carb generally without anticipating hypos; they’ll have to cut their insulin doses.

For Type 2s, who are generally overweight, breakfast is a particular menace, and they should avoid all calories before noon, because time-restricted eating is particularly important for them. But a low-carbohydrate, breakfast-skipping lifestyle can certainly work and work wonders: In my case, nearly a decade after my diagnosis, my HbA1c levels have never returned to the diabetic range, and though they’re reluctant to enter the normal range, and though my only treatment is 1 gram of metformin twice a day, they’ve remained firmly within the prediabetic range, which is a range with which I’m happy. It’s when the HbA1c levels rise into the diabetic range that more aggressive therapies need to be considered.

To conclude, breakfast is the most dangerous meal of the day because it’s the one we eat at the height of the cortisol peak, yet it’s also the one that has the loudest cheerleaders from the food companies. We need an Odysseus to stuff our ears with wax, to block out their siren calls.

Additional Reading

Terence Kealey was born in London, where he also went to medical school (Bart’s Hospital Medical School, University of London; in the U.K., most medical students start at the age of 18.) But he soon realized he wanted to do research, so after his house year (internship) he went to Oxford to do his D.Phil. (Ph.D.) in metabolism, where his supervisor (advisor) was Philip Randle. After some years at Oxford, he moved to Cambridge, where he lectured for many years in clinical biochemistry. He then moved as vice chancellor (president) to the University of Buckingham, which is the only university in the U.K. not to be funded directly by the state. After many years there, he moved to the Cato Institute in Washington, D.C., and though he has recently returned to the U.K., he remains an adjunct scholar at Cato.

His research focused on the cell physiology of human skin (his group, for example, was the first to grow hair follicles, including human hair follicles, in vitro), but when, 10 years ago, he developed Type 2 diabetes, he resurrected his earlier training in biochemistry and medicine to show that the conventional clinical advice of the day for Type 2 diabetics was bizarre. In 2016 he published Breakfast Is a Dangerous Meal (4th Estate, London).