By Sarah Brown

"Sleep on it" isn't just good advice for making tough decisions—you can also improve your mental and physical well-being by simply making more time for shut-eye.

"Sleep obviously makes you feel better, but its long-term benefits for your body and mind tend to be taken for granted," says Parinaz Samimi, a sleep and wellness expert at Mattress Firm. "It goes beyond just feeling rested." Plus, if you're trying t lose some weight, sleep and weight loss are connected, so stop sabotaging your efforts.

Here are six common wellness problems you could potentially sleep away tonight:

1. Stress
Daily causes of stress are inevitable, but a good night's sleep can relieve your anxiety and reset your hormones. "Cortisol is a stress hormone, which kicks in when we're in 'fight or flight mode,'" says Anne Danahy, registered dietician and author of Craving Something Healthy. "We need it to survive, but most of us stay in that mode due to everyday stressors. A healthy sleep schedule is the ultimate cortisol regulator."

2. Bad mood
Feeling cranky? There's science for that. Lack of sleep causes the emotional center of the brain, called the amygdala, to become more sensitive, so fatigued people tend to react to situations more negatively. Sleep deprivation causes stress and makes it harder to control your emotions.

3. Lack of focus
"How you think is affected by lack of sleep," Samimi explains. "Your cognition is diminished, as is your attention and decision-making." We've all been there, those mornings where your brain refuses to kick in no matter how much coffee you pour on it. Any work (or play) you think can be accomplished with an all-nighter could be better executed in a well-rested all-dayer.

4. Weight gain
You can't eat when you're asleep, right? There's a bit more to it than that.

5. Illness
Even vitamin junkies and hand sanitizer fanatics can't stave off sickness without at least seven hours of sleep a night. Sleep recharges your immune system and makes it esier to fight off diseases. Also, with insufficient sleep, the human body may react slower to vaccinations.

6. Apprehension
Not so much a health issue as a quality of life issue: "When you're running on low energy levels due to lack of sleep, most any activity seems risky and intimidating," Samimi says. "Well-rested people tend to be more adventurous, more likely to try things out of their comfort zone, in their work and in their daily lives." Maybe a sounder slumber won't turn you into a skydiver, but you might be happier.

If you're not making more time for rest, you could be shortchanging yourself. Better sleep, better health, better you: it's one of the simplest "life hacks" around, and it's totally free!