Rubbish In, Rubbish Out – The Effect Of Junk Food On Our Behaviour

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Rubbish In, Rubbish Out – The Effect Of Junk Food On Our Behaviour

It’s standard practice the world over to treat psychological disorders psychologically. Mood swings, depression, suicidal tendencies, paranoia and schizophrenia, among others, are all treated with counselling, psychiatric drugs and/or electro-shock therapy. These treatments are unarguably effective – and necessary – in many cases of mental disorders. However, there is a growing awareness of the efficacy of alternative approaches – especially when it comes to the role our physical chemistry has on our mental wellbeing. The food we eat feeds our blood, which in turn feeds our brain. So when it comes to what we put in our mouths, what exactly is the effect of junk food on our behaviour?

A clinical study in the American Journal of Clinical Nutrition showed that people who ate too many refined carbohydrates exhibited neurotic tendencies. Personality changes, particularly among adolescents, included: sensitivity to criticism, poor impulse control, frequent irritability, hostile behaviour, and short tempers. It also reported other problems, such as sleep disturbances, chronic debilitating fatigue, depression, recurrent, unexplained fevers, abdominal and/or chest pains and headaches. In addition, patients were also found to be deficient in vitamin B1 (thiamine).

The Effect Of Junk Food On Children

Sugar is the usual, go-to culprit when it comes to finding reasons for bad behaviour in children. There is good reason for this, but other unhealthy ingredients can also cause changes in the way children behave. The European Journal of Clinical Nutrition cites artificial colours and preservatives as key culprits for behavioural problems.

The problem is, once children get a taste for fatty, sugary foods, they begin to crave them. Studies show that simple carbohydrates stimulate the regions of the brain associated with satisfaction and reward. In other words, children love junk food not only because it tastes so good, but also because it makes them feel good. This feeling can become addictive, causing children to prefer junk food to healthier options, such as fruit and vegetables.

Junk Food And Hyperactivity

There is a perceived link between a diet high in sugar and hyperactivity in children. While more study in this area is needed, there is undoubtedly validity in the claim. Refined sugar reaches our bloodstream quickly, causing a rapid rise in blood sugar. This can cause hyperactivity in children. There is a particular link between fizzy drinks and attention and concentration deficits in children.

Junk Food And Aggression

Studies show a link between a diet high in junk food, and an increase in violent, aggressive behaviour in children. One study, in particular, published in “Injury Prevention,” states that children who drink five or more fizzy drinks a day were up to 15 percent more likely to be aggressive to family members.

How Does Junk Food Affect Our Brain?

You’ve probably noticed short-term changes in your mood after eating a certain food. The distinct “sugar high” after eating too many sweets, for example. Or bad-temperedness when you’re hungry. But what you eat also affects your brain in the long-term, too.

In a study in the American Journal of Clinical Nutrition, otherwise healthy people who only ate junk food for five days performed poorly in cognitive tests measuring mood, speed and attention. Diets high in fat and sugar can suppress the activity of a peptide in our brain called BDNF, which helps us with memory formation and learning. High-calorie diets can also interfere with the healthy production and functioning of synapses in our brain.

In addition, eating too many fatty or sugary foods can increase our resistance to insulin. When our brains stop responding to insulin, it affects our ability to think and create new memories. Poor diet has also been positively linked to dementia, as high blood pressure and cholesterol disrupt the blood supply to the brain.

Of course, many people suffering from behavioural issues and psychological disorders have causes that are not diet- or body chemistry-related. But in the light of such convincing and overwhelming evidence that what we eat definitely influences our behaviour, diet-related causes should, at the very least, be thoroughly explored, and not simply discounted out of hand.

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