Healthy childhood diet keeps dementia away, scientists say

A healthy diet from childhood up until the middle age can keep the brain functioning well into the senior years, cutting off the risk of dementia, according to a new large-scale study.

The yet-to-be peer-reviewed research, whose findings were presented at the Nutrition 2024 conference, assessed data from over 3,000 participants who were followed from their childhood for nearly seven decades.

While until now studies on dementia have focused on the eating habits of people in their 60s and 70s, the latest research is the first to track diet and cognitive ability throughout people’s lifespan, say scientists from Tufts University.

People’s cognitive abilities are known to improve up until middle age and may start declining after 65.

However, the new findings suggest following a healthy diet rich in plant-based foods with high levels of antioxidants and mono- and polyunsaturated fats from early life onwards can support brain health by reducing stress within cells and improving blood flow to the brain.

This includes a diet high in whole or less-processed plant foods such as leafy green vegetables, beans, whole fruits and whole grains.

“These initial findings generally support current public health guidance that it is important to establish healthy dietary patterns early in life in order to support and maintain health throughout life,” study co-author Kelly Cara said.

“Our findings also provide new evidence suggesting that improvements to dietary patterns up to midlife may influence cognitive performance and help mitigate, or lessen, cognitive decline in later years,” she said.

In the research, scientists analysed data from 3,059 UK adults enrolled as children in a study called National Survey of Health and Development.

The participants provided crucial health data on their dietary intakes, cognitive performance, and other information via questionnaires and tests conducted for about 75 years.

Scientists found that dietary quality was closely linked with trends in cognitive ability.

Citing an example, they said only about 8 per cent of the participants with low-quality diets had what they labelled “high cognitive ability” and about 7 per cent of people with high-quality diets had “low cognitive ability” compared with their peers.

For instance, participants in the “highest cognitive group” had much higher memory retention and information processing speed compared to those in the “lowest cognitive group”, the study noted.

Nearly one in four participants in the “lowest cognitive group” showed signs of dementia at this timepoint, while none in the “highest cognitive group” showed signs of dementia.

Even slight differences in diet quality in childhood appeared to set the tone for later life diet – for better or worse – scientists say.

They suspect that the cumulative effects of diet over time could be linked to how cognitive abilities fare over time.

However, since the participants were mostly white, researchers say further studies are needed to determine whether these results apply to more diverse populations.