The World Health Organization (WHO) released updated guidelines and evidence-based recommendations to help people reduce their risk of cognitive decline and dementia.
The guidelines apply to adults with normal cognition or mild cognitive impairment. They are intended primarily for healthcare providers, though they may help policymakers to support population-level interventions, the WHO said.
More than 57 million people have dementia worldwide and nearly 10 million people are diagnosed every year. Alzheimer’s disease is the most common form of dementia and is estimated to account for 60% to 70% of cases. In the U.S., the number of people with Alzheimer’s disease exceeds 7 million.
Up to 45% of dementia risks can be attributed to modifiable risk factors like smoking, alcohol use, social isolation, physical inactivity, air pollution, or diseases like hypertension and diabetes, according to the WHO report.
“We know more today than ever before about what drives dementia risk, and these guidelines translate that knowledge into action,” WHO Director-General Tedros Adhanom Ghebreyesus, PhD, said in a statement.
The document updates previous WHO guidance from 2019. They recommend behaviors and interventions like cognitive training, cognitive stimulation, and engagement in social activities. They include interventions to increase physical activity, stop tobacco use, reduce alcohol consumption, and adopt a healthy diet. They also feature new recommendations to reduce air pollution exposure, to consider dietary restriction interventions for adults with overweight or obesity, and to offer tailored multidomain interventions when needed.
Managing cardiometabolic conditions like hypertension, diabetes, and high cholesterol can help reduce dementia risk, the guidance said. Hearing aids may be part of risk-reduction strategies for some people.
The updated advice does not recommend vitamins B and E, omega-3 polyunsaturated fatty acid, or multivitamin-mineral supplements to reduce risks of cognitive decline or dementia in the absence of a diagnosed deficiency, based on moderate-certainty evidence, the WHO said.
Menopausal hormone therapy also is not recommended for specifically reducing the risks of cognitive decline or dementia in postmenopausal women ages 65 and older, based on very low-certainty evidence. For women under age 65, there was not enough evidence to make a determination, the group pointed out.
There also was not enough evidence to make recommendations about whether improving sleep or managing depression would influence cognitive decline or dementia risk, the WHO said.
Many risks addressed in the WHO guidelines overlap with those found in the 2024 report of the Lancet Commission on dementia prevention, intervention, and care, which showed that about 45% of dementia cases were potentially preventable by addressing 14 modifiable risk factors at different stages of life.
“The illness which is usually most feared by people is dementia,” said Lancet Commission leader Gill Livingston, MD, of University College London.
“Health professionals are in the position to understand and communicate risk factors which each individual has and can change. This gives people choice and empowers them,” Livingston told MedPage Today.
“Tackling risk such as physical inactivity or hearing loss improves quality of life immediately,” she observed.
“In the longer term, some people will avoid dementia because of this knowledge; others will live longer in health and less long with dementia,” Livingston added. “Some will still develop dementia but later. They must be offered care and support.”
