Dementia’s Deadly Trio: Unveiling the Hidden Culprits Behind Cognitive Decline



Who isn’t concerned about brain health? Along with gray hair and wrinkles, you might worry about having more “senior moments,” or even worse, dementia. As you know, lifestyle plays a role in how fast your brain ages and your risk of developing dementia. Environmental exposures do too.

As you know, what you eat and how much you move your body affects brain health (exercise helps form new nerve cell connections) but scientists have also identified other factors. Researchers from the Nuffield Department of Clinical Neurosciences at the University of Oxford looked at data from UK Biobank participants to explore risk factors that affect brain aging. They scrutinized brain scans of more than 40,000 British individuals over the age of forty-five.

Based on the data, they classified so-called ‘modifiable’ risk factors for dementia, as we can affect our exposure to them — into fifteen broad categories: blood pressure, cholesterol, diabetes, weight, alcohol consumption, smoking, depressive mood, inflammation, pollution, hearing, sleep, socialization, diet, physical activity, and education.

New Research Unveils “Weak Spot” in Brain Vulnerable to Dementia

Which factors were the most harmful out of these fifteen? According to the study results, diabetes, alcohol intake, and traffic-related air pollution top the list. Based on the research, scientists identified a “weak spot” in the brain. This brain region is vulnerable to diabetes, traffic-related air pollution — increasingly a major player in dementia — and alcohol. Interestingly, this part of the brain is also more susceptible to schizophrenia, a mental health disorder that causes a wide range of symptoms including delusions and hallucinations.

Prof. Gwenaëlle Douaud, who led this study, said: ‘We know that a constellation of brain regions degenerates earlier in aging, and in this new study we have shown that these specific parts of the brain are most vulnerable to diabetes, traffic-related air pollution — increasingly a major player in dementia — and alcohol, of all the common risk factors for dementia.

Let’s take a closer look at each factor they identified and how they may play a role in brain aging and dementia.

Diabetes and Its Role in Brain Aging

Diabetes is a risk factor for several health issues, including dementia. In fact, diabetes harms every organ in the human body, including the brain. One way diabetes and uncontrolled blood sugars damage the brain is by injuring the tiny blood vessels that carry blood, oxygen, and nutrients to your brain. When diabetes damages these vessels, it reduces blood flow to the parts of your brain that process information.

Plus, research shows that people who have poor blood sugar control have more amyloid-beta plaques in their brain, damaged proteins, that you see in people who have Alzheimer’s disease. In fact, dementia is sometimes called “type 3 diabetes.” That’s why it’s important to maintain good blood sugar control through exercise and diet. It’s also important to manage other risk factors such as lipid abnormalities and high blood pressure.


Some studies show that consuming modest amounts of alcohol could be beneficial for brain health, although research is mixed. However, consuming alcohol in higher quantities is harmful to cognitive function and raises the risk of dementia, as this study shows.

Alcohol harms brain health in several ways:

Alcohol is directly harmful to blood vessels in the brain. Heavy drinking can cause loss of nerve cells in the hippocampus, a region of the brain involved in memory.

Excessive use of alcohol can also lead to B-vitamins deficiencies, particularly thiamin. When you’re low in these nutrients it affects memory and brain function.

By harming heart health through blood vessel damage, alcohol can contribute to heart disease risk and increase the risk of stroke, all of which are harmful to brain health.

Alcohol directly affects cognitive function, as you know if you’ve ever seen someone drunk.

Traffic-Related Air Pollution

The exhaust that comes out of your car doesn’t smell good, but it also may affect the health of your brain over time. Traffic fumes are a mixture of particulate matter, nitrogen oxides, and carbon dioxide. Of particular concern is PM2.5, a fine particulate matter that can easily enter your bloodstream when you breathe it in. Once in your bloodstream, it can travel to your brain.

PM2.5 causes oxidative stress and inflammation in blood vessels, including those that feed. This leads to vascular damage that contributes to cardiovascular disease and dementia. Plus, it may break down the blood-brain barrier, making it easier for pollutants to reach your brain.

