The World Health Organization has issued a major update to its guidance on reducing the risk of cognitive decline and dementia. The second edition revises the original 2019 report to reflect more recent evidence and advances in dementia risk reduction.

Seven additional health conditions and exposures have been added to the guidance. They involve menopausal hormone therapy, cardiovascular health, traumatic brain injury, vision impairment, sleep, infections such as HIV, and exposure to toxins and air pollution.

Dr. Daniel Amen, a physician and founder of Amen Clinics in California, discussed the additions with Fox News Digital. His own approach to reducing Alzheimer’s risk factors uses the acronym BRIGHT MINDS.

The acronym represents blood flow, retirement and aging, inflammation, genetics, head trauma, toxins, mental health, immunity and infections, neurohormones, diabesity and sleep. Diabesity refers to the co occurrence of obesity and type 2 diabetes, and the WHO guidance offers similar advice.

Here's What They're Not Telling You About Your Retirement

Menopausal hormone therapy is primarily used to treat menopause symptoms. The WHO does not recommend it specifically to prevent dementia in postmenopausal women who are 65 and older, while it says evidence is insufficient to determine whether it affects dementia risk in younger women.

Amen agreed that there is not enough evidence to support using menopausal hormone therapy specifically for dementia prevention. He said hormonal changes during menopause may affect mood and memory, although the connection between the therapy and dementia risk remains uncertain.

"For women, as they go through menopause, lower progesterone makes them anxious, and [with] lower estrogen, they start to have memory problems," Amen said. "Hormone replacement early on is helpful, and that's what we see on the brain imaging work that we do."

Experts note that cognitive and mood symptoms associated with hormonal changes during menopause can vary widely. Meanwhile, conditions affecting the heart and blood vessels can also affect brain health and are associated with a higher risk of dementia, according to Amen.

This Could Be the Most Important Video Gun Owners Watch All Year

Those conditions can include heart disease, heart rhythm problems, stroke and transient ischemic attacks. A stroke occurs when blood flow to part of the brain is blocked or when a blood vessel in or near the brain bursts, according to the American Stroke Association.

Erectile dysfunction can also be associated with underlying vascular disease, Amen said. He also argued that the WHO is "late to the party" in emphasizing head trauma as a dementia risk factor.

Traumatic brain injury can range from a mild concussion to a severe brain injury. Amen said his brain imaging work has shown serious consequences for some people with mild traumatic brain injuries, including temper problems, depression and anxiety.

Vision is another area addressed in the updated guidance because a significant portion of the brain is dedicated to sight, according to Amen. "So, if your vision becomes troubled, your brain's troubled," he said.

Amen said vision impairment may create additional demands on the brain. However, although vision impairment has been linked with cognitive decline, the WHO says evidence is insufficient to recommend vision treatment specifically to prevent dementia.

Sleep is also highlighted, and sleep challenges affect tens of millions of Americans. In 2024, 30.5% of United States adults reported getting less than seven hours of sleep each day, according to the CDC.

Amen said sleep problems such as sleep apnea can cause brain changes that resemble hallmarks of Alzheimer’s disease. Research suggests sleep may help the brain clear beta amyloid, although the relationship between sleep and dementia remains complex and is still being studied.

Inflammation and infections can affect brain health as well. Untreated HIV can affect the central nervous system and is associated with HIV related cognitive impairment, while effective antiretroviral therapy has greatly reduced the incidence of severe HIV associated dementia.

Amen said he has scanned "hundreds of people" with HIV and described the virus as "clearly a risk factor." Exposure to substances and pollutants, including alcohol, marijuana, lead, mercury and air pollution, could also be detrimental to brain health, according to Amen.

The WHO recommends reducing exposure to household and outdoor air pollution, particularly fine particulate matter. Research has linked long term exposure to air pollution with a higher risk of cognitive decline and dementia, although the organization characterizes the evidence as having low to very low certainty.

Dementia risk rises sharply with age, and a recent United States analysis estimated that about one in five people had developed dementia by age 85. Amen said prevention efforts should begin well before older age and include social activity, new learning, stronger connections with others and better decisions.

---

Are you feeling overwhelmed or hopeless right now? Have you been withdrawing from people or activities you usually enjoy? Are you having thoughts about hurting yourself, or feeling like things will never improve?

You do not have to handle those feelings alone. Support is available, and talking to someone can make a difference. You can reach out to the 988 Suicide & Crisis Lifeline by calling or texting 988, or by chatting online at 988lifeline.org. Trained counselors are available 24 hours a day to listen and help.

If you believe someone is in immediate danger, call emergency services right away. Even a small step, like reaching out to a trusted friend, family member, or professional, can help create a path forward.