Dementia isn’t just one disease—it’s a word used to describe a group of symptoms that affect the brain.
People with dementia often have trouble remembering things, thinking clearly, controlling their emotions, and doing everyday activities.
It can change how they behave, how they speak, and even how they understand the world around them.
There are many different diseases and conditions that can lead to dementia. Understanding the main causes can help people spot the warning signs, seek help early, and explore treatment options.
The most common cause of dementia is Alzheimer’s disease. Around 7 out of every 10 people with dementia have Alzheimer’s. It slowly damages the brain, leading to memory loss, confusion, and changes in behavior. Scientists believe it may be caused by unusual proteins building up in the brain and disrupting how brain cells talk to each other.
The second most common type is vascular dementia, which makes up about 2 out of every 10 dementia cases. It happens when blood vessels in the brain get damaged or blocked. This reduces the flow of oxygen and nutrients to the brain, which can harm brain cells. Strokes, mini-strokes, or other problems with blood flow are often behind vascular dementia.
Another form is Lewy body dementia, which accounts for about 15% of cases. It’s caused by clumps of abnormal proteins called Lewy bodies. These interfere with brain function and can lead to memory problems, confusion, and movement issues that may look similar to Parkinson’s disease.
Frontotemporal dementia is less common, causing about 5% of dementia cases. It affects the front and side parts of the brain, which control behavior, personality, and language. People with this type of dementia may act in unusual ways, have trouble speaking, or show little emotion.
Parkinson’s disease dementia can develop in people who already have Parkinson’s, a condition that mainly causes shaking and stiffness. Not everyone with Parkinson’s gets dementia, but for some, memory and thinking problems appear several years after movement issues begin.
Some people may develop dementia from Huntington’s disease, a condition passed down in families. Huntington’s affects movement, thinking, and mood, and dementia often appears in the later stages of the illness.
Another rare but serious cause is Creutzfeldt-Jakob disease. This is caused by infectious proteins called prions. The disease progresses quickly and severely affects thinking, memory, and behavior.
Dementia can also be caused by brain injuries, especially if someone has had repeated head injuries, such as in sports or accidents. These injuries can lead to long-term problems with thinking and memory.
Heavy drinking over many years can damage the brain and lead to a type of dementia known as Wernicke-Korsakoff syndrome. This is linked to a lack of vitamin B1, which is essential for brain health.
Finally, not getting enough nutrients, especially vitamins like B1 and B12, can also lead to memory loss and confusion. This can happen if someone eats poorly, drinks too much alcohol, or has a medical condition that makes it hard to absorb vitamins.
In the end, dementia has many causes, but they all affect how the brain works. Some types can be slowed down or treated if caught early.
That’s why it’s so important to learn the signs, know the risks, and take care of your brain through healthy habits, good nutrition, and regular checkups. The more we understand about what causes dementia, the better we can help those who live with it—and possibly prevent it in the future.
If you care about dementia, please read studies about dietary strategies to ward off dementia, and how omega-3 fatty acids fuel your mind.
For more health information, please see recent studies about Choline deficiency linked to Alzheimer’s disease, and what to eat (and avoid) for dementia prevention.
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