Anyone who, like the rest of the Netherlands, will be working on the tummy bulge after the coming Christmas, would do well to read Radboud neuroscientist Esther Aarts’ new book. In ’Why you always finish a bag of crisps in one go’ (in Dutch), she explains why we can’t stop once we have started on something tasty, how this works in the brain - and how we can prevent it.
Esther Aarts gets it, in her study in the Trigon building of the Donders Institute at Radboud University. You can by no means always do anything about being overweight, or if you regularly overeat. ’The combination of sugar, fat and salt is incredibly rewarding for your brain. That comes from the days when there was scarcity and we couldn’t buy food on every street corner. We are still keen on getting as many calories as possible, in case there is no food left.’ But those days are over. Temptations are everywhere and are hard to resist. ’On top of that, we are creatures of habit and always want to empty our plates. Research also shows that no matter how big you make a portion, people will finish their meal.’
Downward spiral
Our primal instinct does not make it easy for us, especially when we have had a bad day, and we feel we ’deserve’ something tasty. Aarts: ’Of course, that can happen once in a while, but there are people who have a bad day very often and then it becomes a pattern. You can no longer control it and you regularly eat more than you want. At some point it becomes harder for your brain to feel satiety or control.’ Before you know it, you’re in a downward spiral: because you keep eating too much unhealthy food, all those sugars, fats and salts cause your blood vessels to constrict, and those vessels carry oxygen and energy everywhere. ’And if those vessels get just a little clogged, then certain areas of the brain don’t work as well. Which causes you to keep eating, even when you’ve had enough.’
Inflammations
That the brain works differently is also related to inflammations in the body: fatty tissue can become inflamed, especially if there is a lot of fat around organs in the abdomen. Those inflammations can reach the brain, which can have major consequences. Not only does it become more difficult to stay motivated to make healthy choices, but it can also increase the risk of dementia and depression.
Aarts: ’On average, about half of obese people have inflammation. You can’t tell from the outside if someone has it and you don’t feel it yourself, until it goes wrong. We think gut bacteria play a big role in this. We know they have a link to the brain. Gut bacteria regulate the immune system and may be better at preventing inflammatory substances from reaching the brain in some people than in others. We want to explore what role gut bacteria play in protecting for that inflammation.’
Bag of chips in the cupboard
That something needs to be done is clear to the neuroscientist. ’The obesity epidemic is increasing. It is now expected that in 10 years’ time, half the world’s population will be overweight. Even childhood obesity is rising very badly, in the Netherlands as well. If we better understand what that does to our brains, we can tackle it. It’s not about how you look, but the type of obesity associated with that inflammation is very dangerous. It sometimes results in deadly diseases.’
In her book, Aarts explains in an accessible way how your brain works and gives tips on how people can prevent overeating. ’Try to satiate yourself with fibers and good proteins. Eat mindfully and not while watching TV, because then you won’t feel when you’ve had enough. Hide your bag of crisps, don’t put it next to you on the table. If something tasty is around, it is incredibly hard to resist. Your brain goes crazy when it gets tempted that way. So if you want to eat more vegetables, put them in plain sight. Cut them into strips beforehand, make it easy for yourself to make a healthy choice. Give your brain a hand and then your brain will make it easier for you too.’
Esther Aarts’ research into the link between obesity, gut bacteria and the brain requires funding, which will allow Aarts to examine stool samples from participants with obesity from previous projects. Visit the Radboud Fund site for more information.
’Waarom we een zak chips altijd in één keer leegeten’ is available to order online from 17 December and on sale in bookshops from 23 December.
