Allostatic load and disordered white matter microstructure in overweight adults

Area of Science:

• Neuroscience
• Physiology
• Public Health

Background:

• Overweight and stress are associated with brain structural abnormalities.
• The allostatic load model links homeostasis disruption to oxidative stress, inflammation, and potential brain damage.
• The impact of allostatic load on the central nervous system is not fully understood.

Purpose of the Study:

• To investigate the relationship between allostatic load and white matter tract composition in overweight individuals.
• To examine grey matter changes associated with increased allostatic load.

Main Methods:

• Comparative study involving 31 overweight-to-obese adults and 21 lean controls.
• Assessment of allostatic load indexes.
• Magnetic resonance imaging (MRI) to evaluate white matter (fractional anisotropy) and grey matter composition.

Main Results:

• Overweight participants had significantly higher allostatic load indexes.
• Increased allostatic load correlated with reduced fractional anisotropy in specific white matter tracts (inferior fronto-occipital fasciculi, right anterior corona radiata).
• Higher allostatic load was associated with grey matter reductions in key brain regions (left precentral gyrus, left lateral occipital gyrus, right pars opercularis).

Conclusions:

• Overweight status, even without other apparent health issues, is linked to detrimental long-term biological changes in the brain.
• Allostatic load may serve as a biomarker for neurobiological alterations in overweight individuals.
• Findings highlight the potential neuroprotective benefits of weight management.