When we think about brain health, it can be easy to forget that the brain doesn’t exist in isolation but is intricately connected to every other organ, tissue and nerve cell in our bodies.
The fact is that the health of your heart, the quality of your sleep and even the state of your gums can all affect your risk of developing dementia – now the UK’s biggest killer.
‘Our brain is the centre of a continuous body-wide conversation,’ explains Paresh Malhotra, a professor of clinical neurology at Imperial College London.
‘It reaches down through the spine and is in constant communication with the rest of the body through blood vessels and nerves – so that every breath we take, every heartbeat, movement and all the sensations we experience form part of an ongoing loop of information and responses.’
This is why experts say taking care of your whole body is one of the most powerful ways to protect your brain into old age – including helping to reduce the risk of dementia (a set of symptoms caused by more than 100 brain diseases including, most commonly, Alzheimer’s).
It’s true that genes play a role, yet millions of cases of dementia could be prevented with lifestyle changes – such as tackling hearing loss, high blood pressure and social isolation, according to a report this month by Queen Mary University of London.
The researchers said: ‘In the absence of a cure or wide access to effective treatments, prevention is key to addressing the increasing impact of dementia.’
This follows a landmark 2024 Lancet Commission Report, which found that nearly half of all dementia cases (45 per cent) could be avoided by adopting a healthier lifestyle and addressing some common health conditions.
The good news is that it’s never too late to start. To help you, in this exclusive pullout we have assembled a panel of leading experts, offering advice based on the latest scientific evidence.
When we think about brain health, it can be easy to forget that the brain doesn’t exist in isolation but is intricately connected to every other organ, tissue and nerve cell in our bodies
Everyone experiences dementia differently. Use this checklist to help you make a note of your symptoms before you talk to your GP.
Health problems that raise your risk
What many people don’t realise is that common health conditions can significiantly increase the chances of developing dementia.
Fading eyesight
Addressing eyesight issues can hep stave off dementia
Uncorrected vision issues, particularly in middle and later life, can increase your dementia risk by 50 per cent, according to Alzheimer’s Society. Visual impairment can lead to social isolation and reduced physical activity – both dementia risk factors, says optometrist Louise Gow, from the Royal National Institute of Blind People. ‘If your vision is poor you might struggle to read, see people’s faces and pursue your hobbies, making you reluctant to go out, so you could become lonely, which increases dementia risk.’
And correcting vision problems really could help. Studies have shown people who had cataract surgery reduced their risk of dementia by 30 per cent.
Insomnia
People consistently sleeping less than six hours a night in middle-age are 30 per cent more likely to develop dementia, according to 2021 research in Nature Communications.
‘Consistent poor sleep interferes with your brain’s ability to clear out toxins, including the protein beta amyloid, linked to Alzheimer’s,’ explains Professor Guy Leschziner, a consultant neurologist at Guy’s and St Thomas’ NHS Foundation Trust in London.
Chronic insomnia (difficulty falling and staying asleep lasting more than three months) can also lead to raised blood pressure, lowered immunity and depression – all dementia risk factors.
But sleeping tablets are not the answer long-term – benzodiazepines and ‘z’ drugs used over time may be linked to cognitive decline as they may affect brain chemicals important for memory.
‘Ask your specialist or GP to review your prescriptions,’ says Professor Leschziner.
High blood pressure
This is ‘the biggest modifiable factor causing memory loss in Britain’, says Adam Greenstein, a professor of medicine at the University of Manchester.
High blood pressure narrows arteries, reducing the oxygen and nutrient supply to the brain, while also reducing fluid drainage from it, which can lead to vascular dementia as well as to the build-up of proteins linked to Alzheimer’s. It’s also a major risk factor for strokes, which directly damage brain tissue.
‘One in three Britons has high blood pressure, but half don’t know it,’ says Professor Greenstein.
Getting your blood pressure checked lets you see if you have a key dementia risk factor
Infection from gum disese can travel to the brain if not dealt with
Hearing loss
The Lancet Commission Report found those with hearing difficulties were 40 per cent more likely to develop dementia than those with good hearing.
Even mild hearing loss can contribute to an increased dementia risk, says the report’s lead author, Gill Livingston, a professor of psychiatry of older people atUniversity College London.
‘It may lead to social isolation, loneliness and moving less, known dementia risks, as people withdraw from conversations and activities.’
Lack of auditory stimulation may also cause structural changes in the brain, with studies showing accelerated brain shrinking in people with hearing loss, particularly affecting areas concerned with memory.
Wearing hearing aids can reduce the risk. Studies, involving nearly 17,000 people with hearing loss, found those who wore hearing aids reduced their dementia risk by 17 per cent compared with those who didn’t.
High cholesterol
High levels of ‘bad’ LDL cholesterol puts you at a 30 per cent increased dementia risk. It causes fatty deposits to build up in the arteries, but often goes undetected until it causes a heart attack or stroke – both dementia risks.
High LDL cholesterol can also contribute to harmful amyloid plaque build-up in the brain.
‘Amyloid may be carried through the bloodstream by cholesterol, crossing the blood-brain barrier,’ Professor Livingston explains. ‘So higher cholesterol levels mean more amyloid is deposited in the brain.’
A ‘healthy’ LDL level is 4mmol/L or below.
A diet high in cholesterol could play a part in the onset of dementia
Type 2 diabetes
This can triple your chances of developing Alzheimer’s, as high blood sugar levels are thought to lead to a build-up of amyloid deposits in the brain.
Both high blood sugar and high insulin can damage the brain’s blood vessels, disturbing control of its chemicals, says Paresh Malhotra, a professor of clinical neurology at Imperial College London. Losing weight can often reverse the condition.
