How Does Too Much Sugar Affect The Brain?

Sugar is a generalized term used to describe sweet, soluble carbohydrates, which are often added to a wide variety of food and drink for a number of reasons. One of the best properties of a sugar is its sweet taste. According to Institute of Food Technologists, sweetness improves the palatability of many foods and adding sugar to foods with high nutrient quality increases the chance they are consumed.

Pretty much all of us know that too much sugar is not good for us. I mean we are already familiar with obesity, hypertension, the metabolic syndrome, type 2 diabetes, and even kidney disease. But why do some of us crave for more crunchy candies or last slice of chocolate cake? And why sugary foods are easy to consume yet so hard to resist? What happens in the brain when you take sugary foods?

The video, How Sugar Affects The Brain, by neuroscientists Dr Nicole Avenue on TED-Ed break downs how sweets and treats neurologically affect us, why they should be enjoyed in moderation and why we get tired of eating the same balanced meal every day.

So what happens when you eat something sugary? The first thing that happens when sugar hits the tongue, as explained in the video, is that it activates the sweet-taste receptors and these receptors send a signal up to the brain stem, which then spreads out into many areas of the forebrain, one of which is the cerebral cortex.

“Different sections of the cerebral cortex process different tastes: bitter, salty, umami and in our case, sweet. From here, the signal activates the brain’s reward system and this reward system is the reason why we want to crave for more sugary foods,” explains the video.

Food is not the only thing that activates the reward system, but also socializing, sexual behavior, and drugs. However, when this reward system is over-activated, a series of unfortunate events such as loss of control, craving, and increased tolerance to sugar starts to impel.

The video further explains, “The major currency of our reward system is dopamine, an important chemical or neurotransmitter. There are many dopamine receptors in the forebrain,but they’re not evenly distributed. Certain areas contain dense clusters of receptors, and these dopamine hot spots are a part of our reward system. Drugs like alcohol, nicotine, or heroine end dopamine into overdrive, leading some people to constantly seek that high, in other words, to be addicted. Sugar also causes dopamine to be released, though not as violently as drugs.”

Sugar can be highly addictive and like drugs, it causes a release of dopamine in nucleus accumbens – the reward center of the brain. Sugary foods and junk foods can cause high dopamine release much more than any foods we found in nature and this is the reason why people who are susceptible to addiction find it hard to resist sugary foods which ultimately leads to addiction. Broccoli, on the contrary, has no effect. No wonder why it is so hard to get kids to eat their veggies.

The brains are also evolved to pay special attention to new or different tastes, so when you keep eating the same dish many days in a row, the level of release of dopamine becomes lesser and lesser and eventually levels out. However, in case of sugar, the dopamine response does not level out. That is why sugar effects on us are much alike to our brain’s reaction to sex and drugs. Watch the video below.

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