Our caveperson ancestors, sometimes cited as healthy eaters we should emulate, never sat down to lunch at noon every day. Why should we?
The answer is that eating at irregular times interrupts our circadian rhythms, which in turn upsets everything else. And best of all, there’s a new buzzword to describe it all: chrono-nutrition.
Two new meta-studies, from King’s College London, and published in the Proceedings of the Nutrition Society, took a look at existing literature on the subject. One aimed to tease out the relationship of irregular eating and obesity, the other at the effects of irregular mealtimes on our metabolic processes. And both found that eating regularly makes a huge difference to our health.
Nutrition is tied up with time in two ways. First, many of our bodies’ food-related processes are controlled by circadian rhythms, including appetite, digestion and the metabolism of fat, cholesterol, and glucose, says King’s College. Circadian rhythms are our bodies’ built-in clocks, and they govern many important functions. But they also—and this is the second aspect—can be affected by when we eat. Thus, eating irregular meals can disrupt the very system that controls our nutritional processes.
And this disruption can have serious consequences. Shift workers, says one of the studies, "have an increased risk of a number of diseases including cancer, cardiovascular disease and metabolic syndrome." Another problem is "social jet lag," where our body clocks don’t match our social clocks. This can lead to obesity.
So, the thinking goes, if disrupted circadian rhythms lead to disease, and if eating at irregular times disrupts those rhythms, then skipping meals is very bad for your health. The evidence from these meta-studies supports this theory.
Skipping meals not only upsets your finely tuned nutritional mechanisms. It also makes you eat worse. If you skip breakfast, for instance, you’re likely to pick up a crappy snack when you finally get hungry. Which leads to another factor in the importance of mealtimes—taking the time to prepare something good.
One aspect of the Mediterranean diet that often goes unmentioned is that the meals are usually eaten slowly. Spain’s famously long lunch breaks are actually spent having lunch, often at home with family. By taking time to prepare and eat our meals, we are more likely to eat something healthy. These eating patterns vary a lot around the world. Whereas southern Europe favors proper meals, and the social engagement they bring, up in the U.K. people are more likely to eat alone, at their desk, and to grab whatever is convenient. This, says King’s College, "translates to greater consumption of ready-prepared and take-away meals, more meal skipping and calorie-dense snack foods such as crisps [potato chips]. Thus, the studies’ authors conclude that where and with whom you eat are also important.
And the old chestnut about breakfast being the most important meal of the day? It turns out to (possibly) be true. In the U.K. and U.S., calorie intake increases throughout the day, but big evening meals are bad news. On study cited says found that weight loss and blood-sugar level improved in women who ate more of their calories in the morning. But while big evening meals should be avoided, the role of breakfast isn’t quite clear-cut.
"Although the evidence suggests that eating more calories later in the evening is associated with obesity," says lead author Dr. Gerda Pot, "we are still far from understanding whether our energy intake should be distributed equally across the day or whether breakfast should contribute the greatest proportion of energy, followed by lunch and dinner."
So, to sum up: You should probably start the day with a big breakfast; you should eat regular meals, and they should be properly prepared, and eaten at the table. And wherever possible, you should share meals with others. In short, exactly what your parents always told you to do when you were growing up, but you probably don't have the time to do now.
Have something to say about this article? You can email us and let us know. If it's interesting and thoughtful, we may publish your response.