New global guidelines highlight exercise, healthy eating, chronic disease management, cleaner air and social connection as key ways to protect brain health throughout life.
For many families, dementia is one of the most feared health conditions of aging.
It can gradually affect memory, thinking, independence and personality, changing not only the life of the person diagnosed but also the lives of spouses, children, caregivers and entire communities.
While researchers continue searching for better treatments, the World Health Organization says one message is becoming increasingly clear: many dementia cases may be linked to risk factors that can be reduced.
According to the WHO’s 2026 Risk Reduction of Cognitive Decline and Dementia: WHO Guidelines, Second Edition, as many as 45% of dementia cases are associated with potentially modifiable risk factors.
Because there is still no widely available cure that can reverse dementia, WHO says prevention and risk reduction remain among the most important tools available.
For California families, the recommendations carry special importance. The state has a rapidly aging population, and many communities continue to face high rates of conditions linked to dementia risk, including diabetes, hypertension, obesity and limited access to preventive care.
The report also emphasizes that protecting brain health is not only an individual responsibility. It is influenced by access to health care, education, neighborhood conditions, air quality and public policy.
Dementia is becoming a major global health challenge
The WHO estimates that 57 million people worldwide were living with dementia in 2021, with the number expected to increase as populations age.
Dementia does not usually appear suddenly. Instead, biological changes can develop over many years, often beginning decades before symptoms become noticeable.
That is why WHO recommends a life-course approach to brain health.
The choices people make in childhood, adulthood and midlife can influence cognitive health later in life. Education, physical activity, nutrition, chronic disease management, social connection and environmental conditions all play a role.
As WHO explains in its report, because there is no widely accessible disease-modifying treatment or cure, reducing risk throughout life remains one of the most effective strategies to lower future dementia rates.
Brain health starts long before old age
A central message in the updated guidelines is that dementia prevention should not begin only when someone reaches retirement age.
Midlife is especially important for managing several risk factors, including:
- High blood pressure
- Diabetes
- Obesity
- Smoking
- Hearing loss
- Physical inactivity
Many of these same conditions also increase the risk of heart disease and stroke.
The connection is important because a healthy brain depends on healthy blood vessels. Protecting cardiovascular health can also support long-term cognitive health.
For families, that means routine medical care, managing chronic conditions and building healthy habits can provide benefits far beyond preventing one disease.
WHO recommendations for reducing dementia risk
The updated guidelines focus on several areas where evidence shows potential benefits.
Regular physical activity
Exercise remains one of WHO’s strongest recommendations.
The organization strongly recommends regular physical activity for adults with normal cognition because research shows it can help reduce cognitive decline.
Physical activity does not require expensive equipment or a gym membership. Walking, cycling, dancing, swimming, gardening and strength exercises can all support healthier aging.
For many families, increasing daily movement may be one of the most practical ways to protect long-term health.
Healthy eating
WHO recommends a balanced diet that provides adequate nutrition and includes a variety of healthy foods.
The organization also warns consumers about relying on supplements marketed as “brain health” products.
Current evidence does not support taking vitamin B, vitamin E, omega-3 supplements or multivitamins solely to prevent dementia in people without deficiencies.
Instead, WHO emphasizes overall dietary patterns rather than individual products or pills.
Managing chronic diseases
The guidelines highlight the importance of controlling conditions that can affect brain health, including:
- Diabetes
- High blood pressure
- Obesity
- High cholesterol
- Hearing loss
Managing these conditions already provides proven health benefits, including reducing risks related to heart disease and stroke.
WHO notes that some dementia-related recommendations are conditional because researchers are still studying the strength of the evidence. However, improving these health conditions remains beneficial for overall well-being.
Staying socially and mentally active
The updated guidelines place greater attention on social connection and cognitive stimulation.
WHO recommends activities such as:
- Reading
- Learning new skills
- Participating in community activities
- Maintaining friendships
- Engaging in mentally stimulating hobbies
Although research on some cognitive activities remains limited, experts believe social and mental engagement may help maintain the brain’s ability to adapt as people age.
For California communities, this highlights the importance of senior centers, libraries, adult education programs and neighborhood organizations that help older adults stay connected.
Cleaner air may also protect brain health
One of the notable additions in the 2026 guidelines is WHO’s recommendation to reduce exposure to air pollution.
The organization recommends reducing exposure to outdoor air pollution, especially fine particulate matter known as PM2.5, and household air pollution. The evidence is still considered limited, but WHO says reducing pollution exposure may help lower dementia risk.
Researchers are studying how air pollution may affect the brain. Possible explanations include chronic inflammation, damage to blood vessels and other biological changes linked to cognitive decline.
The issue is especially relevant in California.
Many communities in Los Angeles County and other parts of the state experience exposure to traffic pollution, industrial emissions and wildfire smoke.
The WHO guidance reinforces that cleaner air is not only an environmental issue but also a public health priority. Improving air quality benefits older adults, children and people living with chronic health conditions.
What WHO does not claim
The guidelines also explain where evidence is not strong enough to make specific recommendations.
WHO does not say that following these steps guarantees someone will avoid dementia.
Instead, the recommendations represent strategies that may reduce risk based on current scientific evidence.
The organization found insufficient evidence to recommend certain interventions specifically for dementia prevention, including some treatments related to sleep problems, depression, hormone therapy, vision treatment and other medical interventions.
These findings do not mean those treatments are ineffective for other health reasons. They mean researchers have not yet proven that they prevent dementia.
Why this matters for California Latino communities
California’s Latino population is aging, making brain health an increasingly important community issue.
Some Latino communities face higher barriers related to preventive health care, chronic disease management and access to healthy environments. Conditions identified by WHO, including diabetes, hypertension and obesity, are already major public health concerns.
Environmental factors also matter. Communities located near highways, industrial areas or areas affected by wildfire smoke may experience greater exposure to pollution that can affect long-term health.
The WHO report emphasizes that dementia prevention cannot depend only on personal choices. Social conditions, neighborhood environments, economic opportunity, education and access to health care all influence people’s ability to reduce risk.
For California leaders and health systems, the message is clear: investing in preventive care, cleaner air, healthy aging programs and community services can help protect both physical and brain health.
For families, the report offers a message of possibility.
No one can eliminate every dementia risk factor. But many everyday actions that support overall health, including staying active, managing chronic conditions, eating well, maintaining relationships and protecting the environment, may also help preserve memory, independence and quality of life as people age.
