New Delhi: If you want to remember what you ate for breakfast at 80, now is the time to pay attention to what you ate at 40.A large study published in JAMA Neurology tracking more than 1.5 million adults found that a healthy diet in midlife is linked to better memory and thinking ability later on. Those who ate more fruits, vegetables, whole grains and fish were less likely to report early symptoms of cognitive decline and performed better on cognitive tests over time.

The findings shed light on an important but often overlooked window of age, ages 45 to 54, when long-term brain health appears to take shape.Monita Gehlot, dietician, AIIMS Delhi, said this happens when multiple risk factors like high blood pressure, blood sugar imbalance, inflammation and vascular damage start silently and gradually affecting the brain. “Middle life is an important window because the brain still retains enough flexibility for lifestyle changes, especially diet, to have a meaningful impact. Habits formed during this stage help build cognitive reserve and may prevent or reduce the risk of dementia,” he said.Among the diets studied, the DASH (Dietary Approaches to Stop Hypertension) diet showed one of the strongest associations with a reduced risk of cognitive decline, reinforcing its benefits beyond heart health. Ritika Samaddar, chief clinical nutritionist, Max Super Specialty Hospital, said diet plays a direct and continuing role in brain health in adulthood. “A plant-based diet rich in fruits, vegetables, whole grains, nuts, seeds and healthy fats like olive oil and fish is key. Also, intake of red and processed meat, refined carbs, sugary drinks and ultra-processed foods should be reduced,” she said.He said diet affects the brain in many ways. “A healthy gut microbiome supports cognition and mood, while a poor diet increases inflammation and oxidative stress, which leads to damage to brain cells. Stable blood sugar and good vascular health are equally important for maintaining brain function,” he said.Studies have linked diets high in red and processed meat and diets associated with inflammation or increased blood sugar to worse brain outcomes.Experts say brain aging begins very early, and prevention should begin in mid-life. In a country like India, where dementia cases are expected to rise rapidly, the findings reinforce the importance of prevention.