Five Ways Sugar Is Ageing Your Brain

Five Ways Sugar Is Ageing Your Brain

Sugar is abundant in the human diet and is a leading factor in declining brain health. While glucose can be important for a quick energy boost, when it’s consumed in excess of our needs, it can also damage and age the brain, leading to cognitive decline, memory problems, and other neurological issues. 

Here are five ways insidious sugar consumption is damaging long-term brain well-being.

1. Neuroinflammation

Sugar consumption can contribute to inflammation throughout the body, including in the brain, which can cause damage to brain cells, nerves, blood vessels and other tissues. Chronic inflammation has been linked to a range of neurological disorders, including Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis. Diets that are high in sugar and processed foods have been shown to increase inflammation contributing to the development of neuroinflammation and disease.

Studies have shown that a high-sugar diet can result in increased inflammatory cytokines (messenger chemicals) in the brain. This puts the brain at significant risk for future cognitive decline and memory problems. One study suggests that consuming a high-sugar diet for as little as two weeks could increase inflammation in the brain and impair cognitive function.

2. Oxidative Stress

Sugar consumption can elevate our burden of oxidative stress, which causes cellular damage and is a known risk to brain well-being. Oxidative stress occurs when there is an imbalance between free radicals (damaging molecules) and antioxidants (protective compounds) in the body which offset damaging chemicals and protect cellular health. A diet high in sugar and processed foods can be highly inflammatory and contribute to oxidative stress. This places great demands on our antioxidant systems, which can quickly become depleted if these kinds of dietary choices are a regular occurrence. 

Studies have shown that consuming a high-sugar diet will increase oxidative stress levels in the brain, contributing to cognitive decline. Furthermore, researchers have also identified that oxidative stress itself can also cause further disruptions to glucose metabolism, and this mechanism has been suggested as a contributor to the development of Alzheimer’s disease. Alzheimer’s disease has such a close connection to blood sugar control that it has been dubbed ‘type 3 diabetes’

3. Insulin Resistance

Chronic, long-term sugar consumption is a pathway to insulin resistance when our sugar regulatory systems become worn out from constant exposure combined with poor nutrition and lack of physical activity. 

Insulin is like a taxi that transports glucose from the blood (outside our cells) to the inside of our cells, where it can be burned for energy. Insulin resistance occurs when the body becomes less responsive to insulin, which prevents it from transporting sugar properly, inevitably leading to dangerous rises in blood sugar levels. 

Insulin resistance is often a preceding factor in type 2 diabetes and research shows that individuals with type 2 diabetes have a much higher risk of developing cognitive decline and dementia. Multiple studies cite poor insulin control as a key clinical feature of Alzheimer’s Disease.

4. Glycation

Sugar consumption can also cause cellular damage through a process called glycation. This occurs when sugar molecules bind to proteins or fats in the blood, forming advanced glycation end products (AGEs). Elevated AGEs are highly inflammatory and associated with many chronic conditions, including cognitive decline and metabolic disease. A diet high in sugar and processed foods, as well as certain cooking techniques, can increase the production or exposure to AGEs in the body, which can have a deteriorating effect on brain and nervous system health. 

In a review published in the journal Nutrients examining a large number of studies, researchers concluded that AGEs are a strong risk factor for cognitive impairment and are also associated with neurological disorders, especially dementia, and mental disorders, such as depression and schizophrenia.

5. Neurotransmitter Imbalance

Finally, sugar consumption can also lead to mood (neurotransmitter) imbalances, which can affect cognition and memory. A diet high in sugar and processed foods can disrupt the nutrients needed to maintain balance in neurotransmitter production. Your body relies on many nutrients such as B vitamins, zinc and amino acids to make beneficial mood chemicals. Diets that are high in sugar also demand many of the same nutrients to enable you to metabolise the sugar and turn it into energy. Therefore, a poor quality diet both lacks essential nutrients for many of these important pathways, but it also costs you valuable nutrients in dealing with the excess sugars. 

Research has shown that a high-sugar diet can affect dopamine and serotonin signalling in the brain, which can contribute to low mood as well as cognitive and memory problems. Disruptions to serotonin and dopamine pathways not only make our mood lousy, but can ramp up our desire for more unhealthy, sugary foods, creating a vicious downward spiral for brain health. A study published in Translational Psychiatry also showed that high-sugar, high-fat diets disrupt the gut microbiome, damage the intestinal tract, and change the neurotransmitter metabolism in the intestine and brain (via the gut-brain connection). 

Sugar Robs You Of Your Brain Well-Being.

Excessive sugar consumption can shave years off your brain health. Your brain is the body’s primary operating system and should be protected and nourished at all costs. 

Sugar steals your cellular longevity through elevated inflammation and oxidative stress. High-sugar diets are also typically very nutrient-poor, which sets you on a path to chronic illness through insulin resistance, glycation, and mood imbalances. 

With Alzheimer’s disease and dementia among the top three leading causes of death, it couldn’t be more important to focus on maintaining quality, long-term brain health and preventing cognitive decline by being mindful of limiting sugar intake as much as possible. 


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