Sleep apnoea
This serious condition, where sufferers stop breathing temporarily while sleeping, can lead to intermittent oxygen starvation of the brain and interrupted sleep, raising dementia risk.
‘Intermittent oxygen deprivation damages brain cells over time, and causes inflammation of the brain tissue,’ explains Adam Frosh, a consultant ear, nose and throat surgeon at East and North Hertfordshire NHS Trust and a specialist in treating sleep apnoea. ‘Fragmented sleep also interferes with REM sleep, [rapid eye movement sleep, when dreaming occurs] when the brain’s cleaning system clears out toxic amyloid proteins, linked to Alzheimer’s.’
TYPES OF DEMENTIA
Dementia is not a single disease but is an umbrella-term for conditions that damage the brain, interfering with daily life.
Different types may have different symptoms, particularly in the early stages, according to which part of the brain has been affected.
There are more than 100 different types – and understanding these is crucial for diagnosis and appropriate treatment. Here are the most common:
ALZHEIMER’S DISEASE: 60-80 per cent of dementia cases. It is associated with the accumulation of abnormal protein deposits in the brain – amyloid plaques and tau tangles – which interfere with communication between nerve cells.
Early symptoms include progressive memory loss and confusion about time and place.
VASCULAR DEMENTIA: Accounts for around 10-20 per cent of cases and occurs when blood flow to the brain is reduced, often following strokes or damage to small blood vessels, killing brain cells due to lack of oxygen and nutrients. Damage to blood vessels also causes brain stress and inflammation, thought to also trigger abnormal tau build-up.
Symptoms vary, but include problems with planning or problem solving. It can often start abruptly.
LEWY BODY DEMENTIA: Represents 10 per cent of cases and is characterised by protein deposits called Lewy bodies. Symptoms include visual hallucinations, fluctuating cognition and movement problems similarto Parkinson’s.
FRONTOTEMPORAL: This affects 5-10 per cent of dementia patients, typically younger people, often in their 50s and 60s. It impacts on personality, behaviour and language rather than memory initially – as it affects the frontal and temporal lobes of the brain.
MIXED DEMENTIA: At least one in ten people with dementia have more than one type: most commonly, Alzheimer’s and vascular dementia.
These repeated interruptions can also trigger stress responses in the body, leading to increased blood pressure, another dementia risk. A study of 2.3 million people by Birmingham University last year found untreated sleep apnoea was linked to a 12 per cent increased risk for dementia of all types – and a 29 per cent increased vascular dementia risk.
There was no increased risk in people treated with a continuous positive airway pressure (CPAP) machines that keep airways open during sleep.
If your partner regularly complains about your snoring or you often wake feeling tired, ask your GP to refer you to a sleep clinic.
Obesity
Obesity is linked to an up to 30 per cent greater risk of developing dementia in later life, research shows.
‘A “spare tyre” around your middle, particularly in mid-life, is linked to heart disease and the risk of strokes – major dementia risk factors,’ says Professor Livingston.
Abdominal (visceral) fat releases chemicals into the bloodstream that can interrupt normal brain signalling and increase insulin resistance (where the cells stop responding properly to insulin, leading to raised blood sugar levels), and the risk of type 2 diabetes.
It also causes generalised inflammation that may accelerate the accumulation of harmful proteins associated with Alzheimer’s. Even modest weight loss helps. For obese people, losing just 4lb (2kg) could improve cognitive function six months later.
Gum disease
Gum disease contributes to chronic inflammation and infection that can travel via the bloodstream to the brain, says James Goolnik, a dentist at Optimal Dental Health in London. This may lead to brain tissue damage and is linked with the build-up of amyloid proteins – that both raise dementia risk.
A 2021 research review in Evidence Based Dentistry found people with gum disease had 60-80 per cent higher odds of mild cognitive impairment and Alzheimer’s than those with healthy gums and teeth.
Depression
This can double your chances of developing dementia, with the link strongest in mid and later life, research by Nottingham University last year shows.
Seeking treatment may substantially reduce your risk.
A major 2023 study published in the journal Biological Psychiatry, of more than 46,000 UK adults with depression, found those who received treatment – medication or psychotherapy – were a third less likely to develop dementia over a ten-year period than those who didn’t.
It’s thought depression triggers biological changes that harm the brain – including excess cortisol, a stress hormone, that can damage the hippocampus, the memory centre.
It’s also linked with inflammation, possibly reducing the brain’s ability to form new connections between nerve cells.
‘Depression can lead to becoming isolated and lonelier, also associated with greater dementia risk,’ says Professor Malhotra.
Useful checks to help keep it at bay
NHS HEALTH CHECK: Those aged 40-74 in England are eligible for a check-up every five years, to assess the risk of serious conditions such as heart disease (including cholesterol and blood pressure checks) – also linked with higher dementia risk.
CHOLESTEROL: Available through your GP, testing is recommended every five years for those over 40. Anyone with a family history of high cholesterol due to a genetic condition needs annual tests.
BLOOD SUGAR: If at risk of diabetes, your GP can arrange tests. Usually repeated annually for those at increased risk, or every three to six months if diagnosed.
BLOOD PRESSURE: NHS advises monitoring every five years, especially if over 40. If elevated, more frequent tests are recommended. n HEARING: Your GP can refer you for hearing tests at an audiology department. Opticians also offer this free ser vice. Tests are recommended every three years for over-50s, annually if over 60.
EYESIGHT: You qualify for free NHS eye tests every two years if you’re over 60
