Updated: Dec 15, 2020
Miller, A., & Spencer, S. (2014). Obesity and neuroinflammation: A pathway
to cognitive impairment.
Brain, Behavior, and Immunity, 42, 10-21.
Article Review by Kristy Snyder Colling, Ph.D. and Robert Coben, Ph.D.
This article reviews the evidence that obesity and high fat diets cause
inflammation in the brain that adversely affects many crucial functions:
Neuroinflammation affects cognition via inefficient cell signaling.
Inflammation is linked to abnormalities in myelination. Myelin sheaths wrap
around nerve cells and serve as a kind of insulation that facilitates the rapid
transmission of electric signals from cell to cell. When the myelination is
affected, nerve cells cannot communicate efficiently.
Neuroinflammation affects learning and memory. Inflammation alters
synaptic plasticity. Synaptic plasticity is the ability of neurons to form new
connections, which is crucial for learning. Inflammation has also been linked
to reduced hippocampus volume. As hippocampus volume decreases,
memory performance has been shown to decrease as well. Therefore, it
takes longer to learn new information and it is more likely that what is
learned will be forgotten.
Neuroinflammation affects essential regulatory systems. Inflammation is
associated with reduced hypothalamus volume. Reduced volume in the
hypothalamus affects stress management via the regulation of cortisol
levels. Indeed, there is evidence that obese people are more prone to
depression and stress-related mood disorders than their lean counterparts. In
addition, high cortisol levels impair executive functioning, such as impulse
control. When combined with the hypothalamus’ role in regulating hunger,
reduced hypothalamus volume leads to weight gain because people feel
more hungry more often and are less likely to control their impulses to eat
the high fat foods that cause the inflammation that reduces hypothalamus
volume, thus perpetuating the cycle.
While the evidence linking poor diet and obesity to poor brain functioning is
clear, the cycle need not continue to spiral in a negative direction. We at
Integrated Health Coaching located in Fayetteville, Arkansas and as part of our Head On program we can help you turn the process around by helping you to make better food choices and training your brain to better regulate itself and control unhealthy impulses.