Everyone has a chance of developing dementia, but some people have a greater chance than others. These people are at 'higher risk'. A 'risk factor' is something that is known to increase a person's chances of developing a condition. For example, ageing is a risk factor for dementia.
Alzheimer's is the most common cause of dementia.
Many people affected by dementia are concerned that they may inherit or pass on dementia. The majority of dementia is not inherited by children and grandchildren. In rarer types of dementia there may be a strong genetic link, but these are only a tiny proportion of overall cases of dementia.
Age is the biggest risk factor: most people with dementia are older than 65 and the likelihood increases as people get older into their 80's and 90's. This tells us that older people are more likely to develop dementia than younger people.
There's no certain way to prevent all types of dementia, as researchers are still investigating how the condition develops. However, there's good evidence that a healthy lifestyle can help reduce your risk of developing dementia when you're older.
Researchers have suggested that people who have more education or do more mentally stimulating activities throughout life build up a higher cognitive reserve, allowing their brain to resist damage caused by disease like Alzheimer's for longer.
For people aged between 65 and 69, around 2 in every 100 people have dementia. A person's risk then increases as they age, roughly doubling every five years. This means that, of those aged over 90, around 33 in every 100 people have dementia.
Stay mentally and socially active. Engaging in mental or social activities may help to build up your brain's ability to cope with disease, relieve stress and improve your mood. This means doing these activities may help to delay, or even prevent, dementia from developing.
Exposure to vitamin D was associated with significantly higher dementia-free survival, compared to no exposure (Figure 2A). The 5-year survival for D− was 68.4% (95% CI: 67.1%–69.7%), while for D+ it was 83.6% (95% CI: 82.3%–84.9%). MCI was associated with lower dementia-free survival than NC, as expected.
The current evidence indicates that while chronic stress may play a role in the development or progression of dementia, it does not necessarily cause dementia. Hopefully, further research can begin to uncover what role stress plays in a person's risk of developing dementia.
Most cases are diagnosed in people aged 45-65.
The Mini-Cog test.
A third test, known as the Mini-Cog, takes 2 to 4 minutes to administer and involves asking patients to recall three words after drawing a picture of a clock. If a patient shows no difficulties recalling the words, it is inferred that he or she does not have dementia.
Vitamin B12 and Folic Acid: Being deficient in both Vitamin B12 and folic acid is common in those with dementia and Alzheimer's disease. Taken together, these two supplements can help lower the levels of an amino acid in the blood that is often linked to dementia.
The research team estimated that 17% of dementia cases could potentially be prevented by increasing vitamin D levels from 25 nmol/L to 50 nmol/L. “In some contexts, where vitamin D deficiency is relatively common, our findings have important implications for dementia risks,” Hypponen said.
A threshold below which the risk of dementia increases markedly has previously been hypothesized to lie in the 25–50 nmol/L range. The optimal level of vitamin D for general health remains controversial, with the Institute of Medicine recommending 50 nmol/L and the Endocrine Society recommending 75 nmol/L.
Administration: The examiner reads a list of 5 words at a rate of one per second, giving the following instructions: “This is a memory test. I am going to read a list of words that you will have to remember now and later on. Listen carefully. When I am through, tell me as many words as you can remember.
Compared with people who didn't walk much at all, people who walked about 9,800 steps per day (about five miles) were 51% less likely to develop dementia. People who walked just 3,800 steps per day (about two miles) were about 25% less likely to develop dementia.
What are the foods that fight memory loss? Berries, fish, and leafy green vegetables are 3 of the best foods that fight memory loss. There's a mountain of evidence showing they support and protect brain health.
Common forms of dementia
Dementia is caused by many different diseases or injuries that directly and indirectly damage the brain. Alzheimer disease is the most common form and may contribute to 60–70% of cases.
How common is dementia? In 2022, it was estimated that there were 401,300 (AIHW estimate) Australians living with dementia. Based on AIHW estimates, this is equivalent to 15 people with dementia per 1,000 Australians, which increases to 84 people with dementia per 1,000 Australians aged 65 and over.
Women have a greater risk of developing dementia during their lifetime. In fact, around twice as many women have Alzheimer's disease – the most common type of dementia – compared to men. The main reason for this greater risk is because women live longer than men and old age is the biggest risk factor for this disease.
Dementia is not a normal part of aging. It includes the loss of cognitive functioning — thinking, remembering, learning, and reasoning — and behavioral abilities to the extent that it interferes with a person's quality of life and activities. Memory loss, though common, is not the only sign of dementia.
Several studies looking at the effect of aerobic exercise (exercise that increases your heart rate) in middle-aged or older adults have reported improvements in thinking and memory, and reduced rates of dementia.
Eating sugar and refined carbs can cause pre-dementia and dementia. But cutting out the sugar and refined carbs and adding lots of fat can prevent, and even reverse, pre-dementia and early dementia. More recent studies show people with diabetes have a four-fold risk for developing Alzheimer's.
Some studies suggest that dietary magnesium is linked to better cognitive function and may reduce dementia risk. One study that followed 1,000 middle-aged adults for 17 years found that those taking the highest levels of magnesium had a 37% lower risk of developing dementia compared to those who took the least amount.