Something I hear often from many of my shift working clients is “ever since starting shift work, I’ve continued to gain weight.”
Perhaps this is something that you can relate too as well.
But why is this so?
Well the etiology (or cause) of weight gain and/or obesity is certainly very multifactorial, but one of the biggest drivers behind weight gain is due to a satiety or ‘hunger hormone’ called leptin. You may remember from a previous blog post – Weight Loss and Shift Work, where I discuss how sleep deprivation is actually a type of endocrine or hormone disruptor – one of which includes leptin.
Leptin is a hormone that is stored in our fat cells and essentially tells us when we are feeling full. It does this by sending a message to the pituitary gland in our brain, telling us when we’ve had enough to eat, and that we do not require any more food.
Quite simply, it acts a bit like a petrol gauge in our car, telling us when we’re full, versus getting close to empty.
But what happens in leptin resistance?
Well when we put on more and more weight, we produce more and more leptin which causes the receptors of our cells (the part of the cell which receives stimuli) to become fatigued (or resistant). In other words, the body fails to receive those “I’m feeling full” signals, subsequently tricking the body into believing it isn’t carrying enough weight and needs to eat more.
It’s kind of a Catch 22 really, because the more fat we have, the more leptin is produced.
See the dilema here?
So if you keep putting on more and more weight, then you gain more and more fat cells which triggers more and more leptin, which causes the body to wrongly tell you that you’re starving, when in fact, you’ve probably had more than enough to eat.
It really can become a vicious cycle, but what can you do about it?