UNDATED – Daylight Saving Time returns at 2 a-m tomorrow.

That means you should set your clocks forward one hour before going to bed tonight.

If you haven’t already been preparing for the change by going to bed earlier than usual, you’ll probably feel some effects from the change as your body attempts to adjust.

That’s because you’ll be dealing with an hour of lost sleep and your circadian rhythm – or internal clock – gets out of whack...which can leave you feeling a bit off.

That can actually trigger mental illness, including bipolar disorder and seasonal affective disorder.

One study in Denmark found an 11% increase in depression cases after the time change.

Other studies linked an increase in heart attacks when DST begins.

There’s been an increase in the number of state legislatures considering staying on daylight saving time year round or eliminating it altogether. Those efforts have mostly failed, but they reveal a trend towards acknowledging the health impacts, death toll and economic ramifications without any major saving benefits of DST.