Eating a healthy diet when young may boost brain health and reduce the risk of cognitive decline later in life, suggests a new study. The research, which tracked diet and cognitive ability over seven decades, found that individuals with healthier diets had better cognitive outcomes over time.
The study involved over 3,000 participants from the UK born in 1946. The findings indicate that maintaining a healthy diet in childhood and midlife is crucial for brain health in old age. Diet plays a significant role in keeping the brain sharp as you age. The earlier you start eating healthily, the better.
This study, presented at NUTRITION 2024, the annual meeting of the American Society for Nutrition, tracked the diet and cognitive abilities of more than 3,000 UK residents. It correlated dietary habits with cognitive ability over seven decades. Those with the highest-quality diets showed better cognitive ability over time compared to peers who ate unhealthy diets.
Cognitive decline can begin at age 65, but brain changes may occur 10 to 15 years before symptoms appear. Consequently, diet much earlier than age 65 might be a crucial factor in later-life cognition. Preliminary findings suggest this could be the case.
The research is based on data from the Medical Research Council’s National Survey of Health and Development, which has collected health and medical information from British citizens for nearly a century. It focused on a specific cohort of 3,059 individuals born in 1946, evenly split between men and women. Those alive today are 78 years old and continue to participate in the study.
Participants reported their dietary information at five points: ages 4, 36, 43, 53, and 63. They also recorded cognitive ability through standard testing seven times between ages 8 and 69. Diet was assessed using the Healthy Eating Index (HEI), factoring in 13 components such as fruits, vegetables, whole grains, and added sugars to create a composite diet score. Assessments used diaries over several days rather than just one day, providing a more detailed picture of diet quality.
Those with healthier diets, particularly at age 43, had better cognitive ability up to age 69. Specifically, 47% of those with the lowest quality diets had the worst cognitive outcomes, while 48% of individuals with the highest quality diets had the best cognitive outcomes. This encompasses general ability across language, memory, reaction time, and visual processing.
Dietary habits may support brain health by reducing oxidative stress and slowing age-related mental decline. “Brain” foods often high in antioxidants and healthy fats include berries, nuts, and fatty fish like salmon, herring, sardines, and walnuts.
Experts recommend focusing on colourful fruits and vegetables (aim for at least six colours daily), a serving of leafy greens each day, and limiting alcohol and ultra-processed foods. If you don’t enjoy fatty fish, consider omega-3 supplementation.
Both experts emphasise the importance of overall diet rather than specific components. Eating healthily over a lifetime is about consistency and finding the right balance that works for you.
The idea is inspiring: knowing that today’s eating habits could impact future cognition might motivate healthier choices.
The study is one of the first to track dietary information and cognitive ability over such a long period. Its findings align with similar studies that highlight the importance of early-life diet on later-life health, particularly cognitive health.
However, it’s essential to consider some limitations of the study. The research relies on self-reported dietary information, which can be subject to recall bias or inaccuracies. Additionally, while the study shows an association between diet quality and cognitive outcomes, it doesn’t establish causality. Other factors such as genetics, lifestyle choices, and socio-economic status might also play significant roles in cognitive health.
Moreover, the findings are still preliminary and not yet published in a peer-reviewed scientific journal. Further research is needed to confirm these results and understand the underlying mechanisms better.
Despite these limitations, the study provides compelling evidence that a healthy diet from an early age could be beneficial for long-term brain health. It underscores the potential impact of dietary choices on cognitive ageing and highlights the need for public health strategies promoting healthy eating from childhood through adulthood.
Maintaining a healthy diet rich in fruits, vegetables, whole grains, and fish like the Mediterranean diet may support brain health and reduce the risk of cognitive decline as we age. While more research is needed to confirm these findings fully, they offer a promising insight into how our dietary habits could shape our cognitive future.
