Bad night's sleep? A new study published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism (JCEM) found that two 30-minute cat naps could help make up for a lack of sleep the night before.

Researchers observed 11 healthy young men between the ages of 25 and 32 in a laboratory setting. During a one-night session the men were only allowed to sleep for two hours. Then they took two 30-minute restorative naps, one at 9:30 a.m. and the other at 3:30 p.m.

When hormone levels were tested in the subjects’ urine and saliva, the men who experienced insufficient sleep had a 2.5-fold increase in their norepinephrine levels, a stress hormone that is involved in the body’s flight-or-fight response. However, after taking a 30-minute nap in the morning and the afternoon, there was no increase in the hormone. Additionally, interleukin-6, a protein with antiviral properties connected to immune function, dropped after too little sleep, and then normalized after napping. The results suggest napping can help with better immune function and stress reduction.

Dr. Brice Faraut of the Université Paris Descartes-Sorbonne Paris Cité said about the findings, “This is the first study that found napping could restore biomarkers of neuroendocrine and immune health to normal levels. Napping may offer a way to counter the damaging effects of sleep restriction by helping the immune and neuroendocrine systems to recover. The findings support the development of practical strategies for addressing chronically sleep-deprived populations, such as night and shift workers.”

A lack of sleep has been linked to many health problems. Harvard notes on its website that consistently getting too little sleep has been tied to obesity, cardiovascular disease, type-2 diabetes, hypertension, mood disorders, weakened immune function and even lower life expectancy.

And yet people still aren’t getting enough hours of sleep. A 2013 Gallup poll found that 40 percent of Americans get less than the recommended number of hours of sleep per night. People under the age of 50 were the most likely to believe they weren’t sleeping enough.

How much sleep do you need?

The National Sleep Foundation recently revised its sleep recommendations:

  • Newborns (0-3 months): 14-17 hours each day
  • Infants (4-11 months): 12-15 hours
  • Toddlers (1-2 years): 11-14 hours
  • Preschoolers (3-5): 10-13 hours
  • School age children (6-13): 9-11 hours
  • Teenagers (14-17): 8-10 hours
  • Younger adults (18-25): 7-9 hours
  • Adults (26-64): 7-9 hours
  • Older adults (65+): 7-8 hours
The National Heart, Lung and Blood Institute (NIH) notes that while napping can help in the short-term to boost alertness and performance, it cannot make up for lost sleep in the long term. NIH explains, “If you routinely lose sleep or choose to sleep less than needed, the sleep loss adds up. The total sleep lost is called your sleep debt. For example, if you lose 2 hours of sleep each night, you'll have a sleep debt of 14 hours after a week.”

The researchers who conducted the napping study didn’t look at the power of naps when subjected to regular sleep deprivation, so based on other research and recommendations, it’s probably best to get a good night’s sleep as regularly as possible, and know that, in a pinch, napping may you feel better.

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