If your father or mother had Alzheimer's, your chances are somewhat higher. Higher is not the same as certain. The large majority of people with Alzheimer's have no affected parent, and most children of an affected parent never develop it.
Heredity is a weight on the scale. It is not the scale itself.
Is Alzheimer hereditary?
Usually not in the way people fear. There is a rare form that passes directly from parent to child, and it often starts before the age of 65. That form accounts for a small share of all cases. The common form works differently: susceptibility raises your odds, and no more than that.
The Hersenstichting, the Dutch brain foundation, draws the same distinction. Susceptibility is not a susceptibility to certainty.
How does it differ from vascular dementia?
In Alzheimer's, proteins build up in your brain and nerve cells are slowly lost. In vascular dementia the small blood vessels in your brain get damaged, usually after years of high blood pressure or high cholesterol. Many people have both at once.
| Alzheimer | Vascular dementia | |
|---|---|---|
| What goes wrong | Protein build-up, loss of nerve cells | Damage to small blood vessels |
| Course | Usually gradual | Often in steps |
| First complaints | Often memory | Often slowness and concentration |
| Role of blood pressure | Present, indirect | Large and direct |
| Visible in blood? | No | The risk factors are, the damage is not |
That distinction is not academic. It decides how much influence your lifestyle has.
Can you prevent Alzheimer's?
Prevent is too big a word. Lowering your chances is possible. A large meta-analysis of modifiable risk factors in Alzheimer's found a series of factors linked to higher or lower risk, from blood pressure and diabetes to education and smoking (Xu et al., 2015).
In 2024 the Lancet Commission arrived at fourteen such factors, together accounting for an estimated 45 percent of all dementia cases (Livingston et al., 2024).
What strikes me every time: the list is boring. Blood pressure, blood sugar, cholesterol, exercise, smoking, hearing. Not a miracle cure in sight, and that is exactly why I trust it.
The full overview is in preventing dementia.
Do supplements help against Alzheimer's?
Without a deficiency, probably not. A meta-analysis of B vitamins found a modest effect on cognitive decline, mainly with long-term use and in people who did not yet have dementia. In people with dementia it did not help (Wang et al., 2022).
So topping up a deficiency makes sense. Taking pills as a precaution without one makes much less.
And whether you have a deficiency is something you only know once it is measured.
Should you get tested for susceptibility?
For the common form of Alzheimer's there is no useful susceptibility test you can simply go and take. A result would hand you a number you cannot act on, and it changes no treatment. For the rare inherited form, testing runs through a clinical geneticist, and always with counselling.
What you can have measured are the factors you can then actually do something about.
That may sound like thin comfort. I think the opposite: it is the only information that gives you something to do.
An example from practice
An example helps here. Picture a woman of 61 whose mother developed Alzheimer's at 78. She sleeps badly from worrying about it. Her blood pressure is 152 over 94, her LDL cholesterol 3.9 mmol/l, and she has moved little since retiring.
She can change nothing about her mother. She can change those three things.
That is exactly why an article about heredity ends up being about blood pressure and cholesterol. Inherited susceptibility is the background. The rest is the foreground, and you are standing in it.
Where do you start?
With the factors you can measure. You take your blood pressure at home or at the GP. Your LDL cholesterol and your blood sugar sit in your blood. You have your hearing checked at an audiologist. The RIVM tracks dementia figures in the Netherlands, and those rise mainly through an ageing population.
What a raised cholesterol means at your age is covered in cholesterol values by age. Why your blood vessels and your brain are so tightly linked is covered in preventing a stroke or brain haemorrhage.
If you want to know where you stand, a lipid screening is a concrete start. If you already notice memory complaints, see your GP first, and read when forgetfulness is normal.
References
- Xu W, et al. (2015). Meta-analysis of modifiable risk factors for Alzheimer's disease. J Neurol Neurosurg Psychiatry. PMID 26294005.
- Livingston G, et al. (2024). Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission. The Lancet. PMID 39096926.
- Wang Z, et al. (2022). B vitamins and prevention of cognitive decline and incident dementia. Nutrition Reviews. PMID 34432056.
- Hersenstichting. Alzheimer and heredity. hersenstichting.nl.
- RIVM. Figures on dementia in the Netherlands. rivm.nl.
Would you like your cholesterol and blood sugar checked at a calm moment, without first booking an appointment with your GP? At Levenswijs Health you can. Every result is reviewed by a doctor registered in the Dutch BIG register. A blood test does not provide a diagnosis and cannot detect or predict Alzheimer's. For treatment decisions, always discuss your results with your GP.
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