Visceral Fat Correlates With Brain Tissue Damage
Building and maintaining excess fat tissue, specifically the visceral fat clustered around internal organs, harms long-term health in numerous ways. It raises the risk of suffering from all of the most common age-related medical conditions, and raises lifetime medical expenditures even while lowering life expectancy. A primary mechanism here is thought to be greater levels of chronic inflammation spurred by this fat tissue, but visceral fat is metabolically active and prompts a wide range of changes throughout an individual's body. One of the end results is a greater level of physical damage to brain tissue over time, largely a result of breakage and failure in tiny blood vessels:
Obesity has been associated with microstructural brain tissue damage. Different fat compartments demonstrate different metabolic and endocrine behaviors. The aim was to investigate the individual associations between abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) and microstructural integrity in the brain. This study comprised 243 subjects aged 65.4 ± 6.7 years. The associations between abdominal VAT and SAT, assessed by CT, and magnetization transfer imaging markers of brain microstructure for gray and white matter were analyzed and adjusted for confounding factors.Our data indicate that increasing visceral adipose tissue rather than subcutaneous adipose tissue is associated with microstructural brain tissue damage in elderly individuals. This association cannot be accounted for by BMI, which is an easily obtainable clinical measure of obesity but does not discriminate different fat compartments. Awareness of differences in the underlying mechanisms between body fat patterns and brain damage may offer more focused individual advice or treatment than considering BMI only. Further research in a general population with a wider age range is necessary to study whether the relationship between visceral adiposity and microstructural brain tissue damage is merely a result of ageing, or exists independently of age. Furthermore, cognition tests could be of additional value for evaluating the clinical consequences of these findings.
Link: http://onlinelibrary.wiley.com/enhanced/doi/10.1002/oby.21048/
These studies all seem quite shaky now that that huge higher BMI <=> lower dementia study came out earlier this year. http://www.thelancet.com/journals/landia/article/PIIS2213-8587%2815%2900033-9/fulltext
Yes, they are measuring visceral vs subcutaneous, and not BMI, but it doesn't sound very plausible for BMI > 35 people to have lower amounts of fat anywhere than BMI 22 people.