
Executive summary
The number of older people, including those living with dementia, is rising, as younger age mortality declines. However, the age-specific incidence of dementia has fallen in many countries, probably because of improvements in education, nutrition, health care, and lifestyle changes.

Overall, a growing body of evidence supports the nine potentially modifiable risk factors for dementia modelled by the 2017 Lancet Commission on dementia prevention, intervention, and care: less education, hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, and low social contact.
We now add three more risk factors for dementia with newer, convincing evidence. These factors are excessive alcohol consumption, traumatic brain injury, and air pollution. We have completed new reviews and meta-analyses and incorporated these into an updated 12 risk factor life-course model of dementia prevention. Together the 12 modifiable risk factors account for around 40% of worldwide dementias, which consequently could theoretically be prevented or delayed.
The potential for prevention is high and might be higher in low-income and middle-income countries (LMIC) where more dementias occur. Our new life-course model and evidence synthesis has paramount worldwide policy implications. It is never too early and never too late in the life course for dementia prevention. Early-life (younger than 45 years) risks, such as less education, affect cognitive reserve; midlife (45–65 years), and later-life (older than 65 years) risk factors influence reserve and triggering of neuropathological developments.
Culture, poverty, and inequality are key drivers of the need for change. Individuals who are most deprived need these changes the most and will derive the highest benefit.





“There’s an aging population, and there’s a lot of skin out there,” said Dr. Isaacs. “One in five people in the country develop skin cancer, but there is a plethora of benign skin conditions that also require the expertise of the dermatologist. So, you have increasing demand and a limited supply of dermatologists.”
Health journalist Judy Foreman talks about her new book Exercise Is Medicine: How Physical Activity Boosts Health and Slows Aging
This is Scientific American’s Science Talk, posted on April 24th, 2020. I’m Steve Mirsky. And under our current, often locked-down situation, it’s still really important to try to get some exercise. Judy Foreman is the author of the new book Exercise is Medicine: How Physical Activity Boosts Health and Slows Aging. She’s a former nationally syndicated health columnist for the Boston Globe, LA times, Baltimore Sun and other places, and an author for the Oxford University Press.
Place your hands on the edge of a counter, just beyond shoulder-width apart. Lower into a push-up then press back up. Repeat 10 to 12 times. For more of a challenge, walk your feet farther away from the counter.
“These results are exciting, as they suggest that people may potentially prevent brain shrinking and the effects of aging on the brain simply by becoming more active,” said study author Yian Gu, Ph.D., of Columbia University in New York and a member of the American Academy of Neurology.