Niki Bezzant
Are you a snacker? I think most of us are these days, since we’re surrounded by eating opportunities and snack food marketing.
Snacking wasn’t really a thing, back in the day, in many cultures. But now as we move towards the same diet everywhere in the world, more of us are grazing our way through the day.
That can have good and bad effects. On the downside, it might throw our body clocks out and encourage overeating and obesity.
A recent University of Virginia study has demonstrated a link between the pleasure centre of the brain, which produces the chemical dopamine, and the brain’s separate biological clock that regulates daily physiological rhythms. When we eat a high-fat, high-sugar, energy-dense diet (foods that stimulate the pleasure centre), the researchers say, it disrupts our body’s normal “feeding schedules” and what they describe as “timed metabolic processes”, driving us to eat energy-dense snacks and eventually gain weight.
This was a mouse study, which is worth noting, but it’s fascinating still. The researchers found mice fed a diet comparable to a wild diet in calories and fats maintained normal eating and exercise schedules and normal weight.
But mice fed high-calorie diets laden with fats and sugars began “snacking” at all hours and became obese.
Previous studies have shown that when mice eat high-fat foods between meals or during what should be normal resting hours, the excess calories are stored as fat much more readily than the same number of calories consumed only during normal feeding periods. This eventually results in obesity and related diseases such as diabetes.
We don’t have to go far to see this scenario playing out in humans. Traditionally in China, for example, snacking was not a part of daily life. But there’s been a huge transition in that country: in kids, for example. In 2004, only 28 per cent of children between 2 and 6 ate between meals. By 2009 that had increased to 59 per cent, and we can assume it’s kept rising. Alongside that there has been a terrifyingly rapid increase in childhood obesity, with one in five Chinese children now overweight or obese, up from just 1 in
20 in 1995.
We can’t say this is all due to snacking, of course. It’s thought to be related to rapid economic growth, increasing urbanisation and the availability of a lot more Western-style processed food across the board. The behavioural change is part of that picture. On the other side, there is some research to show snacking can be a good thing. This comes down, basically, to quality. If kids are snacking on fruit this is associated with lower BMI and higher fibre intakes.
For adults it’s no different. If we consider snacks might make up a quarter (or more) of our daily energy intake, it’s worth aiming to get goodquality nutrition from them, rather than thinking of them as treats that don’t really count. That means making them whole foods as much as possible.