As global populations age, the prevalence of neurodegenerative diseases, particularly Alzheimer’s disease (AD), is rising dramatically. AD, the most common form of dementia, accounts for 65.23% of cases among the 15.07 million elderly affected in China alone. Emerging research highlights the critical role of nutrition—especially vitamins and minerals—in preventing cognitive decline. Recent studies reveal that daily supplementation with folate, B vitamins, vitamin D (VD), and coenzyme Q10 (CoQ10) can significantly slow cognitive deterioration in older adults. Additionally, magnesium (Mg) intake is linked to improved brain health, reducing dementia risk. This article explores the science behind these nutrients and their potential to safeguard cognitive function.
The Escalating Crisis of Alzheimer's Disease in Aging Societies
The Three Stages of AD: A Gradual Neurodegenerative Process
Subjective Cognitive Decline (SCD): The initial phase is marked by subtle, self-reported memory lapses. Individuals may struggle with encoding new information—such as forgetting names or misplacing objects—while objective tests show no deficits. This "silent phase" often goes unrecognized, yet it represents a critical window for intervention.
Mild Cognitive Impairment (MCI): Here, cognitive deficits become detectable via neuropsychological assessments. Memory problems worsen, and individuals may exhibit difficulties with language, attention, or decision-making. MCI is the earliest stage where AD can be clinically diagnosed, though not all cases progress to AD.
Clinical Alzheimer's Disease: The final stage is characterized by severe cognitive and functional decline, including memory loss, disorientation, language breakdown, and loss of daily living skills. By this point, neuronal damage is extensive, and current treatments can only modestly alleviate symptoms, not reverse the disease.
The Imperative for Early Prevention: Why Nutrition Matters

doi: 10.3390/nu15051243
Key Findings by Nutrient
- Folic Acid (Vitamin B9):
Cognitively normal individuals who took daily folic acid supplements reduced their risk of developing cognitive impairment by 43.0% compared to non-users. Folate is critical for DNA synthesis and methylation, processes linked to neuronal development and synaptic plasticity. - B Vitamins (Complex of B1, B2, B3, B6, B12, etc.):
Even occasional B vitamin use lowered cognitive decline risk by 36.1%, while daily intake produced a 60.9% risk reduction. B12 and B6, in particular, are involved in homocysteine metabolism; high homocysteine levels are associated with neuroinflammation and amyloid deposition. - Coenzyme Q10 (CoQ10):
Daily CoQ10 supplementation conferred a 40.6% reduction in cognitive decline risk. As a mitochondrial antioxidant, CoQ10 supports energy production in neurons, which are highly metabolically active and vulnerable to oxidative stress. - Vitamin D (VD):
Normal individuals saw a 46.8% risk reduction with daily VD. Uniquely, VD also slowed disease progression in those with MCI: daily or occasional use reduced the risk of MCI advancing to AD by 60.5% and 42.8%, respectively.
Multivariate analysis results
Mechanistic Insights into Vitamin Action
VD's active form, 1,25(OH)₂D, acts as a steroid hormone, binding to nuclear receptors in neurons. It regulates calcium homeostasis (critical for synaptic transmission), promotes neurotrophin synthesis (e.g., BDNF), and suppresses microglial inflammation. Recent studies suggest VD may reduce amyloid-beta (Aβ) accumulation by enhancing Aβ clearance via the blood-brain barrier.
Prospective analyses link B vitamin sufficiency to "cognitive reserve"—the brain's ability to withstand pathological damage. This may involve epigenetic mechanisms: folate and B12 influence methylation of genes like NUDT15(involved in oxidative stress response) and;TXNRD1;(regulating redox balance), reducing neuronal damage from free radicals.
Magnesium: The Underestimated Mineral for Brain Health
https://doi.org/10.1007/s00394-023-03123-x
The Magnesium-Brain Health Link
Association between dietary Mg intake and brain volume
Mechanisms of Magnesium's Neuroprotection
Dietary Sources and Practical Recommendations
Magnesium-Rich Foods