Why is junk food more distracting than healthy food?



Qualified Nutritionist (BSc, MSc, RNutr)
@emmatalkshealth
@EmmaThornton
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19 April 2018

Junk food found to be twice as distracting as healthy food!

If you’ve ever attempted to cut back your intake of fatty, sugary foods, you’ve probably found it impossible to ignore cravings, with the mere sight of a slice of cake sending you salivating. But why does our body react this way to junk food? Is it simply due to past behaviour or  a habit that needs to be broken?

The answer may be ‘yes’ but this explanation certainly isn’t painting the full picture for you. Fortunately, research seems to be backing up the idea that junk food is inherently more distracting than healthy food. A recent study conducted by the Johns Hopkins University found that junk food, compared to healthy food, was twice as distracting for participants.1

As part of the study, participants had to partake in a complex computer programme where they were required to answer questions as quickly and accurately as possible. Meanwhile, images would flash on the periphery of their computer screens, alternating between food products and other miscellaneous objects. Overall, the images of junk food slowed the subjects down twice as much as the images of healthier foods.

This study, though capable of proving the distracting powers of junk food, doesn’t answer why junk food has this power over us. That answer may just lie with arguably the most important organ in your body – your brain!

How does junk food affect your brain?

Your brain is an incredibly complicated organ and even now, despite decades of extensive research and study, scientists are still only scratching the surface. However, the brain does play a role when it comes to fuelling the appeal of junk food. 

Your brain loves sugar

Sugar is more pervasive in your diet now than it ever was with your distant ancestors. In fact, only a couple of centuries ago sugar was a precious and rare commodity and if you wanted a sugar kick, you had to rely on nature’s source of sugar, fruit! 

Back then sugar was a vital source of energy, helping to fuel your body. Sugar or glucose, could be absorbed into your bloodstream, helping to power your brain.2  According to research, the mere taste of sugar can give your brain a boost. This is because it prompts your body to release more serotonin, the happy hormone, into your bloodstream. 

Arguably this mood-boosting quality of sugar creates another problem – it programmes you to perceive sugar as a ‘reward.’ The memory of not only how your food tastes, but also how you felt while eating it, becomes ingrained into your mind and the next time you see a piece of cake, you immediately associate it with getting an instant mood boost. I talk a little bit more about this particular effect in my blog, ‘Is sugar really addictive?

The other problem is that your body struggles to recognise when enough is enough. It struggles to recognise when you’ve had enough sugar which makes it far too easy to overindulge, especially if your body isn’t responding as it should by stimulating feelings of fullness.

Your brain also quite likes fats

Your body needs fat to survive and your brain is no exception – in fact, it’s perhaps the fattest organ in your body. Fat is a key structural component of your brain – around 60% of your brain is estimated to be fat! -  so essential fatty acids like omega 3 and fat soluble vitamins, such as vitamin E, are pivotal for your survival, helping to maintain cell membranes and support the movement of neurotransmitters.

Fat can be stored and used as energy further down the line so you may be drawn to fats as part of a more primordial reflex, similar to sugar. You can also build up a similar reward system with fat as, just like sugar, it can trigger the release of happy hormones like dopamine. Interestingly though, too much fat is thought to over-stimulate the brain, similar to alcohol!

However, if you try and eliminate fat from your diet completely, be prepared to experience some serious hunger pangs. Your body needs the right types of fats such as omega fatty acids and often when you experience a craving, it’s your body crying out for these healthy sources. Unfortunately, instead of choosing good sources of omega fatty acids, such as oily fish, nuts or avocados, you may reach for a packet of crisps in its place! 

And, to compound things, research is now starting to indicate that the more fat you consume, the more your response to fat declines. You won’t be getting the same mood boost you’re used to and so you’ll immediately want to eat more fat, creating a vicious cycle.4  If you want to learn a little bit more about what your cravings could secretly be telling you, please check out my blog ‘What your food cravings really mean.’

Junk food is designed to be more appealing

So, your body craves fat and sugar naturally, recognising them as vital sources of energy. The problem is, that many big junk food companies already know this and have invested millions into trying to make their products as appealing as possible, both visually and when it comes to flavours.

