As a sleep physician with over a decade of experience, I frequently hear patients say they fall asleep just fine, but wake up at 3 a.m. and can't get back to sleep.

If this resonates with you, your body might be waving a red flag. Waking up in the middle of the night a couple of times a week for over three months isn't just a bad season. 

It may indicate chronic insomnia, a long-term sleep disorder where a person has trouble falling asleep, staying asleep, or waking too early — at least three times a week for three months or more. Chronic insomnia is often treated with a combination of cognitive behavioral therapy and professional medical intervention. 

Here are some of the most common causes of insomnia, and how to address it: 

1. Alcohol wrecks your sleep

Alcohol is the No. 1 sleep disruptor. Even a single glass can interfere with brain waves and suppress REM sleep. 

REM, or rapid eye movement, is the sleep stage when we dream and the brain processes emotions and memories. As alcohol metabolizes, typically over four to five hours, your brain experiences a rebound effect, leading to fragmented, restless sleep in the latter half of the night. 

Moreover, it takes about 25 hours for alcohol to fully clear from your system, meaning you are still suffering from the consequences the day after.

If you choose to drink alcohol, do it at least three hours before sleeping. Or why not enjoy it at a brunch?

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2. Your room feels like a tropical beach

Your body thrives in a cool, dark and quiet cave to sleep in. The sweet spot is between 60 to 67 degrees Fahrenheit.

Invest in air conditioning, cooling mattress toppers and breathable bedding made from natural fibers like cotton or bamboo.

3. Heavy meals lead to heavy sleep problems

Consuming heavy meals late at night can force your digestive system to work overtime.

Additionally, nighttime metabolism slows, making it harder for your body to manage large meals and blood sugar fluctuations — both potential sleep disruptors.

Give your body a break and opt for lighter evening meals. Aim to finish eating a few hours before bedtime.

4. Your nighttime anxiety is working overtime

Waking up at 3 a.m. and ruminating over past events is often a sign of stress misfiring. This isn't productive reflection, but rather intrusive thoughts disrupting your rest.

Try to incorporate pre-bedtime journaling, deep breathing exercises or progressive relaxation techniques into your routine. 

If these unwinding strategies prove ineffective, consider consulting a therapist to help you identify dysfunctional beliefs that you might not be aware of.

5. That afternoon coffee is sneakier than you think

Just because you fall asleep without issue doesn't mean caffeine is done with you. Caffeine can also affect the quality of your sleep and prevent you from fully entering into a deep, restorative rest. 

Cut caffeine intake at least eight hours before bedtime, which, for most individuals, means no later than 2 to 3 p.m.

And remember, if you only give your body five to six hours, you never even hit the good stuff — the restorative deep and REM cycles that come later. Seven to nine hours puts you in full repair mode.

6. Snoring and sleep apnea are keeping you up

Loud snoring, waking up gasping or experiencing dry mouth upon waking may indicate sleep apnea, a condition characterized by interrupted breathing during sleep. Sleep apnea not only breaks your sleep into pieces but also increases the risk of heart disease, diabetes and depression. 

It often worsens in the latter half of the night, around 3 a.m. If this rings true for you, I recommend using the STOP-Bang questionnaire, a screening tool to help evaluate your risk for obstructive sleep apnea. 

If results indicate a high risk, get checked — your partner (and your heart) will thank you.

7. Use supplements wisely (they're not magic)

Certain supplements may support sleep, especially when you have foundational habits in place:

• L-theanine: Can calm the mind; pairs well with magnesium.
• Glycine: Can lower body temperature, promoting longer sleep.
• Valerian: May assist during menopause, but can cause grogginess and vivid dreams.

However, it is important to consult your physician before taking any supplements. Remember, supplements are sidekicks, not a replacement for healthy sleep habits.

Ultimately, achieving quality sleep isn't solely about falling asleep quickly. If you're consistently waking at 3 a.m., it's essential to heed your body's signals. 

Rather than relying on quick fixes, address the root causes. Chronic insomnia is treatable with appropriate interventions. My best advice is to seek professional guidance rather than unproven remedies.

Dr. Samanta Dall'Agnese is a Sleep physician and Ear, Nose, and Throat specialist with over 12 years of medical experience. She trained at the world's largest sleep laboratory and is certified by the World Association of Sleep Medicine. Beyond clinical care, she has worked with digital health startups to expand access to sleep solutions. Dr. Dall'Agnese is also an active voice on social media, where she shares practical, science-backed advice about sleep and the basic human senses. She is the founder of Sleep Skool, a global community for people who want better sleep and better health.

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