A new review published in Ageing Research Reviews synthesizes the evidence linking four modifiable lifestyle factors, nutrition, exercise, gut microbiota, and sleep, to brain health across the lifespan, offering a framework for delaying neurodegenerative disease through daily behavioral choices.
Led by Andrew C. Shin of Texas Tech University, the review draws on original research and landmark studies to examine how diet, physical activity, the gut-brain axis, and sleep interact at the biochemical and physiological level to either accelerate or protect against age-related cognitive decline.
Key points from the review. Brain aging is driven by metabolic and physiological changes that accumulate over decades. The authors argue that lifestyle factors can meaningfully alter this trajectory:
- Nutrition. Specific nutrients, including lipids, glucose, vitamins, and protein, as well as bioactive compounds like flavonoids directly support neuronal health. Macronutrient imbalance, by contrast, contributes to metabolic dysregulation that accelerates brain aging.
- Physical exercise. Exercise drives neuroplasticity through multiple molecular pathways, including brain-derived neurotrophic factor (BDNF), exerkines released during muscle contraction, and endocannabinoid signaling. These mechanisms promote synaptic growth, reduce inflammation, and enhance cognitive reserve.
- Microbiota. The gut-brain axis emerges as a critical mediator. Diet-induced changes in the microbiome can influence neuroinflammation, neurotransmitter production, and blood-brain barrier integrity, all of which affect cognitive resilience.
- Sleep. Sleep is identified as a critical but often underemphasized pillar of brain health. The review incorporates evidence on sleep’s role in glymphatic clearance, synaptic homeostasis, and memory consolidation, linking poor sleep quality directly to accelerated cognitive aging and neurodegenerative risk.
Why it matters. With aging populations worldwide, the burden of neurodegenerative diseases is rising, and pharmacological treatments remain limited. The review’s strength is its integration across domains, rather than treating nutrition, exercise, and sleep as separate interventions, it presents them as interacting systems. For example, exercise improves sleep quality, which in turn enhances glymphatic clearance of metabolic waste; diet shapes the microbiome, which modulates inflammation and sleep regulation. This systems view offers a more realistic basis for public health recommendations than single-factor approaches.
Source. Shin AC, Haque ZF, Galyean S, Hefner M, Esmaeili M, Lawrence JJ, Watkins BA. “Brain Health Across the Lifespan and the Impact of Nutrition, Exercise, Microbiota, and Sleep.” Ageing Research Reviews. 2026 Jul 7:103245. doi:10.1016/j.arr.2026.103245. PMID: 42413699.