Training Your Brain to Dislike Junk Food

Sharon Moore November 18, 2013

In his report entitled “Why Humans like Junk Food”, Steven Witherly who has spent the last 20 years studying what makes certain foods more addictive, talks about the different factors that make eating a pleasurable experience. First is the sensation of eating the food – the smell, its texture, how it feels in the mouth, the sound, etc. For instance, food manufacturers would spend millions to determine the most satisfying level of crunch in a potato crisp or the perfect amount of fizzle in fizzy drinks. The second factor is the macronutrient makeup of the food. Companies are in constant chase for the perfect blend of salt, sugar, and fats that will make the brain crave junk food more.

So how does exactly the brain respond to junk food?

There are different things that food manufacturers do to make junk food more appealing to the brain. First is the dynamic contrast. This refers to the combination of different sensations for an ‘enjoyable’ eating experience. Second is the salivary response. According to Witherly, the more that a food causes you to salivate, the more it will swim throughout your mouth and cover your taste buds. For example, emulsified foods like butter, salad dressing, ice cream, and chocolate trigger a salivary response that helps spread the taste of ‘goodness’. Some junk foods also promote the ‘melt in your mouth’ sensation which signals your brain that you’re not eating as much as you actually are. This makes you want to eat more without feeling full enough. Junk food also offers variety, which your brain really likes. We all know that experiencing the same taste over again can lead to a reduction in our desire or appetite to eat. They provide enough taste to be interesting but not too stimulating that your sensory response is dulled.

Junk food also makes your brain believe that it is not going to give you enough calories. That’s why even after consuming a large bag of crisp, you can still eat more. What’s more, junk food triggers memories of past eating experiences. For instance, when you eat something tasty, like cookies or ice cream, your brain immediately registers that feeling. So the next time you see or smell that food, or even hear about it, your brain triggers memories and responses that came when you ate it. This causes the "mouth-watering" craving that you get when thinking about your favourite foods.

How to train your brain to resist junk food

Practise the five-ingredient rule. When shopping for pre-packed snacks, look at the label first. If it has more than five ingredients, don’t buy it. Or if you do, consider it a treat and not an everyday must-have.

Aim for free colours. A 2012 study by Cornell University found that people prefer three food items and three different colours on their plates, compared with more or less of either category. So choose at least three different healthy foods for your snack like a piece of apple, a bite-size of dark chocolate, and a handful of nuts. These foods are very fulfilling yet are much lower in calories. Yum!

Break your snacking habit. Do you always crave for a bag or crisps or a scoop of ice cream every afternoon? As soon as the craving starts, opt for a walk in the park or a glass of smoothie drink.

Make health foods tastier. Add slices of apple and kiwi fruit, and some fresh strawberries and berries in a cup of Plain Greek yoghurt for a delightful, naturally sweet and tasty dessert.

Keep the healthy stuff nearby. If you want to eat more healthy foods, store more of them in your fridge. Junk foods are easy to dig into – you just have to rip open a bag. Well, that is if you have them on hand.