Treating common diseases that do not directly affect the brain such as gum disease and diabetes could slash dementia cases by around a third, new research suggests.
Chinese researchers have linked dementia risk to 16 peripheral diseases including gum, liver and heart disease, type 2 diabetes, osteoarthritis, inflammatory bowel disease, arthritis and a group of lung conditions known as COPD.
These join hearing and vision loss, which have long been known to increase the risk of Alzheimer's disease, the most common type of the memory-robbing condition.
'Our study revealed that maintaining peripheral organ health may be an important component of global policies for brain health promotion and dementia prevention.'
In the study, published in Nature Human Behaviour, the researchers analysed data from over 200 earlier research studies to estimate the risk of 26 different diseases.
They found that 16 of these were associated with an increased risk of developing dementia, corresponding to 18.8million cases globally.
Of these gum disease, chronic liver disease, hearing and vision loss, and type 2 diabetes were found to carry the highest risk.
Whilst the researchers findings do no yet demonstrate a causality between the diseases, they some cases could be prevented by treating other related diseases early.
Millions of dementia cases could be prevented by treating other non-brain related health conditions experts say
In a major new consensus, published last month, world-leading experts said millions of dementia cases could be prevented through simple lifestyle changes as they unveiled a 'roadmap' to beat the disease.
They set out 56 evidence-based recommendations, building on 14 existing risk factors put forward by the 2024 Lancet Commission including tackling hearing loss, improving public health messaging and securing sustained funding for prevention.
But the researchers of the current study say simply identifying the risk factors is not enough.
'Amid the rapidly increasing burden of dementia, promoting brain health has become a global priority.
'However merely identifying these risk factors is not sufficient.
'Given the close interconnection between the brain and peripheral health, preserving peripheral organ health may be crucial for brain health.
'As most peripheral diseases are preventable, addressing them may offer a strategy that not only directly benefits peripheral organ health but also supports brain health, thereby contributing to overall human well-being.'
They added that putting more effort into strategies that prioritise the management of these conditions could alleviate the increasing burden of dementia and help prevent millions of cases worldwide.
For instance, they urged health officials to consider implementing oral health education and regular dental appointments for people at a high risk of gum disease - such as those over 50, diabetics and smokers.
It is currently estimated that over half of British adults either have gum disease or are at risk of developing it. Around 90 per cent of people over 50 are susceptible to the early stages of the disease.
But once identified, gum disease is easily treated - a move which experts say could also slash the risk of diabetes, heart disease and dementia.
When it comes to liver disease prevention, the authors recommend the expansion of the hepatitis B vaccine, as outlined in the World Health Organization's (WHO) goal to eliminate hepatitis as a public health threat by 2030.
There should also be greater efforts to inform the public about the health risks of drinking alcohol - which can severely impact the liver's ability to filter out toxins from the blood and fight infection and disease.
They concluded: 'These interventions are feasible by building on established programmes, cost effective through low-cost vaccines preventing expensive-to-treat diseases and early education, reducing long term costs and scalable via existing systems such as schools or clinics for rapid high-risk area rollout.
'Moreover, public health policies should adopt a more proactive approach to mitigate disease with rapidly increasing trends, particularly diabetes, in order to address emerging health challenges effectively and with foresight.'
The study builds on findings from the 2024 Lancet Commission, which concluded that almost half of all Alzheimer's cases could be prevented.
These include high cholesterol, untreated hearing and vision loss, physical inactivity, social isolation and long-term exposure to air pollution - factors the authors say are still not being tackled seriously enough at a population level.
Around 900,000 people are currently living with dementia in the UK, a figure expected to rise to more than 1.6million by 2040. Dementia is the leading cause of death, accounting for more than 74,000 deaths a year.
The number of people with dementia globally is expected to nearly triple to 153million by 2050 with the health and social costs already costing in excess of £780bn a year.
At the same time, dementia receives far less research funding than other major illnesses such as cancer, despite costing the UK economy an estimated £42billion a year.
Charities have also warned progress could stall further after dementia was removed from official NHS planning guidance this year, effectively signalling it should be de-prioritised.
Yesterday, it was revealed that more than one in three cancers could be prevented with simple lifestyle changes.
In one of the first studies of its kind, researchers analysed 19 million cases of 36 different cancer types in nearly 200 countries, including the UK and US.
Using 2022 figures, the latest available, the team found 38 percent, or 7.1 million diagnoses, were attributable to 30 modifiable risk factors.
Despite consistent declines in smoking rates across the world, tobacco smoking was the leading modifiable risk factor for cancer, accounting for one in six cases. It was also the top preventable risk factor in men.
Infections, including the sexually transmitted infection human papillomavirus (HPV), a leading cause of cervical and anal cancer, which can be prevented with vaccination and safe sex practices, were linked to one in ten cancer cases and were the top causes for women, while alcohol was responsible for three percent.