Scientists say vitamin may support brain health in older adults

Scientists are examining a familiar nutrient for a new role. Vitamin C, long known for immune support, may also help preserve brain structure in older adults, according to a study published in PLOS One. Researchers analyzed blood samples and MRI scans from 2,044 older adults. They found those with higher vitamin C levels had greater gray matter volume and stronger connectivity in the brain’s default mode network. The link held even after factoring in age, sex, and lifestyle habits like smoking or alcohol use. The study adds to a growing body of research exploring how dietary nutrients influence brain health, highlighting the potential for nutritional interventions to complement traditional approaches to cognitive aging. Alexander Y. Zubkov, a neurologist and integrative medicine advisor, and Amy Davis, a dietitian, both contributed insights to the findings, emphasizing the intersection of diet and neuroscience in this context.

Gray matter is essential for cognitive functions such as memory and decision-making. Alexander Y. Zubkov, a board-certified integrative neurologist and physician advisor for 1MD Nutrition, explains that gray matter volume—adjusted for head size—is a sign of brain resilience. The study suggests the nutrient may be one of several factors that support long-term brain health. Gray matter, composed of neuronal cell bodies and synapses, is critical for processing information and executing complex tasks. Its decline is associated with not only neurodegenerative diseases but also with reduced cognitive flexibility and slower reaction times. Zubkov notes that maintaining gray matter volume may delay the onset of these conditions, though the study does not establish causality, only a correlation.

The default mode network plays a role in memory and emotional regulation. Amy Davis, a dietitian and founder of The Balanced Dietitian, notes that higher vitamin C levels correlate with stronger connections in this network. However, the study only shows an association, not proof that the nutrient causes these benefits. Zubkov emphasizes that the nutrient acts as a key antioxidant in the brain, neutralizing harmful byproducts from brain activity. It also helps produce neurotransmitters and maintain cell membranes. The default mode network, active during rest and introspection, is involved in self-referential thinking, memory consolidation, and emotional processing. Disruptions in this network have been linked to mood disorders and cognitive decline, making its preservation a key target for brain-protective strategies.

The brain retains the nutrient at higher concentrations than the bloodstream, Zubkov adds. This suggests the nutrient is vital for brain function. Previous studies on vitamin C supplements for brain health have shown mixed results, he says. A diet rich in natural sources appears more effective. Davis recommends foods like oranges, guava, bell peppers, strawberries, and leafy greens. The brain’s ability to concentrate vitamin C—reaching levels up to 10 times higher than in the blood—indicates its specialized metabolic needs. This concentration may support the brain’s high energy demands and protect against oxidative stress, which is a major contributor to neuronal damage. However, the efficacy of supplements remains uncertain, as dietary sources provide a broader array of nutrients and phytochemicals that may synergistically enhance brain health.