When someone has “dementia,” that means they are losing their memory or other mental skills, and it’s starting to affect their daily life. Alzheimer’s disease is one of the most common types. But there are many others, too.
Dementia is more common with age. But it’s different than normal age-related changes in your memory.
What makes you more or less likely to get dementia depends on a lot of things. Some, like your genes, you can’t change. But others, you can influence to lower your risk.
Most people with dementia -- 60% to 80% -- have Alzheimer’s disease.
Can you lower your risk? You may be less likely to get Alzheimer’s disease if your weight, blood pressure, blood sugar, and cholesterol levels are normal. The same things that are good for your heart -- like exercise and a healthy diet (think fruits, vegetables, whole grains, and lean protein) are good for your brain, too.
Although there’s no proven way to prevent Alzheimer’s disease, you can lower your risk by taking care of your whole body. Make it a habit to stay active most days.
Also, some studies link staying socially involved and challenging your brain with lower odds of getting Alzheimer’s. This research doesn’t prove that relationships or mentally stimulating activities prevent Alzheimer’s. But there’s no downside to spending time with people you enjoy and learning new things throughout your life.
There are also things that you can’t change that increase your odds.
Certain gene glitches can make you more likely to get Alzheimer’s, or to get it early in life. Although many genes may be involved and one in particular, called apolipoprotein E, or APOE, seems to play a role in Alzheimer’s that starts after age 60.
If you have a certain variation of APOE, you’re more likely to get Alzheimer’s. But you might not. Some people who have it never get the disease. And other people with Alzheimer's don’t have that gene glitch at all. This is why most doctors don’t recommend genetic testing for Alzheimer’s disease.
Other things that increase your likelihood of the disease include:
Multiple strokes that damage brain tissue can cause vascular dementia. It becomes more common with age. But it’s not a normal part of getting older.
By managing your health, you may be able to slow down vascular dementia, and prevent it from getting worse. Talk to your doctor about medications that can also help.
Dementia with Lewy Bodies (DLB)
Protein deposits, called Lewy bodies, develop in nerve cells in your brain over time. This leads to memory loss and problems with movement. This form of dementia makes up about 10% to 25% of all cases. You may also hear it called Lewy body dementia.
Can you lower your risk? Unfortunately, scientists don’t know what causes it, so there’s no clear way to make it less likely.
There’s also no known genetic connection. But men over 60 are most likely to get it. And if you have a family member with Parkinson’s disease or Lewy body dementia, your chances go up.
Parkinson’s Disease Dementia
When you have Parkinson’s disease, you also have protein deposits on your brain called Lewy bodies. Researchers think people with Parkinson’s could also have protein “plaques” and “tangles” in their brains similar to those seen in Alzheimer's disease.
Can you lower your risk? There’s no proven way to do that. No one knows what causes Parkinson’s disease, but in some rare cases genetic changes could be the source. Scientists also think coming in contact with toxins or other things in the environment may increase your risk of getting it.
Other things that raise your odds include:
- Age (your chances go up after age 60)
- Family history (your odds go up if someone in your family has it)
- Gender (men are more likely to develop it than women)
A certain gene glitch causes this brain disorder. It leads to problems with movement and thinking, as well as to dementia. You can start seeing symptoms between the ages of 30 and 50, but as old as age 80.
Can you lower your risk? No. But if it runs in your family, you could ask your doctor about a test to see if you have the gene. The results won’t tell you what symptoms you might have or when they’ll start. But the test can confirm whether you’ll have the disease.
At this time there’s no cure for it, and no way to stop it or slow it down. But there are treatments to help with symptoms.
Creutzfeldt-Jakob Disease (CJD)
This rare disease affects the nervous system.
A protein in the brain starts to change its shape and fold. It then destroys brain cells, which can cause dementia. Although there is no cure, medication can slow down the disease.
There are three types of CJD:
- Sporadic: There is no known cause for this type of CJD.
- Familial: You inherited a CJD gene from a parent.
- Acquired: You got the disease after eating meat infected with “mad cow disease.”
Can you lower your risk? No, except for not eating meat tainted with mad cow disease. Mad cow is very rare, and tainted meat is removed from the market right away. So it’s extremely unlikely that you would get it this way.
Can you lower your risk? Yes, if you eat a healthy diet that gives you enough vitamin B1. If you have a medical condition that puts you at risk, your doctor should make sure you get enough nutrients.
This refers to a group of uncommon disorders that cause the frontal and temporal lobes of the brain to shrink and wither, or atrophy.
Symptoms often appear between the ages of 40 and 75. Doctors don’t know what causes frontotemporal dementia, but your chances might go up if you have a family history of dementia.
Can you lower your risk? There is no known way to lower your risk.
Normal Pressure Hydrocephalus
Doctors don’t know why it happens. But it’s more likely if you’ve had any of the following:
- Brain aneurysm or bleeding, also called a subarachnoid hemorrhage
- Head injury
- Meningitis or similar infections
- Brain surgery, also known as a craniotomy