The Sweet Deception: Revealing Sugar’s Effect On The Brain

It is well known that sugar is not good for the body. What is lesser known is how sugar affects the brain. Sugar can have detrimental effects on the brain that lead to a variety of mental health conditions including but not limited to depression, anxiety, irritability, anger, schizophrenia, dementia, and Alzheimer’s. In this article, we reveal sugar’s sweet deception and how it can have a life-altering effect on the brain.

Insulin Resistance In The Brain

Insulin resistance is caused by chronic overconsumption of carbohydrates (carbs) that are converted into glucose (sugar) in the body. Carbs, primarily processed carbs, cause a dramatic spike in insulin. Over time this causes cells to become resistant to insulin. Insulin-resistant cells cannot absorb glucose effectively causing chronically high blood glucose levels.

Once cells become resistant to insulin, the brain begins a downward spiral of dysfunction. Neuroglial cells called glia are responsible for neuron function and signaling. Glia is responsible for transmitting signals throughout the body that allow us to coordinate bodily functions.¹ It is also responsible for removing dead or damaged cells (cellular debris). When glia becomes insulin-resistant it becomes lazy. It can no longer clean up cellular debris, which results in inflammation in the brain and the death of healthy brain cells.

In the end, this results in a brain that does not function correctly, leading to mental health complications such as depression, anxiety, emotional outbursts, schizophrenia, and even dementia. Research has found that diabetics (a condition caused by insulin resistance) are 3x more likely to have depression compared to non-diabetics.² The brain cannot function properly on a diet high in sugar and processed carbohydrates.

Sugar’s Effect on Dopamine

Dopamine is a neurotransmitter in the brain that controls processes such as mood, behavior, learning, sleep, and memory. It is also responsible for mediating pleasure responses in the brain. Dopamine is released during pleasurable activities, such as eating, sex, exercise, and even drug abuse.³ It causes a natural desire to seek out pleasure.

Sugar can disrupt dopamine levels over time as the brain becomes resistant to insulin. Science has found that both gene expression – the process in which information is encoded into a gene and turned into a function, and dopamine receptors can be altered by long-term sugar consumption.⁴ Altered gene expression can lead to dysregulation of stress responses (an inability to manage stress) and insomnia. Damaged dopamine receptors result in a state of anhedonia or a loss of pleasure or interest in activities that were once enjoyed.⁵ The damaged receptors also result in a lack of motivation, anxiety, depression, sleep issues, and even motor imbalances.

Sugar’s Effect on the Brain

High blood glucose levels can impact the brain’s functional connectivity, negatively affecting brain matter. This can lead to brain atrophy-loss of connectivity between brain cells and neurons or brain shrinkage.⁶ Additionally, high blood sugar can cause small-vessel disease, restricting blood flow in the brain, resulting in cognitive difficulties and potentially leading to vascular dementia.

Research has found that people with type 2 diabetes⁷, a condition caused by long-term overconsumption of carbohydrates and sugar, have increased rates of brain aging. Accelerated brain aging results in accelerated loss of brain function leading first to mental health conditions such as depression and anxiety, then progressing into dementia and Alzheimer’s disease.

The Sweet Deception

Our brains are hardwired to seek out sweet treats. During the years in which humans had to forage for food, sweet treats, such as berries were a rare delicacy. They activated our rewards system and the brain has sought after the pleasure response of sweetness ever since.

The issue now is that sweet treats have evolved well past their original healthy serving of fruit. Instead of a handful of blueberries, we satisfy our pleasure receptors with a handful of processed sugar products. The consumption of sugar gradually leads to the brain’s ultimate demise. As insulin resistance sets in, the brain begins losing its ability to function properly, leading to damaged dopamine receptors, cell damage, brain atrophy, and brain shrinkage. The result is a slew of mental health conditions and brain disorders. Depression, anxiety, irritability, schizophrenia, dementia, Alzheimer’s, and many more including sleep disorders and brain fog, are very often the result of a brain that is being damaged by sugar.

