Breakfast is a Dangerous Meal: Why You Should Ditch Your Morning Meal For Health and Wellbeing. Terence Kealey

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       Myth No. 3: Breakfast is slimming

      Pundit after pundit asserts that breakfast produces satiety (from the Latin satis, enough). Breakfast, it is claimed, fills people’s stomachs and raises their blood sugar levels so they eat less at subsequent meals. Is this true?

      There are of course peer-reviewed scientific papers that make such assertions, and a man who has written many of them is Dr John de Castro, a Texas psychologist, who in 2004 wrote: ‘we found that when individual subjects ate a larger than mean proportion of their total intake in the morning, they ate significantly less over the entire day.’¹ Which apparently means that the more someone eats at breakfast, the less they eat during the rest of the day. De Castro attributed this to satiety. Here is his model:

      Eat breakfast → satiety → eat less at lunch → lose weight

      This is a powerful model, which at first sight seems to make sense. But most scientists find the exact opposite. In a recent study David Levitsky and Carly Pacanowski of Cornell University, New York, showed that when subjects were provided with light breakfasts (approx. 350 calories) their intake at lunch was completely unchanged: i.e. those 350 breakfast calories did not cause a compensatory fall in lunch calories, so on eating breakfast their daily intake went up by 350 calories. Moreover, when the subjects ate full breakfasts of around 624 calories, they reduced their lunch calories by only about 144 calories, causing a net increase of 480 calories a day.² No wonder Levitsky and Pacanowski concluded that ‘skipping breakfast may be an effective means to reduce energy intake.’ The Levitsky and Pacanowski model is, therefore:

      Skip breakfast → consume less food → reduce energy intake

      or vice versa

      Eat breakfast → consume more food → increase energy intake

      And what made Levitsky and Pacanowski’s study so significant is that they showed that ‘these data are consistent with published literature.’ That is to say there is widespread agreement that de Castro’s satiety hypothesis is wrong and that eating breakfast increases energy intake.

      Indeed, an overview of forty-seven of the most authoritative breakfast studies performed between 1952 and 2003 confirmed that around 20 per cent of children and adults skip breakfast, and that ‘breakfast eaters generally consumed more daily calories.’³ So, contrary to myth, eating breakfast piles on the calories. How then do we account for de Castro’s finding that ‘when individual subjects ate a larger than mean proportion of their total intake in the morning, they ate significantly less over the entire day’?

      Dramatically, Dr Volker Schusdziarra and his colleagues from the obesity clinic at the Technical University of Munich in Germany dismiss de Castro’s breakfast conclusions as a statistical illusion.⁴ On studying a cohort of subjects, Dr Schusdziarra found that, left to their own devices, people tend to eat fairly consistently in the mornings (i.e. breakfast is a relatively fixed-sized meal, because it is a habit) but people tend to eat inconsistently later in the day: on some days (for whatever reason – Aunt Flo’s birthday party, a celebratory restaurant meal) people will eat more at lunch and dinner, whereas on other days (for whatever reason – not feeling well, being rushed at work) people will eat less at lunch and dinner.

      Yet because the intake at breakfast is reasonably fixed, on the days that people ate large lunches and dinners, the proportion of their food intake from breakfast was small, while on the days they ate small lunches and dinners, the proportion of their food intake from breakfast was large. So it looks as if:

      small breakfasts → large overall food intake

      And

      large breakfasts → small overall food intake

      But these are illusions based on the greater variability of consumption at lunch and dinner, and the real model is:

      large intake at lunch and dinner → breakfasts correspondingly small, relatively

      And

      small intake at lunch and dinner → breakfasts correspondingly large, relatively

      Schusdziarra was rightly respectful of de Castro’s data; it was only his interpretation he challenged. And this, as will be seen, is the theme of this book: the accumulated breakfast data of literally hundreds of scientists is almost always sound (it’s amazing how much breakfast research has been performed), but the findings have been systematically misinterpreted.