Hi and

every week I'm your host Dr. Ellen Hendrickson

and every week I'll help you meet life's challenges with evidence-based research, a sympathetic

ear, and zero judgment.

Why are Americans so tired?

Well, aside from hoping sleep can be replaced by a non-fat double latte, there are lots of sneaky culprits that steal our shut-eye.

We covered seven surprising reasons in the episode, Why Am I So Tired tired but they don't stop there. Here are four more things

that may be sabotaging your sleep. Reason number one, sleeping in.

What? Well, it's counterintuitive, but true.

Sleeping in can actually make you feel more tired.

Why?

Well, the answer lies in your circadian rhythms. If you have a job with set hours, you probably

wake up at the same time every day during the week. On the weekends, though, you may relish the chance

to get a few more hours of shuti. However, from plants to animals

to bacteria, all living things follow a built-in daily rhythm and your body is no different.

Its circadian rhythms follow a 24-hour cycle

so your body temperature, metabolism, and levels of hormones like cortisol and

melatonin, ebb and flow.

And these rhythms are controlled internally by groups of cells in your hypothermalmus,

but they also take cues from the external environment, especially daylight.

So by sleeping in on Saturday morning, you inadvertently throw off your rhythms, which makes you

feel jet-lagged, groggy, unable to concentrate, not to mention grumpy, and we won't even get into the GI symptoms, but suffice

...