Scientists are concerned that air pollution, in general, including wildfire smoke accelerates brain aging. Studies suggest air pollution contributes to changes in brain structure and a reduction in brain volume. Not what you want if you want to stay sharp as you age!

The Bottom Line

While the prospect of cognitive decline and dementia can be daunting, the good news is that we have the power to influence our brain health through our lifestyle choices. By addressing modifiable risk factors such as diabetes, alcohol consumption, and exposure to air pollution, we can take proactive steps to safeguard our cognitive abilities and potentially reduce the risk of neurodegenerative diseases.

Keep this in mind. These risk factors don’t operate in isolation. Rather, they interact with each other and with our genetic predispositions in complex ways. However, by adopting a holistic approach that encompasses proper nutrition, regular exercise, stress management, and environmental awareness, you can slow the rate at which your brain ages.

The key to preserving brain health is to embrace a lifestyle that nurtures and supports your neural pathways. By making conscious choices today, you can pave the way for a future filled with mental clarity, cognitive resilience, and the ability to navigate life’s challenges with sharpness and agility.


  • Jordi Manuello, Joosung Min, Paul McCarthy, Fidel Alfaro-Almagro, Soojin Lee, Stephen Smith, Lloyd T. Elliott, Anderson M. Winkler, Gwenaëlle Douaud. The effects of genetic and modifiable risk factors on brain regions vulnerable to ageing and disease. Nature Communications, 2024; 15 (1) DOI: 10.1038/s41467-024-46344-2.
  • Ehsan Abolhasani, Vladimir Hachinski, Nargess Ghazaleh, Mahmoud Reza Azarpazhooh, Naghmeh Mokhber, Janet Martin. Air Pollution and Incidence of Dementia: A Systematic Review and Meta-analysis. Neurology, 2022; 10.1212/WNL.0000000000201419 DOI: 10.1212/WNL.0000000000201419,
  • Wiegmann C, Mick I, Brandl EJ, Heinz A, Gutwinski S. Alcohol and Dementia – What is the Link? A Systematic Review. Neuropsychiatr Dis Treat. 2020 Jan 9;16:87-99. doi: 10.2147/NDT.S198772. PMID: 32021202; PMCID: PMC6957093.
  • Albai O, Frandes M, Timar R, Roman D, Timar B. Risk factors for developing dementia in type 2 diabetes mellitus patients with mild cognitive impairment. Neuropsychiatr Dis Treat. 2019 Jan 3;15:167-175. doi: 10.2147/NDT.S189905. PMID: 30655669; PMCID: PMC6322491.
  • “Glucose Levels and Risk of Dementia | NEJM.” 29 Feb. 2024, https://www.nejm.org/doi/full/10.1056/NEJMoa1215740.

Related Articles By Cathe:

7 Lifestyle Habits that Lower the Risk of Dementia Even in People at High Risk

2 Health Factors You Can Control that Play a Key Role in Whether You Develop Dementia

Can Strength Training Lower Your Risk of Dementia?

Memory Jolt: Can a Workout Instantly Improve Your Memory?

7 Simple Ways to Preserve Your Brain Health

How High Intensity Exercise Makes Your Brain More Efficient

Is Resistance Training Good for Your Brain Health?

Can the Practice of Yoga Slow Brain Aging?

Exercise is Good for Your Brain as Long as You Make It a Habit

New Research Looks at How Exercise Improves Brain Health

Exercise and Brain Health: Does Working Out Improve Brain Function?

Brain Health, Body Weight and Exercise

Why Squats Might Be the Best Exercise for the Health of Your Brain

Hi, I'm Cathe

I want to help you get in the best shape of your life and stay healthy with my workout videos, DVDs and Free Weekly Newsletter. Here are several ways you can watch and work out to my exercise videos and purchase my fitness products:

Get Your Free Weekly Cathe Friedrich Newsletter

Get free weekly tips on Fitness, Health, Weight Loss and Nutrition delivered directly to your email inbox. Plus get Special Cathe Product Offers and learn about What’s New at Cathe Dot Com.

Enter your email address below to start receiving my free weekly updates. Don’t worry…I guarantee 100% privacy. Your information will not be shared and you can easily unsubscribe whenever you like. Our Privacy Policy