  Real-time and effort goes into getting the right combination of flavours and textures to get that positive response from your brain, so you want to go back for more. Foods that are ‘melt in your mouth’ good are actually the worst – soft crisps, cotton candy etc. You see, because they are broken down so quickly, your brain gets tricked into believing that you’re not really eating that much. The result is that you don’t feel as full as you might otherwise so you continue eating.5 

This type of trickery isn’t unique to melt-in-your-mouth foods either. As I’ve mentioned, your body craves calories because it needs fuel. Most junk food is a combination of fats, sugars and proteins specifically engineered so your brain will immediately respond, wanting to utilise this food intake as a source of energy, which can delay feelings of satiety and promote overeating.

How do I stop eating junk food?

Okay, so junk food is manufactured to appeal to your body and your body is engineered to crave sugar and fat. You can be forgiven for thinking that it seems like a no-win situation, but there are ways you can combat your cravings and override your desire for junk food.

1 – Don’t go too extreme

Here at A.Vogel, we’re not big fans of extreme fad diets that try to have you completely restrict your intake of certain food groups. If you’re used to eating refined carbs and immediately decide to go on a Ketogenic diet then you are going to run into problems and quite rightly, find it difficult to stick to your new eating routine.

 Your body needs fats, carbohydrates and yes, even sugar, but problems often arise because we’re not eating them in the right form. Therefore, making some simple changes rather than giant leaps can go a long way. 

Instead of boycotting bread, try switching to wholemeal bread. This form is not as processed so it will still retain plenty of energy-boosting B vitamins and even some dietary fibre. If you do find yourself experiencing some sugar cravings in the afternoon, try to reach for some fruit first or even some organic cacao chocolate. 

Cacao is arguably the purest form of chocolate, but unlike cocoa, it is raw and not as processed meaning that it still contains plenty of antioxidants and magnesium. My personal favourite cacao chocolate brand is Ombar, whose bars even contain some probiotic properties too! 

2 – Less is more

If you’ve ever checked the label of a food product in a supermarket only to find an incomprehensible list of ingredients, it might be worth putting it back on the shelf. The fewer ingredients your food contains, the better. This means it probably isn’t as processed and won’t contain the same unwanted chemical extras, such as preservatives, artificial sweeteners and flavourings!

3 – Chew your food properly

It might sound like an obvious step but it’s surprising how many of us aren’t chewing our food properly either due to eating on-the-go, or taking our evening meal in front of the television. This can be a problem as chewing is a crucial step of the digestive process, helping to break your food down so it can be digested more easily. Chewing also promotes satiety, making it easier for you to recognise when you are full so you don’t overeat.6 

4 – Taste the rainbow 

As I’ve mentioned, junk food is engineered to be attractive, usually coming in bright colours so as to appeal to our eyes as well as our stomachs. One study in 2012 found that people generally prefer some colour on their plates, often combining three different food groups and three different colours in each of their meals.

  

That’s why I’d recommend loading your plate with brightly coloured fruit and veg – not only are these appealing to look at but colourful fruits and veg are usually loaded with beta carotene and antioxidants! 

5 – Get more involved with your food

The best thing you can do to change your eating habits is to get more involved with your food. It can be easy and convenient to fall back on instant ready meals and quick fixes such as supermarket sandwiches and crisps, but ultimately it won’t be doing any wonders for your health. 

Cooking doesn’t have to be too complicated – nobody has the time to whip up a 5 course meal or prepare an elaborate breakfast. Instead you can take it at your own pace and experiment – not only will this give you a new skillset to explore, it will also instil a greater appreciation of food in general. Our website is full of great simple recipes that are ideal for beginners, whether you’re looking for a warm and comforting soup or an energy boosting snack!

1https://www.sciencedaily.com/releases/2017/10/171026135327.htm

2http://www.bbc.co.uk/science/0/21835302

3http://www.holistichelp.net/blog/what-craving-fat-means/

4https://www.sciencedirect.com/science/article/pii/S0261561411001087

5https://jamesclear.com/junk-food-science

6https://www.ncbi.nlm.nih.gov/pubmed/26188140

7http://news.cornell.edu/stories/2012/01/how-you-plate-food-kids-matters

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