In men, higher body fat is linked to increased activity in the nerves that control blood vessel constriction and heart rate, but this link is observed in Caucasian men and not in Pima Indian men,...
Mechanism
Synthesis from 1 study
More body fat usually makes the nervous system more active, but in some people, the signal from fat to the nervous system gets weakened because the body stops responding well to insulin. This means that even with lots of fat, the nerves don’t turn up — and this happens more often in certain groups...
Most probable mechanism
When a person has more body fat, their body becomes less responsive to insulin, which normally helps increase nerve activity that controls blood flow and metabolism. In some people, this reduced response means that even with high fat levels, the nerves don’t become more active at rest. In others, the nerves still become more active with more fat, likely because their insulin signaling still works well enough to drive that response.
Increased adipose tissue mass leads to chronic elevation of circulating insulin due to insulin resistance in metabolic tissues
Insulin normally acts on central neural circuits to increase sympathetic outflow to skeletal muscle
In individuals with higher adiposity, insulin’s ability to stimulate sympathetic outflow is reduced due to impaired signaling in hypothalamic or brainstem pathways
This blunted sympathetic response to insulin results in a dissociation between adiposity and resting muscle sympathetic nerve activity in certain populations
Evidence from Studies
Supporting (1)
Community contributions welcome
Muscle Sympathetic Nerve Activity in Response to Glucose Ingestion: Impact of Plasma Insulin and Body Fat
Contradicting (0)
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