Burnt: breakfast theory --- Breakfast is a Dangerous Meal.

Oliver Moody, TT, London, Dec. 24: Breakfast like a king, lunch like a prince and dine like a pauper - if you want to overeat and put yourself at increased risk of developing diabetes, according to a new book.

A British biochemist argues that people should fast until lunch if they want to stay healthy and that the case for breakfast has been trumped up by flawed studies and the insidious influence of the food industry.

Terence Kealey, a former clinical lecturer at Cambridge University who was also vice-chancellor of Buckingham University between 2001 and 2014, sets out the case against porridge and Danish pastries in his book, Breakfast is a Dangerous Meal.

If people insist on eating in the morning, a bowl of fruit or even a modest fry-up is, he says, preferable to starchy toast or cereal.

The carbohydrate-rich breakfast, Kealey says, leads to a mid-morning jump in levels of the sugar-curbing hormone insulin, and doing this often enough is a recipe for type 2 diabetes. And he ought to know.

Kealey found out that he had the condition in 2010. Using a finger-prick testing device called a glucometer to measure his blood sugar, he discovered that the levels were "dismayingly high first thing in the morning, but - even worse - they would rise much further, indeed hazardously, if I ate breakfast".

The prevailing wisdom is that the four out of five people who eat breakfast are doing the right thing. As with many nostrums in nutrition science, however, the reality is that the evidence is a contradictory mess.

Most of the statistics that are touted around about eating breakfast are based on observational studies, where researchers ask people what they eat and then measure certain things about them.

The problem, according to Kealey, is that this makes it very hard to tell whether the participants are healthy because they eat breakfast or because they do other things that healthy people do. In the few cases where scientists have intervened, the results have been very different.

A 2014 study from Bath University showed that people who were given a 700-calorie breakfast ate 539 calories more over the day than those who missed the meal. Even though the breakfast-skippers ate more at lunchtime it was nothing like enough to make up the difference between the two groups.

There are some caveats. Some experiments have found that eating breakfast makes people fidget and move around more during the day, meaning that they end up burning off more energy.

Different people also have different body clocks and genetic factors that could render a one-size-fits-all approach to breakfast unworkable. Last year, Israeli scientists found a nine-fold difference in the way people's blood sugar levels changed in response to eating bread.

Those who cut back heavily on calories in an attempt to lose weight also release chemicals called free fatty acids when they are fasting. These can lead to a perilous rise in blood sugar levels after lunch if the dieters skip breakfast.