How Sugar Affects Your Brain

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How Sugar Affects Your Brain


What do your taste buds scream for on a sweltering hot day?


Ice cream of course!


Even the healthiest nut cannot resist the lure of a sweet and refreshing treat on a humid summer day, especially when there is vanilla involved!


You can indulge in sweet treats occasionally. There is nothing wrong with surprising your taste buds with a piece of chocolate or a homemade cookie. Unfortunately, problems surface when we overdo sweets.


The bittersweet truth

As the most energy demanding organ of the body, the brain runs on glucose, a form of sugar. If blood sugar drops down to critical levels, the breakdown of communication between neurons (chemical messengers in the brain) is inevitable. The brain needs a steady stream of sugar-fuel to carry on its functions like thinking, memory, and learning.


Now, this certainly does not mean that the brain runs on puff pastry, candy, and summery drinks topped with whipped cream. What makes or breaks the system in the brain and the overall functioning of the body is the kind of foods that we regularly consume.


After you ingest a sugary cereal, your taste buds pick up the sweet signal and send it to the cerebral cortex, the wrinkly outermost layer of the brain. The signaling leads to activation of the reward system, triggering the release of "feel good hormone," dopamine. 


The activation of the reward system is evolutionarily beneficial because it motivates us to engage in behaviors that are crucial for our survival. Every time you activate the reward system by socializing with friends or eating your grandmother's cookie, your brain releases dopamine and gives you pleasure.


Neuroscientist Nicole Avena explains in a TED-Ed video that if you eat a balanced meal, you still get a dopamine release from the brain. However, if you eat the same meal every day, you no longer derive pleasure out of it and dopamine levels out.


If you replace the balanced meal with one that is high in sugar, you will still get a dopamine release and feel rewarded. If you consume too many sweets, however, dopamine does not level out and stays high. In turn, you build a higher tolerance for sweets.


Dr. Avena explains, "Over activating this reward system kick starts a series of unfortunate events: loss of control, craving, an increased tolerance to sugar." 


That is one of the reasons why sugar can become addictive and emotionally painful to let go.


Mental health problems linked with high sugar intake in men

University College London (UCL) researchers link high sugar intake with long-term mental health issues in a recent study.


Senior author, Professor Eric Brunner (UCL Institute of Epidemiology and Public Health) and colleagues examined sugar consumption and incidence of mental health disorders in more than 5000 men and 2000 women. The follow-up period for this study was 22 years between 1983 and 2013.


Men who consumed more than 67 grams of sugar per day (from sugary food and beverages) had a 23% increased chance of developing mental health issues after five years. This finding was independent of health related behaviors, socio-demographic and diet related factors.


To put it in perspective, 67 grams of sugar equals thee muffins or 4-5 scoops of regular vanilla ice cream. World Health Organization recommends adults and children to reduce their added sugar intake to 25 grams/6 teaspoons per day for optimal health.


Men and women who had a serious sweet tooth along with a mood disorder were at an increased risk for depression after five years. However, researchers point out that this finding could be related to other health and diet related factors.


Anika Knüppel who the lead author of the paper states that "There are numerous factors that influence chances for mood disorders, but having a diet high in sugary foods and drinks might be the straw that breaks the camel's back."


The researchers did not find a link between high sugar diet and new mood disorders in women.


We are leaving you with this

Indulge in sweets every now and then but do not forget to nourish your brain with healthy, balanced and nutritious foods. Your brain will thank you in the long run!









nutrition, neuroscience, psychology, addiction


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