Emily Sohn in Nature:
Alzheimer’s disease has long been considered an inevitable consequence of ageing that is exacerbated by a genetic predisposition. Increasingly, however, it is thought to be influenced by modifiable lifestyle behaviours that might enable a person’s risk of developing the condition to be controlled. But even as evidence to support this idea has accumulated over the past decade, the research community has been slow to adopt the idea. This reluctance was obvious as recently as 2010, when the US National Institutes of Health (NIH) brought together a panel of 15 researchers to consider the state of research on preventing Alzheimer’s disease, at a conference in Bethesda, Maryland. Tantalizing findings had begun to emerge that suggested that behavioural choices such as engaging in physical exercise, intellectual stimulation and healthy eating could reduce the risk of brain degeneration. In a 2006 study1 that followed more than 2,200 people in New York for four years, researchers found that people who adhered to a Mediterranean diet — full of whole grains, fruit and vegetables, fish and olive oil — had an up to 40% lower risk of dementia than people who ate more dairy products and meat.
…In 2016, Isaacson’s team observed that after just six months on a personalized preventive plan, participants showed improvements in executive function and mental-processing speed17. The researchers will soon reveal results gathered from a group of more than 150 people at the New York clinic, and the early signs are encouraging. On the basis of this work, Isaacson suspects that 60% of lifestyle recommendations will be the same for everyone; eating a Mediterranean diet, for instance, seems to be a universally positive strategy. The rest should vary from person to person and could include interventions such as aggressive treatment for cardiovascular conditions, medication for sleep apnoea or participation in specific types of physical activity. “We can’t have a one-size-fits-all approach.