Infographic: A Body Without Food

Mounting evidence suggests that intermittent fasting causes significant changes to various organs and tissue types.

Bob Grant
Bob Grant

Bob started with The Scientist as a staff writer in 2007. Before joining the team, he worked as a reporter at Audubon and earned a master’s degree in science journalism...

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May 31, 2017

© AMPON AKEARUNRUNG/SHUTTERSTOCK.COM

The fasting signal likely starts in the liver, the body’s central command for metabolism. But through changes in gene expression and alterations in complex enzymatic pathways, the effects of food deprivation spread throughout the body, from the brain and visceral fat to the muscles and more.

LIVER
Fasting and time-restricted feeding increases insulin sensitivity, decreases insulin resistance, and lowers blood glucose levels. With prolonged periods of fasting, the liver’s glycogen stores become depleted, and visceral fat is tapped as an energy source, which releases ketones that can be metabolized by neurons and muscle cells.
 
IMMUNE SYSTEM
Periodic fasting reprograms T-cell populations, tamping down autoimmunity and rescuing immunosenescence. A lack of incoming calories appears to prune away autoimmune T cells, and with refeeding, hematopoietic stem cells are activated to replace T cells, lymphocytes, and other white blood cells. Several fasting studies have also pointed to a...

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