Beth Ricanati, MD, is a women’s health and wellness physician. You can visit her website for more prescriptions for healthy living.

I thought the pillars of optimal health were threefold: nutrition, exercise and stress management. Now I believe in a fourth – sleep. Enough of it, and especially enough good sleep (deep, restorative REM sleep). Sleep restores our body clock. It restores our energy levels. It even helps us combat chronic disease. I now think of sleep as another essential tool in my arsenal to stay healthy. Current guidelines recommend adults sleep 7-9 hours every night. Many of us (ahem, most of us) don’t meet these recommended guidelines.

Not getting enough sleep interferes with our hormones. Specifically, we have a built-in stress response that releases hormones such as cortisol and epinephrine which are helpful in the moment a stressful event occurs. Known as the “flight or fight” mechanism (the sympathetic nervous system), this stress response has kept us safe for millennia. Today, though, our busy lives – and accompanying lack of sleep – can cause a chronic stress response. In turn, our adrenal glands have to release even more stress hormones. This chronic engagement of our sympathetic nervous system can lead to health problems like rapid heart rate, a rise in blood sugar, and even a rise in blood pressure.

Getting a good night’s sleep can help.

We don’t usually think about sleep until we haven’t had enough of it! How many times have you found yourself just lying there, watching the clock? How many times have you hit the snooze button in the morning? Repeatedly. Fortunately, there’s a lot that goes into a good night’s sleep, even before your head hits the pillow. Good nightly habits can make all the difference. We doctors call it “sleep hygiene,” and it’s way more effective than counting sheep.

Here are some simple steps that I prescribe to my patients and that I try to follow myself:

1| Go to bed at the same time every night and get up at the same time every day.

Go to bed at approximately the same time every night, within a half hour, and you’ll start to train your mind and body that this is bedtime. And yes, getting up at the same time is tough. Of course some people like to sleep in on weekends and/ or vacation, but those extra hours don’t make up for the lost sleep. There are no sleep banks to store the hours!

2| The bed is just for sex and sleeping.

Forget reading the next great American novel. Forget watching TV with a bowl of popcorn. Forget checking your phone. Your bed is just for sex and sleep. You want to break any other behavioral associations and reinforce this simple rule. The light from your devices’ screens blocks the production of melatonin, a brain chemical that’s crucial for falling asleep. Keep your devices out of the bedroom at night! Use curtains and/ or shades to keep the room dark. Keep the temperature on the cooler side.

3| Foods can help you sleep (but some can actually lead to worse sleep).

Avoid caffeine after mid-afternoon since it is a stimulant and can keep youp. Alcohol near bedtime – although it initially acts as a sedative – is a known sleep-disrupter. How many of you have woken up at 3am after a few glasses of wine? Instead of alcohol, try a calming cup of hot tea or warm organic milk (grass-fed if possible). Dairy-free? Try turkey, nuts, seeds, oats, chicken and organic tofu. All these foods are high in the amino acid tryptophan, which is used to make melatonin, a hormone that regulates our sleep-wake cycles. Other melatonin-supporting foods to try include cherries (eat one cup before bed), bananas and oranges.