By far the most common question I get these days is “do I really need 8 hours of sleep?” With a whimper and a whine, as if I’m asking them to give me their first born child. At the core of this issue is the fact that we don’t feel like we have enough time to get it all done, and so sacrificing precious moments in order to do nothing at all seems like a waste.

Yet, when we start our day with a sleep deficit we trigger our innate stress response, leading us to be vulnerable to even greater distractions and disruptions throughout the day. Sleep is so primal to our ability to recharge our own battery, that anything less than 6 hours has been proven to slow us down and wear us out. We may still trudge through our day and even find success at the end of it, but at what cost? Without adequate energy we rely on stress hormones, caffeine and sugar to give us a temporary boost, but just like running up a steep credit card bill, we’re borrowing energy at a high interest rate.

These internal and external stimulants make us feel jazzed, but inside they trigger inflammation, causing excess wear and tear on our arteries, over stimulating our nervous system, and over time leading to much more serious consequences such as a heart attack, stroke, or brain imbalances like depression and anxiety.

The optimal amount of sleep is unique to each individual. To determine how much sleep you need, you have to find out how much time it takes for you to wake up feeling refreshed without needing an alarm clock. Studies show that humans need 6–10 hours of sleep each night, which is why you’ve most likely heard the recommendation for an average of 8 hours each night.

However, some people can function well with 6 hours of sleep while other people need all 10. According to recent research, dipping below the 6-hour mark impairs cognitive functioning and increases symptoms of stress for just about everyone, so it is recommended that you always get at least 6 hours of quality sleep each night.

If you want to better understand your own sleep style, check out The Power of When by Dr. Michael Breus or watch his segment on our free upcoming Global Stress Summit.

How Do You Know If You’re Not Getting Enough Sleep? If any of the following applies to you, you probably need to get more shut-eye:

1. You’re dependent on an alarm clock. If you’re getting enough sleep, you should be able to wake up on time without a morning alarm.

2. You’re driving drowsy. Falling asleep at the wheel is a sure sign that you are too tired. It’s also incredibly dangerous, as drowsy driving is a common cause of deadly auto accidents.

3. You’re attached to the coffee pot. It’s fine to start with a cup of coffee, but you shouldn’t have to rely on coffee (or other energy drinks) to stay awake throughout the entire day.

4. You make a lot of mistakes. It’s harder to focus and concentrate when you are tired. You’re more easily distracted and less likely to catch and fix errors.

5. You’re forgetful. Sleep loss may explain why you have a hard time remembering things, since sleep deprivation hinders short-term memory.

6. You’re snippy and irritable. Being tired can have a negative effect on your moods. It makes you more likely to feel depressed, anxious, and frustrated.

7. You’re frequently sick. Your immune system is not at full strength without sleep, thereby making it harder for your body to fight illness.

Excerpt from The SHARP Solution, by Heidi Hanna, PhD