Research
Hormonal
Insulin crosses the blood-brain barrier via a saturable transport system, and this transport is impaired in conditions like obesity, diabetes, and aging.
High peripheral insulin levels (common in obesity and diabetes) may not effectively reach the brain due to a saturated transport system. This 'central insulin resistance' can occur even if peripheral insulin is high, potentially contributing to metabolic and cognitive issues.
GoodSupportsHIGH confidence
These results were later confirmed in dogs after the iv administration of insulin... providing the first evidence for a saturable transport system for insulin from blood to the brain... This insulin transport may be regulated by multiple factors... in several pathophysiological situations, such as fasting and re-feeding, obesity, and hibernation, as well as during aging and in patients with diabetes mellitus (DM), and AD.
Why this rating
Supported by multiple experimental studies cited in the review.
Source
Insulin in the Brain: Its Pathophysiological Implications for States Related with Central Insulin Resistance, Type 2 Diabetes and Alzheimer’s Disease
Enrique Blázquez et al. · Frontiers in Endocrinology · 2014
DOI 10.3389/fendo.2014.00161
narrative_reviewCited 478×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Central insulin resistance is a common pathophysiological mechanism linking Type 2 Diabetes and Alzheimer's Disease, contributing to cognitive decline and metabolic dysregulation.Good
- Insulin in the brain acts as an anorexigenic hormone, regulating food intake and energy expenditure through hypothalamic receptors, distinct from its peripheral anabolic effects.Good
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