017 Sneaky Reasons You're Always Tired (And What to Do About Them)

Not enough sleep is the obvious culprit when you're dragging through the day. But what about when you're getting a reasonable number of hours and still waking up exhausted?

Daytime tiredness has a surprising number of causes — and most of them are fixable once you know what you're dealing with. Here are seven overlooked sources of fatigue that sleep researchers and health experts point to most often.

031. Blue Light Is Suppressing Your Melatonin

Your phone, laptop, and tablet emit blue-wavelength light that signals your brain to stay awake. At night, this directly suppresses melatonin — the hormone that tells your body it's time to sleep.

The fix isn't complicated: stop using screens 1–2 hours before bed. If that's not realistic, at minimum:

  • Enable Night Shift on iOS or Android's night mode to shift screen color temperature toward warmer tones
  • Try f.lux on your computer for automatic color adjustment after sunset
  • Blue-light-blocking glasses (amber or orange lenses) can reduce melatonin disruption when worn in the evening

Blue light itself isn't inherently bad — it's useful during the day to keep you alert. The problem is exposure after dark, when your body is trying to wind down.

042. You're Not Eating Enough Before Bed

Eating too little — especially too few carbohydrates — can cause blood sugar to drop in the middle of the night. When that happens, your body releases cortisol and adrenaline to compensate. Those stress hormones can pull you out of sleep or prevent you from sleeping deeply in the first place.

This doesn't mean eating a big dinner late at night. It means making sure you've had enough to eat overall, and having a small, balanced snack in the evening if needed. Good options before bed: a small amount of complex carbs with some fat or protein — think whole grain toast with nut butter, or a handful of nuts and a piece of fruit.

053. You're Missing Key Sleep-Supporting Nutrients

Certain foods contain compounds that naturally support your body's ability to fall and stay asleep. Worth knowing:

  • Tryptophan — a precursor to serotonin and melatonin. Found in turkey, dairy products, almonds, and pumpkin seeds.
  • Magnesium — a natural muscle relaxant that supports nervous system calm. Found in whole grains, eggs, dairy, and dark leafy greens.
  • Natural melatonin — yes, it occurs in food. Oats, tart cherries, and oatmeal all contain it.
  • Glucose from honey — honey contains glucose that may help signal the brain to reduce orexin, a chemical that promotes wakefulness.

You don't need to overhaul your diet. But if you're chronically tired, it's worth asking whether your eating habits are giving your body what it needs to sleep well.

064. Stress, Anxiety, or Depression Is Disrupting Your Sleep Architecture

Mental health and sleep are tightly intertwined — and it goes in both directions. Poor sleep worsens anxiety and depression; anxiety and depression disrupt sleep.

Stress keeps the nervous system activated, which works against the physiological slowdown (lower heart rate, reduced metabolism, slower breathing) that your body needs to fall asleep. Chronic stress can keep cortisol elevated at night, resulting in lighter, more fragmented sleep even when you're technically getting enough hours.

If sleep problems are tied to anxiety, depression, or ongoing stress, treating the underlying issue matters more than optimizing your sleep environment. Talk to your healthcare provider — effective options exist, and they work.

075. What You Do After Waking Up at Night Makes Things Worse

Most people wake up 4–6 times per night at the end of natural sleep cycles. That's normal. The problem comes from what happens next.

Lying still and trying to "relax" your way back to sleep tends to backfire. Instead, your mind typically starts running through the day's worries, and the awakening drags on. According to sleep medicine experts, a better strategy is to pick up a book or put on an audio book. The mental engagement distracts your brain, allows drowsiness to return naturally, and shortens the time you spend awake.

Avoid checking your phone — the light and content will make it harder, not easier, to fall back asleep.

086. You May Have Undiagnosed Sleep Apnea

Sleep apnea causes repeated breathing interruptions during sleep, dropping blood oxygen levels and fragmenting sleep without the person being fully aware of it. The result is chronic fatigue even after what feels like a full night of sleep.

Common signs include:

  • Loud snoring
  • Waking with a dry mouth or headache
  • Waking up to urinate more than once
  • Being told you gasp or stop breathing during sleep
  • Persistent daytime sleepiness regardless of hours slept

Sleep apnea is underdiagnosed — an estimated 80% of moderate to severe cases go undetected. If you check several of these boxes, talk to your doctor. Home sleep tests are now widely available and don't require an overnight clinic stay.

097. Caffeine, Sugar, and Refined Carb Crashes Are Draining You

Caffeine has a longer half-life than most people realize — it can stay in your system for 5 to 7 hours, disrupting sleep quality even when you're not aware of it. Regularly relying on coffee to function is a sign the underlying sleep issue isn't being addressed.

Sugar and high-glycemic carbs cause rapid blood glucose spikes followed by crashes. That mid-afternoon slump — the lethargy, irritability, and brain fog — is often reactive hypoglycemia: your blood sugar rising fast and then dropping sharply. The fix is straightforward: pair carbs with protein and fat to slow absorption and prevent sharp swings.

A few practical rules:

  • Cut caffeine by 2 pm (or earlier if you're sensitive)
  • Avoid meals that are carbs-only — always include fat or protein
  • Limit added sugar; save sweets for early in the day, not before bed

10The Mattress Connection

It's also worth noting that poor sleep quality is sometimes about the surface you're sleeping on. An unsupportive or worn-out mattress can cause pressure points, heat buildup, and restless nights that leave you tired regardless of how many hours you log.

If you've addressed the factors above and you're still waking up unrefreshed, it may be worth evaluating your mattress. Visit any of our LA Mattress Store locations and test a few options — we offer a 120-night comfort guarantee so you can be confident you've found the right fit.

11Frequently Asked Questions

Why am I always tired even after 8 hours of sleep?

Several things can cause this: poor sleep quality (fragmented sleep cycles), sleep apnea, stress, blood sugar issues, or a sleep environment that prevents deep rest. If it's chronic, worth discussing with a doctor.

Does blue light really affect sleep?

Yes. Blue-wavelength light suppresses melatonin production, which delays sleep onset and reduces sleep quality. The effect is strongest in the 1–2 hours before your normal bedtime.

Can what I eat affect how tired I am during the day?

Significantly. Blood sugar instability, nutrient deficiencies (especially magnesium), and undereating can all contribute to daytime fatigue and disrupted sleep. Diet is an often-overlooked sleep variable.

What's the best way to fall back asleep after waking at night?

Read a physical book or listen to an audio book rather than lying awake or reaching for your phone. Mental distraction helps drowsiness return naturally and shortens middle-of-the-night wake periods.

How do I know if I have sleep apnea?

Common signs include snoring, gasping during sleep, morning headaches, dry mouth, frequent nighttime urination, and persistent tiredness despite enough sleep. A home sleep test can confirm or rule it out — ask your doctor.