Intermittent Fasting Probably Works by Changing Your Microbiome

Intermittent fasting mouse

Intermittent fasting is the latest greatest biohack to lose weight and improve health. It’s all the rage in Silicon Valley.


There’s plenty of research on the subject, but it’s somewhat controversial and the mechanisms behind any health benefits are not fully understood.


Now a study in the journal Cell Metabolism shows that in mice, intermittent fasting promotes white adipose browning and weight loss by altering the gut microbiome.


The basics:

Brown fat (Brown Adipose Tissue) is a type of fat that acts a bit like muscle. When stimulated in a cold environment this fat burns calories to produce heat.


White fat is the stuff that sits under the skin and gives you a belly – the “inch that you pinch.”


Beige fat is a mixture of brown and white fat. Activating brown fat to produce energy using white fat is a promising strategy for the treatment of obesity.


What did the study show?

In the study, the researchers found that every-other-day fasting stimulates beige fat, effectively reducing obesity and insulin resistance (a huge problem that causes diabetes).


When they studied the gut microbiomes of the fasting mice, the researchers found that the composition of the bacteria shifted to degrade acetate (thus producing butyrate and propionate short chain fatty acids) and lactate and to activate beige fat cells.


Basically, fasting told the gut bacteria in the mice to make signals that activate brown fat.


It will be interesting to see if these findings can be replicated in humans, as the metabolism of mice is quite different to humans.