The Solution

The good news is that the brain is very resilient and can recover from damage caused by high glucose and insulin resistance. But in order to do that we must say goodbye to the processed sweets.

The brain does not like sugar. Keeping your brain healthy is worth cutting sugar out of your life. Although sugar is a very addictive substance, the long-term effects on your mental health fully outweigh the short-term withdrawal that you may experience when you quit sugar. The short-lived enjoyment you receive from the momentary taste of sugar is not worth a lifetime plagued by mental health conditions and brain disorders.

Make The Switch

When you need a sweet treat reach for fruit or sweet vegetables rather than processed sugary treats. Fruit and vegetables can satisfy your sweet tooth and reduce your sugar cravings while providing important nutrition to your body. If fruit and veggies on their own don’t do the trick try adding healthy snacks to go with your sweet treat.

Dip your bananas, apples, and carrots in sugar-free peanut butter, or make a fruit parfait with plain Greek yogurt. Dressing up your fruit and veggies with healthy sides is a great way to make fruit feel like a decadent dessert. As an added bonus, including sugar-free peanut butter or plain Greek yogurt, will increase your protein consumption for the day. It’s a win-win!

You will be amazed at how quickly you’ll see a difference in your mental health and brain function once you’ve eliminated sugar. We know it’s not an easy transition but you’ve got this! Give yourself time to transition away from eating processed sweets. At first, your cravings for processed goodies will likely be strong. As your body detoxes from the manufactured snacks the cravings will begin to subside.

You deserve a long life with a healthy brain, free of mental health complications.

Supporting Research

1. RICHARDS, S., & HUTCH, F. (2023, November 7). Insulin resistance turns tidy brain cells into slobs — which could be a link between diet and neurodegenerative diseases | Fred Hutchinson Cancer Center. https://www.fredhutch.org/en/news/center-news/2023/11/rajan-alassaf-glia-insulin-resistance.html ↩︎
2. Bădescu SV, Tătaru C, Kobylinska L, Georgescu EL, Zahiu DM, Zăgrean AM, Zăgrean L. The association between Diabetes mellitus and Depression. J Med Life. 2016 Apr-Jun;9(2):120-5. PMID: 27453739; PMCID: PMC4863499. ↩︎
3. Mandal, A. (2023, June 21). Dopamine Functions. News Medical Life Science. https://www.news-medical.net/health/Dopamine-Functions.aspx ↩︎
4. Flaggert, O. (2022, November 15). The effects of a high sugar diet on the brain – tind neurology. Texas Institute for Neurological Disorders. https://www.texasinstituteforneurologicaldisorders.com/uncategorized/effects-high-sugar-diet-brain/#:~:text=Sugar%20can%20also%20disrupt%20dopamine,a%20long%20period%20of%20time. ↩︎
5. Butler Center for Research. (2015, September 1). Drug abuse, dopamine and the brain’s reward system. Drug Abuse, Dopamine and the Brain’s Reward System. https://www.hazeldenbettyford.org/research-studies/addiction-research/drug-abuse-brain#:~:text=Reduced%20dopamine%20receptors%20also%20result,state%20of%20low%20self%2Dcontrol.&text=Self%2Dcontrol%20is%20further%20reduced,regulating%20the%20brain’s%20reward%20system. ↩︎
6. Edwards, S. (2016, Spring). Sugar and the Brain. Harvard Medical. https://hms.harvard.edu/news-events/publications-archive/brain/sugar-brain#:~:text=High%20blood%20glucose%20levels%20can,brain%20to%20atrophy%20or%20shrink. ↩︎
7. Detecting Diabetes: 9 Proven Symptoms To Watch Out For. Human Health Co. (2024b, April 24). https://humanhealthco.com/detecting-diabetes-9-proven-symptoms-to-watch-out-for/ ↩︎