Sugar is bad for brain too

Updated about Mar 27, 2017

ISLAMABAD: We know that too much sugar is bad for our waistlines and our heart health, but now there’s mounting evidence that high levels of sugar consumption can also have a negative effect on brain health – from cognitive function to psychological wellbeing.

While sugar is nothing to be too concerned about in small quantities, most of us are simply eating too much of it. The sweet stuff – which also goes by names like glucose, fructose, honey and corn syrup – is found in 74 percent of packaged foods in our supermarkets. And while the World Health Organisation recommends that only 5 percent of daily caloric intake come from sugar, the typical American diet is comprised of 13 percent calories from sugar.

It’s easy to see how we can get hooked on sugar. However, we should be aware of the risks that a high-sugar diet poses for brain function and mental well-being.

Here’s what you need to know about how overconsumption of sugar could wreak havoc on your brain.

It creates a vicious cycle of intense cravings.

When a person consumes sugar, just like any food, it activates the tongue’s taste receptors. Then, signals are sent to the brain, lighting up reward pathways and causing a surge of feel-good hormones, like dopamine, to be released. Sugar “hijacks the brain’s reward pathway”, neuroscientist Jordan Gaines Lewis explained. And while stimulating the brain’s reward system with a piece of chocolate now and then is pleasurable and probably harmless, when the reward system is activated too much and too frequently, we start to run into problems.

“Over-activating this reward system kickstarts a series of unfortunate events – loss of control, craving, and increased tolerance to sugar,” neuroscientist Nicole Avena explained in a TED-Ed video.

In fact, research has shown that the brains of obese children actually light up differently when they taste sugar, reflecting an elevated “food reward” response. This suggests that their brain circuitry may predispose these children to a lifetime of intense sugar cravings.

Heavy sugar intake caused the rats to develop a resistance to insulin – a hormone that controls blood sugar levels and also regulates the function of brain cells. Insulin strengthens the synaptic connections between brain cells, helping them to communicate better and thereby form stronger memories. So when insulin levels in the brain are lowered as the result of excess sugar consumption, cognition can be impaired.

 “Insulin is important in the body for controlling blood sugar, but it may play a different role in the brain,” Dr Fernando Gomez-Pinilla, the study’s lead author, said in a statement. “Our study shows that a high-fructose diet harms the brain as well as the body. This is something new.”

It may cause or contribute to depression and anxiety.

 If you’ve ever experienced a sugar crash, then you know that sudden peaks and drops in blood sugar levels can cause you to experience symptoms like irritability, mood swings, brain fog and fatigue. That’s because eating a sugar-laden donut or drinking a soda causes blood sugar levels to spike upon consumption and then plummet. When your blood sugar inevitably dips back down, you may find yourself feeling anxious, moody or depressed.