Sleep and the Immune System

Sleep and the Immune System

If you’re always sick, your sleep patterns may be to blame. Multiple studies confirm a reciprocal link between sleep and the immune system: Sleep loss impacts the immune response, and the immune system, in turn, alters sleep patterns.

How Does Sleep Affect the Immune System?

The body’s immune response is regulated by cytokines, which act as signaling molecules in immune system and the brain. Like most biological systems, the immune system has a circadian rhythm. T-cells and levels of pro-inflammatory cytokines are highest at night, while leukocytes and the anti-inflammatory cytokine IL-10 rise during daytime.

During illness, increased levels of pro-inflammatory cytokines correspond with increased fatigue, which make you feel more tired. This natural response to the onset of an illness encourages you to sleep more, which helps you recover from illness. Cytokines also increase and fragment deep, NREM sleep and decrease REM sleep, which can help explain why you may sleep restlessly during illness.

These natural cycles are disrupted in people with certain chronic conditions. For people with chronic inflammation or autoimmune diseases, such as fibromyalgia or chronic fatigue syndrome, high levels of inflammation result in constant fatigue that’s not related to an acute illness. For many, this chronic fatigue is debilitating.

Chronic sleep loss decreases the body’s production of protective cytokines, lowering the body’s response to infection and increasing our vulnerability to disease.

Sleep and Stay Well

One of the best ways to stay healthy is to simply get adequate sleep on a regular basis. Practice good sleep hygiene to support healthy sleep and a strong immune system:

  • Maintain a consistent sleep and wake schedule.
  • Avoid alcohol in the last hour before bed.
  • Avoid stimulants like caffeine up to 8 hours before bed.
  • Don’t use screens for an hour or two before sleep.

Learn more about cytokines and their impact on sleep patterns here.

Additional Resources