Beijing time on November 19th, we all love sweets, but too much sugar in the diet can lead to weight gain, leading to obesity, tooth decay and even diabetes. Many people know they shouldn’t eat candy, ice cream, cookies and cakes, and they shouldn’t drink coke and sugary soda, but sometimes these things are so irresistible, as if our brains were born with this hobby.
Amy Reichelt, a nutrition and neurologist, focuses on how today’s “fat-fat” diet changes the brain. She wants to know how what we eat changes our behavior and whether other lifestyles can be used to reduce brain changes.
Rather, our bodies are run on glucose. Glucose’s English “glucose” comes from the Greek word for “glukos”, which means “sweet”. Glucose provides energy to all human cells, including brain cells (neurons).
Dopamine ‘shock’ caused by sugar eating
From an evolutionary point of view, our primitive ancestors were rotting animals. Sugary foods are a good source of energy, so after a long evolution, humans find sweets especially enjoyable. Foods with disgusting, bitter and sour smells may not have matured or may be toxic or rotting, and can lead to disease.
So, in order to maximize your chances of survival, we develop a natural brain system that makes us like sweets because it is the body’s source of energy. When we eat sweets, the brain’s reward system, the middle-brain edge dopamine system, is activated. Dopamine is a brain chemical released by neurons that is a neurotransmitter that transmits positive messages such as excitement and pleasure. When the reward system is triggered, it reinforces our behavior and makes us more likely to do it again.
The dopamine “shock” from sugar eating encourages us to learn quickly and prioritize finding more of these foods. Modern people are full of sweet, energy-rich foods. We no longer need to search for sugary foods because they are everywhere. Unfortunately, our brains are still functionally very similar to those of our ancestors, and the brain really likes sugar. So what happens to the brain when you over-eat sugar?
Can sugar reshape the brain?
The brain is constantly reshaped and reconnected through neuroplasticization processes. This change may occur in the reward system. Reactive reward pathways are activated by drugs or intake of large amounts of sugary foods, allowing the brain to adapt to frequent stimuli, resulting in a tolerance. As far as sweets are concerned, this means that we need to eat more sugar to get the same satisfaction – a typical characteristic of addiction.
Food addiction is a controversial topic between scientists and clinicians. While our bodies do rely on certain drugs, there is a debate about whether you can also be addicted to food when you need food to survive.
The brain needs sugar, more sugar.
Whether we need food to power our bodies or not, many people have experienced a hunger for food, especially when stressed, hungry or in the face of tempting cakes in coffee shops.
To resist appetite, we need to suppress our natural reaction to indulging in these delicious foods. Inhibitive neuronal networks are essential for behavioral control. These neurons are concentrated in the prefrontal cortex, a key area of the brain involved in decision-making, impulse control, and delayed gratification.
Inhibitory neurons act like the brakes of the brain, releasing a chemical called gamma-aminobutyric acid (GABA). Experimental studies of rats have shown that a high-sugar diet can alter inhibitory neurons. Sugar-fed rats also had more difficulty controlling their behavior and making decisions.
Importantly, this suggests that food does affect our ability to resist temptation, which may be why it is difficult for people to change their diet.
In a recent study, researchers asked participants to rate their desire for high-calorie snacks when they felt hungry and when they first ate. For those who regularly eat high-fat, high-sugar foods, they are more eager to snack, even when they are not hungry. This suggests that regular consumption of high-sugar foods may increase appetite, creating a vicious circle that makes people want more and more high-sugar foods.
Sugar destroys the formation of memory.
Another area of the brain affected by a high-sugar diet is the hippocampus, a key memory center in the brain. Studies have shown that rats who eat high-sugar foods have a reduced memory and can’t remember whether they’ve seen certain objects in a particular location before.
Sugar-induced hippocampus changes are mainly reflected in the reduction of new neurons, which are essential for memory coding, and the increase in chemicals associated with inflammation.
How do I keep the brain away from the effects of sugar?
The World Health Organization recommends that we limit our intake of extra sugar to 5% of our daily calorie intake, or 25 grams (6 teaspoons). One reference is that Canadian adults consume an average of 85 grams (20 teaspoons) of sugar a day, suggesting that for many people limiting the intake of extra sugar is a considerable dietary change.
It’s worth noting that the brain has neuroplasticity, which allows it to return to its previous state to some extent as the sugar in the diet decreases, a process that can be enhanced by physical activity. Foods rich in Omega-3 fatty acids, such as fish oil, nuts and plant seeds, also have neuroprotective effects, boosting the chemicals needed to form new neurons in the brain.
Although changing lifestyle is not easy, it’s hard to give up dessert and always want double milk and sugar when we drink coffee, but the brain will thank you for taking positive action. Everything is difficult at first, but these dietary changes are usually much easier after you start. (Any day)